Transmission Swap Review - LS versus SIR with LS 5th
01-06-2011, 07:16 PM
#1
Transmission Swap Review - LS versus SIR with LS 5th
Hey everyone, members, enthusiasts, and guests reading this, recently I've gotten some goodies installed on my teg. I went from the factory LS transmission to a (Canadian) Civic SIR transmission built up with new bearings, seals, and an LS 5th gear. After some fun, I wanted to share my thoughts on the idea of a transmission swap onto the Integra's B18b1. Please keep in mind the motor is not built internally, and has nothing but a short-ram AEM intake.
Please note: A summary of my findings is below for those of you who don't want to read the whole review.
The LS Transmission
Also known by its S80 code, the LS transmission is the longest and most economical of the b-series family.(See http://www.superhonda.com/forum/f5/b...-codes-218900/ for gear ratios and specifics). You have to have a lot more ponies on tap than the factory B18b provides to be able to really capitalize on the longer time spent in the engine's powerband. This is one of the reasons many consider this to be a good choice for a build within the realm of forced induction.
If you're only running stock internals, like I am, and not about to start building the motor, you may be looking for a way to go faster without necessarily making more power. Probably the easiest way to do that is to free up the ponies you already have, by way of more effective gearing and reducing rotating mass (and can't forget about reducing weight altogether)
The SIR Transmission
I don't have a transmission code reference, as this is a bit of a frankenstein transmission I'm running. It was originally the gearset, ring gear, and differential out of one transmission, installed into a different transmission's hydro housing. What is important to remember though, is that the setup is as follows:
-Gearset from SIR transmission, 1st through 4th
-Ring gear from SIR transmission
-5th gear from an LS transmission
Also installed while I was doing the swap was an Exedy Stage 1 clutch (as a result of the unfortunate failure of the release bearing with the previous clutch) as well as a Type R flywheel to reduce rotating mass a bit without going overboard, since it's all apart anyway. GM Syncromesh was used in the fluid department.
Initial Impressions
I was excited to see what a difference this transmission would make in acceleration, and did my 1000k break-in of the clutch, shifting at no more than 3k. The clutch was significantly stiffer, due to the thicker pressure plate, but felt like there was a more positive feel and it grabbed more agressively throughout. I noticed this immediately even in the low RPM's during the break-in period. Impressed already.
I could feel that acceleration was easier and with less bogging than the previous transmission, as well as a noticeable difference in the way RPM's climbed and also dropped between shifts. Mind you, I was in 5th gear by the time I hit 60 km/h - having to shift under 3,000 RPM's. The lighter flywheel was only slightly noticeable in time up/down in RPM, but the difference in responsiveness was profound. I felt on the highway the speed was scrubbed off a little faster as well once you let off the gas and let it coast in gear. Altogether, the engine felt noticeably more responsive, but I decided I will be able to truly tell once I let the engine's RPM's really climb.
Post Break-In
I was getting anxious to give 'er, but am a firm believer in sticking to the break-in schedule in order to make sure things go smoothly and parts wear in the way they're intended to. Hot spots are not a good thing.
I started off going to 5,000 RPM's and playing around there, and does it get there quickly! Shifts were seamless and crisp due to the new clutch, however I noticed it is very important to literally follow the layout of the markings on the shift ****, or even exaggerate the motion (as in the case between 2nd and 3rd), otherwise you risk grinding gears (it did happen a couple times while I got the hang of it). I can't stress this enough, a precise shift from 2nd to 3rd is very important, there's no such thing as a straight motion from 2nd to 3rd like you see many Honda drivers do. The close ratio of the gearbox and the tight nature of the transmission means precision is key.
Climbing higher closer to redline, the transmission/flywheel combo really shines. Acceleration is effortless, and power delivery is as smooth as I've ever seen it. I am blown away by how profound the difference is in both power delivery as well as the actual pull you feel versus the old transmission.
The LS 5th
This is probably the section most of you are interested in, so I'll make it as informative as I can. First and foremost, 5th gear on the highway with the B18 and stock sized tires sits you at 4,000 RPM @ 120 km/h. It is important to remember that the ring gear is still out of the short box so you are at a higher RPM, HOWEVER - lower still than you would have with a full B16/SIR gearset (by up to 750 RPM, which is the approximation based on my research both on paper and on the street in other cars)
Power, you ask? YES! Many of you know the LS transmission for being terrible on the highway because of the lack of power. Fuel efficient as it gets, but you step on it and you wait an eternity to get anywhere. This is not the case anymore, as you're litereally a couple hundred revs out of the engine's powerband and the needle climbs quite quickly once you jam the pedal to the floor.
Speaking of fuel efficiency, I remember with my winters I've gotten 475km/tank consistently with the LS transmission, driving as I do now (which I would estimate is 50% highway, 30% city, and 20% givin' her the beans
) With this transmission and the same winter tires, I get 425km/tank. The 50km range drop is about a 10% change. Not bad considering you have power all the time.
Word of warning though, this is the kind of situation where your engine's drone due to the exhaust will be most heard and possibly most annoying, so keep it in mind.
All in all, B18b's are not known to handle high RPM's for as long as their vtec counterparts (on stock internals, anyway), so staying lower is a good way to go for long-term reliability. That said, I do recommend the LS 5th - The part's about $125 brand new from Honda. I couldn't imagine being consistently at almost 5,000 RPM on the highway with this motor, that would be nuts. One may choose to stay away from super short (full) gearsets on non-vtec motors from this reason.
The bottom line? Short 1st-4th and Long 5th is THE way to go for a good compromise between fuel efficiency while still making power and tire squealing fun in the lower gears.
The Summary
The Setup
-Gearset from SIR transmission, 1st through 4th
-Ring gear from SIR transmission
-5th gear from an LS transmission
The Clutch
-Exedy Stage 1
Pros
-Power delivery and smoothness through powerband
-Shorter gearbox means quicker acceleration
-LS 5th makes the most of any fuel efficiency to be gained while still keeping the ring gear of the short box
-A great alternative for those looking to accelerate faster without building the motor to make more horsepower
Cons
-Expensive labour for the swap
-Fuel efficiency lost, to a degree
-If you cannot be precise with your shifts, you'll grind gears and complain (namely between 2nd to 3rd)
-Higher highway cruising RPM can get annoying if your car is normally loud
Some numbers
-4,000 RPM @ 120km/h on stock size tires
-50km drop in distance covered with a full tank of 87 versus a full LS transmission.
Conclusions
If you can afford it, by all means. If you have a transmission swap lined up, now's the time to do it. If you have a transmission rebuild coming up, even better.
Labour is expensive to tear apart the transmission and install an LS 5th in an existing gearset, however if the job's already being done, the money you save in forgone gas consumption that you would OTHERWISE (without the swap) spend makes it worth it.
It puts a smile on my face, every gear, every time
-David
Please note: A summary of my findings is below for those of you who don't want to read the whole review.
The LS Transmission
Also known by its S80 code, the LS transmission is the longest and most economical of the b-series family.(See http://www.superhonda.com/forum/f5/b...-codes-218900/ for gear ratios and specifics). You have to have a lot more ponies on tap than the factory B18b provides to be able to really capitalize on the longer time spent in the engine's powerband. This is one of the reasons many consider this to be a good choice for a build within the realm of forced induction.
If you're only running stock internals, like I am, and not about to start building the motor, you may be looking for a way to go faster without necessarily making more power. Probably the easiest way to do that is to free up the ponies you already have, by way of more effective gearing and reducing rotating mass (and can't forget about reducing weight altogether)
The SIR Transmission
I don't have a transmission code reference, as this is a bit of a frankenstein transmission I'm running. It was originally the gearset, ring gear, and differential out of one transmission, installed into a different transmission's hydro housing. What is important to remember though, is that the setup is as follows:
-Gearset from SIR transmission, 1st through 4th
-Ring gear from SIR transmission
-5th gear from an LS transmission
Also installed while I was doing the swap was an Exedy Stage 1 clutch (as a result of the unfortunate failure of the release bearing with the previous clutch) as well as a Type R flywheel to reduce rotating mass a bit without going overboard, since it's all apart anyway. GM Syncromesh was used in the fluid department.
Initial Impressions
I was excited to see what a difference this transmission would make in acceleration, and did my 1000k break-in of the clutch, shifting at no more than 3k. The clutch was significantly stiffer, due to the thicker pressure plate, but felt like there was a more positive feel and it grabbed more agressively throughout. I noticed this immediately even in the low RPM's during the break-in period. Impressed already.
I could feel that acceleration was easier and with less bogging than the previous transmission, as well as a noticeable difference in the way RPM's climbed and also dropped between shifts. Mind you, I was in 5th gear by the time I hit 60 km/h - having to shift under 3,000 RPM's. The lighter flywheel was only slightly noticeable in time up/down in RPM, but the difference in responsiveness was profound. I felt on the highway the speed was scrubbed off a little faster as well once you let off the gas and let it coast in gear. Altogether, the engine felt noticeably more responsive, but I decided I will be able to truly tell once I let the engine's RPM's really climb.
Post Break-In
I was getting anxious to give 'er, but am a firm believer in sticking to the break-in schedule in order to make sure things go smoothly and parts wear in the way they're intended to. Hot spots are not a good thing.
I started off going to 5,000 RPM's and playing around there, and does it get there quickly! Shifts were seamless and crisp due to the new clutch, however I noticed it is very important to literally follow the layout of the markings on the shift ****, or even exaggerate the motion (as in the case between 2nd and 3rd), otherwise you risk grinding gears (it did happen a couple times while I got the hang of it). I can't stress this enough, a precise shift from 2nd to 3rd is very important, there's no such thing as a straight motion from 2nd to 3rd like you see many Honda drivers do. The close ratio of the gearbox and the tight nature of the transmission means precision is key.
Climbing higher closer to redline, the transmission/flywheel combo really shines. Acceleration is effortless, and power delivery is as smooth as I've ever seen it. I am blown away by how profound the difference is in both power delivery as well as the actual pull you feel versus the old transmission.
The LS 5th
This is probably the section most of you are interested in, so I'll make it as informative as I can. First and foremost, 5th gear on the highway with the B18 and stock sized tires sits you at 4,000 RPM @ 120 km/h. It is important to remember that the ring gear is still out of the short box so you are at a higher RPM, HOWEVER - lower still than you would have with a full B16/SIR gearset (by up to 750 RPM, which is the approximation based on my research both on paper and on the street in other cars)
Power, you ask? YES! Many of you know the LS transmission for being terrible on the highway because of the lack of power. Fuel efficient as it gets, but you step on it and you wait an eternity to get anywhere. This is not the case anymore, as you're litereally a couple hundred revs out of the engine's powerband and the needle climbs quite quickly once you jam the pedal to the floor.
Speaking of fuel efficiency, I remember with my winters I've gotten 475km/tank consistently with the LS transmission, driving as I do now (which I would estimate is 50% highway, 30% city, and 20% givin' her the beans
) With this transmission and the same winter tires, I get 425km/tank. The 50km range drop is about a 10% change. Not bad considering you have power all the time. Word of warning though, this is the kind of situation where your engine's drone due to the exhaust will be most heard and possibly most annoying, so keep it in mind.
All in all, B18b's are not known to handle high RPM's for as long as their vtec counterparts (on stock internals, anyway), so staying lower is a good way to go for long-term reliability. That said, I do recommend the LS 5th - The part's about $125 brand new from Honda. I couldn't imagine being consistently at almost 5,000 RPM on the highway with this motor, that would be nuts. One may choose to stay away from super short (full) gearsets on non-vtec motors from this reason.
The bottom line? Short 1st-4th and Long 5th is THE way to go for a good compromise between fuel efficiency while still making power and tire squealing fun in the lower gears.
The Summary
The Setup
-Gearset from SIR transmission, 1st through 4th
-Ring gear from SIR transmission
-5th gear from an LS transmission
The Clutch
-Exedy Stage 1
Pros
-Power delivery and smoothness through powerband
-Shorter gearbox means quicker acceleration
-LS 5th makes the most of any fuel efficiency to be gained while still keeping the ring gear of the short box
-A great alternative for those looking to accelerate faster without building the motor to make more horsepower
Cons
-Expensive labour for the swap
-Fuel efficiency lost, to a degree
-If you cannot be precise with your shifts, you'll grind gears and complain (namely between 2nd to 3rd)
-Higher highway cruising RPM can get annoying if your car is normally loud
Some numbers
-4,000 RPM @ 120km/h on stock size tires
-50km drop in distance covered with a full tank of 87 versus a full LS transmission.
Conclusions
If you can afford it, by all means. If you have a transmission swap lined up, now's the time to do it. If you have a transmission rebuild coming up, even better.
Labour is expensive to tear apart the transmission and install an LS 5th in an existing gearset, however if the job's already being done, the money you save in forgone gas consumption that you would OTHERWISE (without the swap) spend makes it worth it.
It puts a smile on my face, every gear, every time
-David
01-06-2011, 08:15 PM
#2
Congrats Dave, read the whole review and you did it spot on and covered everything. Glad your enjoying the new transmission. Always wondered how this transmission works well now I know.
Sticky anyone!!!
Sticky anyone!!!
01-08-2011, 11:21 AM
#7
Only thing i dont get is...what is the whole 2-3 gear shift about? did you use brand new synchros? because regardless of the transmission or gear ratios, it should and IS capable of lining up for next gear immediately with a straight across jab. Since once you pass the neutral and go into the grove for 3rd the shifter assembly inside the transmission is set up for 3rd gear regardless if you go across from 2nd to 3rd or go to neutral over and then 3rd. My old b16, never had any problems with any gears, and by no means have i cared about the trans at all.
01-08-2011, 11:34 AM
#8
nice write up bro.
Ive been in the car with david and seen how he has to "baby" the tranny so it wont grind. I had a VERY slight grind at 6000rpm. I through some GM syncro mesh into it... and BOOM grind fixed.
Ive been in the car with david and seen how he has to "baby" the tranny so it wont grind. I had a VERY slight grind at 6000rpm. I through some GM syncro mesh into it... and BOOM grind fixed.
01-08-2011, 02:40 PM
#9
I did not use new syncros, they were merely wire wheeled and cleaned up.
For whatever reason, every B16 transmission in my friends circle has had the same personality. Just likes a slower shift - trying to be precise ensures a seamless shift every time, that's all.
I find grinding has a lot more to do with how you shift than any specific mechanical issue. I'm a firm believer in proper shifting technique and swear by its importance.
It's more of a "personality" than an issue, because it's only a slight driving style adjustment and you've got no grinding and tons of fun, so a non-issue as far as I'm concerned.
Cheers
For whatever reason, every B16 transmission in my friends circle has had the same personality. Just likes a slower shift - trying to be precise ensures a seamless shift every time, that's all.
I find grinding has a lot more to do with how you shift than any specific mechanical issue. I'm a firm believer in proper shifting technique and swear by its importance.
It's more of a "personality" than an issue, because it's only a slight driving style adjustment and you've got no grinding and tons of fun, so a non-issue as far as I'm concerned.
Cheers
01-08-2011, 04:32 PM
#11
I'm interested to hear your take on it, bring it up next time we meet and we'll discuss. I'm not sure whats causing it, but this is the way I found the transmission likes to be driven.
There's not much I can do now but review it as I experience and enjoy it the way it is
There's not much I can do now but review it as I experience and enjoy it the way it is
01-08-2011, 05:03 PM
#14
Junior Member
Join Date: May 2010
Location: toronto
Posts: 383
lol id like a spot in the presentation that martin is going to present.
maybe we should have a little debate on this subject?
or a throw down. ls integra with frankenstein tranny vs b20 hatchback with b16 tranny. lol
maybe we should have a little debate on this subject?
or a throw down. ls integra with frankenstein tranny vs b20 hatchback with b16 tranny. lol
01-11-2011, 07:33 AM
#17
LS for the longer gears is typically better for turbo'd cars. Shorter gear ratios are king for N/A setups
01-11-2011, 08:51 AM
#18
Moderator
Join Date: May 2010
Location: Where my car is.
Posts: 724
Bought my car with 90k 5 years ago and it now has 260k. It's a b16 (SiR) transmission.
2nd to 3rd gear shifts have always needed to be a delicate and precise execution. Get it right and I can shift 2-3 as fast and smooth and any gear change. When I'm slightly off, I get a bit of a crunch or it doesn't go in at all and sounds like gravel in a food blender!
It's always been that way.
And yeah, for turbo applications, use an LS trans.
I like this write-up, Dave. Very interesting and informative. I often wish the SiR trans had a 6th gear or that 5th was taller. Never thought of combining the b16's 1-4 with 5th from an LS... Cool stuff.
2nd to 3rd gear shifts have always needed to be a delicate and precise execution. Get it right and I can shift 2-3 as fast and smooth and any gear change. When I'm slightly off, I get a bit of a crunch or it doesn't go in at all and sounds like gravel in a food blender!
It's always been that way.
And yeah, for turbo applications, use an LS trans.
I like this write-up, Dave. Very interesting and informative. I often wish the SiR trans had a 6th gear or that 5th was taller. Never thought of combining the b16's 1-4 with 5th from an LS... Cool stuff.
01-16-2011, 09:52 AM
#19
2nd to 3rd gear shifts have always needed to be a delicate and precise execution. Get it right and I can shift 2-3 as fast and smooth and any gear change. When I'm slightly off, I get a bit of a crunch or it doesn't go in at all and sounds like gravel in a food blender!
It's always been that way.
It's always been that way.
UPDATE : I have about 3000 km on the setup now, still working fantastic. It's getting easier and easier to make seamless shifts at any temperature and RPM.
The higher RPM exhaust drone is starting to annoy me here and there. Summer exhaust project is in the works.
Man, it's great fun.
02-03-2011, 02:30 PM
#20
n00b
Join Date: Jun 2010
Location: Bowmanville
Posts: 45
Hey, if I can ask;
WHO did the work for you for this tranny?
I swapped out my LS tranny for a B16 when I swapped in my b20vtec. In the city, especially going down a good hill from a stop, I freaking LOVE this tranny!!! LOVE IT!!! Nothing like rowing through those gears quickly and listening to the engine and feeling the response. LOVE IT!!!
BUT, I HATE it on the highway. HATE IT!!!! I FREAKING HATE IT! Do you how many times I've unconsciously reached down and shifted OUT of 5th looking for that MISSING 6th gear. I drive 90kms one way each day to work on the 401 and I keep worrying that 1 day my engine is just gonna blow up running at a sustained 5000 rpm for so long.
Though I DO still love having the responsiveness when passing without having to gear down, but I'd happily sacrafice that since I usually gear down anyway to pass - JUST CUZ I CAN! lol I love BLOWING by someone rather than just passing. Yeah, that was me! lol
Recently I've heard of the LS 5th gear and I've been given this a lot of thought. A LOT.
I went from over 500kms (close to 600kms with my LS and b18b1) a tank down to just over 400kms with the B16. THAT'S A LOT! And I'm now running 92 vs 87 on top of that!
So, as you said, this would be the best of both - great fun around the city and less stress (in my case) and (again in my case) better fuel economy.
So again, if you don't mind sharing;
WHERE did you get the work done?
How pricey is it?
How long is the job?
FYI; I never had a problem shifting from 2nd to 3rd unless it was driver error. (missed shift)
My problem is that I will pop out of FITH gear. Weird. Go through the gears normally, hit 5th, goes in, cruise a few meters, then it pops out...?? Put it back in 5th and it stays. Stop at a light, repeat, POP. wtf??! And not everytime though - ??? and doesn't matter HOW I'm driving or the temp.
WHO did the work for you for this tranny?
I swapped out my LS tranny for a B16 when I swapped in my b20vtec. In the city, especially going down a good hill from a stop, I freaking LOVE this tranny!!! LOVE IT!!! Nothing like rowing through those gears quickly and listening to the engine and feeling the response. LOVE IT!!!
BUT, I HATE it on the highway. HATE IT!!!! I FREAKING HATE IT! Do you how many times I've unconsciously reached down and shifted OUT of 5th looking for that MISSING 6th gear. I drive 90kms one way each day to work on the 401 and I keep worrying that 1 day my engine is just gonna blow up running at a sustained 5000 rpm for so long.
Though I DO still love having the responsiveness when passing without having to gear down, but I'd happily sacrafice that since I usually gear down anyway to pass - JUST CUZ I CAN! lol I love BLOWING by someone rather than just passing. Yeah, that was me! lol
Recently I've heard of the LS 5th gear and I've been given this a lot of thought. A LOT.
I went from over 500kms (close to 600kms with my LS and b18b1) a tank down to just over 400kms with the B16. THAT'S A LOT! And I'm now running 92 vs 87 on top of that!
So, as you said, this would be the best of both - great fun around the city and less stress (in my case) and (again in my case) better fuel economy.
So again, if you don't mind sharing;
WHERE did you get the work done?
How pricey is it?
How long is the job?
FYI; I never had a problem shifting from 2nd to 3rd unless it was driver error. (missed shift)
My problem is that I will pop out of FITH gear. Weird. Go through the gears normally, hit 5th, goes in, cruise a few meters, then it pops out...?? Put it back in 5th and it stays. Stop at a light, repeat, POP. wtf??! And not everytime though - ??? and doesn't matter HOW I'm driving or the temp.
02-03-2011, 03:45 PM
#21
Nanmike Since you drive so many clicks on the highway this would be a great idea to do. I think it was Dave's mechanic John that did this work if I'm not mistaken. He will post his number on the thread if that was the same mechanic that did this work.
02-04-2011, 08:02 AM
#22
n00b
Join Date: Jun 2010
Location: Bowmanville
Posts: 45
This would be IDEAL! I couldn't stop thinking about it while cruising in to work this morning. At 120km, I'm just over 4000rpm.
Not where I want to CRUISE at, regardless of whether the motor is built or not.
So I will keep an eye out for Dave's mechanic's info unless someone on here can suggest another guy that can do this for me. I'm not sure if my mechanic (Altech Performance) does this type of tranny work.
Not where I want to CRUISE at, regardless of whether the motor is built or not.
So I will keep an eye out for Dave's mechanic's info unless someone on here can suggest another guy that can do this for me. I'm not sure if my mechanic (Altech Performance) does this type of tranny work.
02-04-2011, 08:37 AM
#23
Thanks for the reply. It was, as Paul mentioned, my mechanic that did the work. His name is John at JC Autoworx in Woodbridge. His rates are very reasonable, and his work is great. I cant say how much it will be, since the tranny I bought was already apart on his bench, it was just a matter of ordering the 5th gear ($190 or so). I encourage you to give him a call, and discuss your options, and pricing. Let him know David with the tranny swap sent you. His number is 905-265-2132.
The fact of the matter is, a b16 transmission, due to its final drive, will be keeping your rpms up in that ballpark. The LS 5th, however, coupled with the LS ring gear makes for the very tall and low revving gear. Combining the two, Ls 5th with b16 ring gear, still puts you somewhat higher but lower than it otherwise would be with the b16's 5th gear. It drops you by approximately 700 Rpm. It is the best of both worlds.
Cheers
The fact of the matter is, a b16 transmission, due to its final drive, will be keeping your rpms up in that ballpark. The LS 5th, however, coupled with the LS ring gear makes for the very tall and low revving gear. Combining the two, Ls 5th with b16 ring gear, still puts you somewhat higher but lower than it otherwise would be with the b16's 5th gear. It drops you by approximately 700 Rpm. It is the best of both worlds.
Cheers
02-04-2011, 11:05 AM
#24
n00b
Join Date: Jun 2010
Location: Bowmanville
Posts: 45
Hey thanks a lot. i appreciate the info. I will actually call him this afternoon.
Question, and forgive me since I'm not really familiar too much with the internal workings of a transmission, do I have to use the b16 ring gear? If I do not, will it drop my RPM's even further than by 700 rpm?
Question, and forgive me since I'm not really familiar too much with the internal workings of a transmission, do I have to use the b16 ring gear? If I do not, will it drop my RPM's even further than by 700 rpm?
02-04-2011, 11:25 AM
#25
Hey thanks a lot. i appreciate the info. I will actually call him this afternoon.
Question, and forgive me since I'm not really familiar too much with the internal workings of a transmission, do I have to use the b16 ring gear? If I do not, will it drop my RPM's even further than by 700 rpm?
Question, and forgive me since I'm not really familiar too much with the internal workings of a transmission, do I have to use the b16 ring gear? If I do not, will it drop my RPM's even further than by 700 rpm?
If I may, I'll use the common bicycle as an analogy. Consider that this bicycle in question has: 2 gears on the pedal side, which we'll call the front, and say 5 gears for arguments's sake on the back. If you are in the smallest gear on the front, you have a very powerful, but short 5 back gears. This is effectively the b16 transmission from the factory. If, however, on the front gearset you go up one to the slightly bigger one, your 5 back gears will not have as much torque (given that you can only put out so much force pedaling) but it will carry you to a higher top speed. This, in our example, with the second gear on the front, is the LS transmission from the factory.
What you are asking, then, is if you go from the first gear to the second gear, is it the same effect? The answer is no, since your ring gear choice greatly affects the torque multiplication that can be achieved on the whole by the transmission, and in turn the speeds and torque that can be generated.
Remembering the basic gear ratio theory, consider one small gear (called the "pinion") and one big gear (called the "spur"). To get more torque, you have one of two options. You can drop a couple teeth in the pinion gear, increasing the ratio (meaning more turns of the small gear for one turn of the big gear) or, increase the number of teeth on the spur gear, to the same effect. The opposite is also true, to get more top speed, at the expense of torque, you can increase the size of the pinion gear or decrease the size of the spur.
This helps us understand why the b16 transmissions are different from the LS ones. That ring gear is your spur gear, and also from our previous example the gear used from the front gearset on a bicycle.
Changing the 5th gear out of a B16 transmission for an LS 5th keeps the same ring gear that the b16 comes with (for the torque multiplication) through the first 4 gears. It effectively stretches your 5th and drops rpm by increasing the number of teeth on the gear you changed out.
It is important to remember that between the two transmissions the 5 gears are slightly different also, but I was explaining under the assumption that they are the same to understand the effects any changes will do.
Below is an actual picture of the LS transmission I swapped out of my Integra to connect the theory to the picture. In the case of the transmission, the ring gear also contains the differential.
And here is a picture of the gear ratios graphed out, using Fatboy Race Work's calculator - with the first being the LS transmission and the second being the B16. Stock tire sizes and redlines are used for comparison's sake.
This all above is my understanding of how this all works. What you are doing with the LS 5th in the B16 transmission is placing yourself somewhere inbetween the red and green lines on the 5th gear. Horray for interchangeable parts!
I hope this helps!
Dave
02-04-2011, 12:30 PM
#26
n00b
Join Date: Jun 2010
Location: Bowmanville
Posts: 45
Holly ----, Neon!!! Holly explaining, Batman!
It couldn't be clearer now to me if I tripped and fell into an open working tranny!!! lol
The bicycle was a perfect illustration!
You explained that perfect!
And the graph makes me see where I will be now when in 5th.
Thanks a million!!!!!!!!
Now, I have 2 stupid questions. The first one I think I know the answer to. The second one is just more out of curiousity than anything else.
Question #1.
Assuming the whole tranny has to be dropped in order to switch out the 5th gear to a LS 5th, would it not just be as easy to swap in a RSX 6spd tranny instead or (and this is the real question) will the RSX 6spd match up to my B20?
Question #2. (scenario)
So I'm cruising along the 401 doing about 120kms with the new LS 5th gear. All is good.
Then I come up on soccer mom doing 90km in her minivan. I sit on her *** for a while but she doesn't get the hint. Now I'm irritated. So I finally decide to just go around her - in STYLE! So I drop her down to 3rd and mash the pedal and scream past her!
QUESTION - In this scenario, would this be worse on my engine/tranny or easier on it. I'm now going from a lower LS rpm to a much higher b16 rpm in one move. My engine goes from purring to screaming.
Do you follow my question? Last thing I want is to leave my transmission behind on the 401...lol
It couldn't be clearer now to me if I tripped and fell into an open working tranny!!! lol
The bicycle was a perfect illustration!
You explained that perfect!
And the graph makes me see where I will be now when in 5th.
Thanks a million!!!!!!!!
Now, I have 2 stupid questions. The first one I think I know the answer to. The second one is just more out of curiousity than anything else.
Question #1.
Assuming the whole tranny has to be dropped in order to switch out the 5th gear to a LS 5th, would it not just be as easy to swap in a RSX 6spd tranny instead or (and this is the real question) will the RSX 6spd match up to my B20?
Question #2. (scenario)
So I'm cruising along the 401 doing about 120kms with the new LS 5th gear. All is good.
Then I come up on soccer mom doing 90km in her minivan. I sit on her *** for a while but she doesn't get the hint. Now I'm irritated. So I finally decide to just go around her - in STYLE! So I drop her down to 3rd and mash the pedal and scream past her!
QUESTION - In this scenario, would this be worse on my engine/tranny or easier on it. I'm now going from a lower LS rpm to a much higher b16 rpm in one move. My engine goes from purring to screaming.
Do you follow my question? Last thing I want is to leave my transmission behind on the 401...lol
02-04-2011, 04:08 PM
#27
Thanks for the kind words. It's always nice to see your explanations helping people.
In answer to your first question, yes the whole transmission does have to be dropped and then disassembled to get at the 5th gear. Unfortunately, you can't use a K-series transmission on a B-series Honda. The interchangeability of engine and related parts only really applies to those of the same series, in our case B(16, 18, 20). You have to stick with more or less what you have.
As for the second question, given the perceived soccer mom status, you now have to gather some horses and fly past her, leaving in your dust of disapproval. The LS 5th gear swap will still keep your B16 gears 1-4, so everything else stays the same. It will not affect your third gear, but it will alter the final drive ratio of the transmission as a whole slightly on paper.
Moreover, about which situation is better for your engine, it is the situation that doesn't involve you downshifting. I rarely find that you have to downshift to third at about that speed to pass someone. But, given that you would want to be flying past her, and I'm assuming here you're looking to compare LS to B16 transmissions - there's only one real difference that affects the answer to the question - which is where the RPM's are on your engine. Since the LS transmission is longer, you'd be putting it (at 90 km/h) a lot lower in the rev range than you would with the B16 going into third. So in that sense, less RPM is likely better for your engine.
But that's sort of off the point, because with the LS 5th you wouldn't be changing any of these gears except the fifth, so as long as you don't downshift from a speed too high for a given gear, you'd be fine downshifting either way (however it does put more stress on the engine at higher RPM's if you want to compare lower to higher).
Hope that offers some insight!
In answer to your first question, yes the whole transmission does have to be dropped and then disassembled to get at the 5th gear. Unfortunately, you can't use a K-series transmission on a B-series Honda. The interchangeability of engine and related parts only really applies to those of the same series, in our case B(16, 18, 20). You have to stick with more or less what you have.
As for the second question, given the perceived soccer mom status, you now have to gather some horses and fly past her, leaving in your dust of disapproval. The LS 5th gear swap will still keep your B16 gears 1-4, so everything else stays the same. It will not affect your third gear, but it will alter the final drive ratio of the transmission as a whole slightly on paper.
Moreover, about which situation is better for your engine, it is the situation that doesn't involve you downshifting. I rarely find that you have to downshift to third at about that speed to pass someone. But, given that you would want to be flying past her, and I'm assuming here you're looking to compare LS to B16 transmissions - there's only one real difference that affects the answer to the question - which is where the RPM's are on your engine. Since the LS transmission is longer, you'd be putting it (at 90 km/h) a lot lower in the rev range than you would with the B16 going into third. So in that sense, less RPM is likely better for your engine.
But that's sort of off the point, because with the LS 5th you wouldn't be changing any of these gears except the fifth, so as long as you don't downshift from a speed too high for a given gear, you'd be fine downshifting either way (however it does put more stress on the engine at higher RPM's if you want to compare lower to higher).
Hope that offers some insight!
02-04-2011, 04:53 PM
#28
n00b
Join Date: Jun 2010
Location: Bowmanville
Posts: 45
Thanks, that DOES clarify things. I was pretty sure that the k and b series were not interchangeable, but I was hoping that if you could drop a K series into a B series body, then maybe (with some modification), you could hook up a K series tranny to a B series motor.
So I guess the trick now is to try and locate this LS 5th gear.
I'm allergic to dealerships!
So I guess the trick now is to try and locate this LS 5th gear.
I'm allergic to dealerships!
02-05-2011, 01:03 PM
#31
Thanks guys! I try to be a help.
The meaning of life? Haha some philosophy courses at Ryerson University should be able to answer that!
But it does, I'm sure, have something to do with driving a teg
The meaning of life? Haha some philosophy courses at Ryerson University should be able to answer that!
But it does, I'm sure, have something to do with driving a teg
10-12-2011, 10:39 PM
#32
Re: Transmission Swap Review - LS versus SIR with LS 5th
UPDATE!
October 2011.
25,000 kilometers since swap.
It's been a while, and I remembered this thread so I thought I'd post an update on how it's all been with the transmission and clutch combo.
Thus far, absolute bliss as far as driving the car is concerned, and the clutch has held up beautifully all this time. It's all worn in seamlessly and butter smooth is the only way I can describe its current state.
It's been 25,000 kilometers and nearly a year, and I don't remember what it's like to have longer gears anymore. I will say though, that the more useable power has proven to be tons of fun throughout my driving and I've changed a number of people's opinions on the potential of more-or-less stock honda's. The highway passing power is great, downshift to fourth puts you smack in the middle of the powerband and roars all the way to redline in a swift wave of acceleration and untamed emissions in part due to my quickly failing cat, and my slowly aging motor.
All in all, the smoothness, power delivery and fun together make this undoubtedly THE best mod I've done to date (and there's been many up till this year).
Second runners up are the Recaro seats that make the car aesthetically and in comfort, and third are the lower tie bars, courtesy of Pat, coupled with the ITR suspension on Tein's for the handling dynamics I've so grown to know and love.
Cheers all,
Dave
October 2011.
25,000 kilometers since swap.
It's been a while, and I remembered this thread so I thought I'd post an update on how it's all been with the transmission and clutch combo.
Thus far, absolute bliss as far as driving the car is concerned, and the clutch has held up beautifully all this time. It's all worn in seamlessly and butter smooth is the only way I can describe its current state.
It's been 25,000 kilometers and nearly a year, and I don't remember what it's like to have longer gears anymore. I will say though, that the more useable power has proven to be tons of fun throughout my driving and I've changed a number of people's opinions on the potential of more-or-less stock honda's. The highway passing power is great, downshift to fourth puts you smack in the middle of the powerband and roars all the way to redline in a swift wave of acceleration and untamed emissions in part due to my quickly failing cat, and my slowly aging motor.
All in all, the smoothness, power delivery and fun together make this undoubtedly THE best mod I've done to date (and there's been many up till this year).
Second runners up are the Recaro seats that make the car aesthetically and in comfort, and third are the lower tie bars, courtesy of Pat, coupled with the ITR suspension on Tein's for the handling dynamics I've so grown to know and love.
Cheers all,
Dave
10-13-2011, 08:10 PM
#34
Re: Transmission Swap Review - LS versus SIR with LS 5th
WOW you only drove 25,000kms
Since the paint job in may i put in 25,000Kms!!! GAWDAMN
Glad to see its all good. I've actually been hitting up John for a bunch of work recently. He does great work
Since the paint job in may i put in 25,000Kms!!! GAWDAMN
Glad to see its all good. I've actually been hitting up John for a bunch of work recently. He does great work
10-14-2011, 09:14 AM
#35
Re: Transmission Swap Review - LS versus SIR with LS 5th
Lol I haven't been doing as much cruising lately and meet attendance, as you all know 
It's treating me great still, I'm very happy with it and would recommend it to anyone anyday.
As for John, yeah he's been great as always, I'm always happy to take the car to him. I did the timing belt/water pump recently. Apparently it had never been done before, and the water pump was the original. And leaking. Good timing! Go figure
It's treating me great still, I'm very happy with it and would recommend it to anyone anyday.
As for John, yeah he's been great as always, I'm always happy to take the car to him. I did the timing belt/water pump recently. Apparently it had never been done before, and the water pump was the original. And leaking. Good timing! Go figure