SR transmission possibilities - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

King 240 · 10-22-2006, 06:34 PM

I'm looking into easy to do transmission upgrades.
the closest one I'm considering right now is having a KA transmission rebuilt and put on the SR transmission bell housing. I've heard that this will give a better and taller 5th gear over the SR transmission..........true/ false?

2nd one is the 300ZX TT transmission, however I was told this should only be used in higher hp SRs as it will serve no purpose with the gearing, also there is a custom adapter plate that must be used.

S15 Silvia transmission.......6th gear awesome, but have read about the transmission crapping out around 400whp. One way to strengthen this transmission is to go with the OS-GIKEN gear sets and main shaft.

just looking for some insight if anyone has used any of these transmission setups.

ladiesman8527 · 10-23-2006, 08:21 AM

KA trannys are pretty easy to come by. just keep a spare or two lying around and just replace your SR tranny when the time comes. the OS Giken gear and shaft sets are like $4300!! you could buy like 20 KA trannys for that. im interested in having my KA spare tranny rebuilt and installin it on my SR. i wonder how much that would cost.

mikessilvia · 10-23-2006, 08:30 AM

Not to thread jack, but this past weekend I was installing the KA tranny. I noticed that it is about a 1/2" to an inch longer. Does anyone know if this will hurt anything? The half shaft going back in was quite an issue, also you have to make sure the tranny is in nuetral, so be careful putting the bell housing on. After installing the tranny the first time I had neutral which was first gear, and fifth gear which was neutral. But we figured out that it has to be in neutral when installing.

ladiesman8527 · 10-23-2006, 08:33 AM

it shouldnt be a problem. a friend of mine just put a KA gear box with SR bellhousing on his SR a few weeks ago and everything mounts and works fine.

mikessilvia · 10-23-2006, 08:40 AM

Quote:

Originally Posted by ladiesman8527

it shouldnt be a problem. a friend of mine just put a KA gear box with SR bellhousing on his SR a few weeks ago and everything mounts and works fine.

Cool, sounds great.

projectRDM · 10-23-2006, 09:09 AM

You can buy a rebuild kit for either unit online for about $320. I can't remember where I saw it, bit I googled it so it's easy to find.
That would be the cheapest way to ensure you have a perfect condition unit, but I'd also have another one as a spare since swapping a used one is quicker and costs less. Or, you could not drive like an ass and beat on it and it should last forever.

mikessilvia · 10-23-2006, 09:23 AM

Well the reason why I stress that you make sure it is in nuetral after the bellhousing is on is so you don't run into my problem. Because we put the Sr20 tranny back in thinking that something was bad wrong with the KA tranny. It did the same thing. That is where we came to the conclusion that it had to be in nuetral.

R34SKYLINE · 10-27-2006, 11:08 AM

Quote:

Originally Posted by King 240

I'm looking into easy to do transmission upgrades.
the closest one I'm considering right now is having a KA transmission rebuilt and put on the SR transmission bell housing. I've heard that this will give a better and taller 5th gear over the SR transmission..........true/ false?

Its true the KA has a 0.759 5th ratio vs the SR .0.838 ratio:

SR20 tranny with 0.838 5th gear ratio:

KA24 tranny with 0.759 5th gear ratio:

10-22-2006, 06:34 PM	#1
King 240 Banned from the Marketplace Join Date: Nov 2002 Location: College Station,TX Age: 40 Posts: 449 Trader Rating: (0) Feedback Score: 0 reviews	SR transmission possibilities I'm looking into easy to do transmission upgrades. the closest one I'm considering right now is having a KA transmission rebuilt and put on the SR transmission bell housing. I've heard that this will give a better and taller 5th gear over the SR transmission..........true/ false? 2nd one is the 300ZX TT transmission, however I was told this should only be used in higher hp SRs as it will serve no purpose with the gearing, also there is a custom adapter plate that must be used. S15 Silvia transmission.......6th gear awesome, but have read about the transmission crapping out around 400whp. One way to strengthen this transmission is to go with the OS-GIKEN gear sets and main shaft. just looking for some insight if anyone has used any of these transmission setups.

10-23-2006, 08:30 AM	#3
mikessilvia Join Date: Sep 2004 Location: Mobile, AL Age: 46 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Not to thread jack, but this past weekend I was installing the KA tranny. I noticed that it is about a 1/2" to an inch longer. Does anyone know if this will hurt anything? The half shaft going back in was quite an issue, also you have to make sure the tranny is in nuetral, so be careful putting the bell housing on. After installing the tranny the first time I had neutral which was first gear, and fifth gear which was neutral. But we figured out that it has to be in neutral when installing. __________________

10-23-2006, 09:23 AM	#7
mikessilvia Join Date: Sep 2004 Location: Mobile, AL Age: 46 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Well the reason why I stress that you make sure it is in nuetral after the bellhousing is on is so you don't run into my problem. Because we put the Sr20 tranny back in thinking that something was bad wrong with the KA tranny. It did the same thing. That is where we came to the conclusion that it had to be in nuetral. __________________

10-23-2006, 08:21 AM	#2
ladiesman8527 Zilvia Junkie Join Date: Dec 2005 Location: Collierville, TN Age: 38 Posts: 429 Trader Rating: (0) Feedback Score: 0 reviews	KA trannys are pretty easy to come by. just keep a spare or two lying around and just replace your SR tranny when the time comes. the OS Giken gear and shaft sets are like $4300!! you could buy like 20 KA trannys for that. im interested in having my KA spare tranny rebuilt and installin it on my SR. i wonder how much that would cost.

10-23-2006, 08:33 AM	#4
ladiesman8527 Zilvia Junkie Join Date: Dec 2005 Location: Collierville, TN Age: 38 Posts: 429 Trader Rating: (0) Feedback Score: 0 reviews	it shouldnt be a problem. a friend of mine just put a KA gear box with SR bellhousing on his SR a few weeks ago and everything mounts and works fine.

10-23-2006, 09:09 AM	#6
projectRDM Post Whore! Join Date: Dec 2002 Location: Atlanta Age: 51 Posts: 13,812 Trader Rating: (12) Feedback Score: 12 reviews	You can buy a rebuild kit for either unit online for about $320. I can't remember where I saw it, bit I googled it so it's easy to find. That would be the cheapest way to ensure you have a perfect condition unit, but I'd also have another one as a spare since swapping a used one is quicker and costs less. Or, you could not drive like an ass and beat on it and it should last forever.