transmission Swapping

[Xero]

okay, I know we talked about this in another thread a little while back, just wanna bring it back to the light.

I remember someone stating that looking at the gear ratios of the S13 Redtop SR, those gears would see better use in the CA18. Has anyone really looked at the gear ratios and agreed with this?

What about maybe, JUST MAYBE, a S15 6-speed? I just think 6 speeds are cool. Stupid, pointless, and not worth the money, but cool, come on...I'm fighting for the "Mad Scientist of NICO" award here

I'll get the gear ratios in a couple minutes, so we can actually see the actual ratios for reference,

[Xero]

CA18DET:1st: 3.3212nd: 1.9023rd: 1.3084th: 1.0005th: .838Reverse: 3.382Final Drive: 4.363

S13 Redtop:1st: 3.3212nd: 1.9023rd: 1.3084th: 1.0005th: 0.759Reverse: 3.382Final Drive: 4.083

S14 Blacktop:1st: 3.3212nd: 1.9023rd: 1.3084th: 1.0005th: 0.759Reverse: 3.382Final Drive: 4.083

S15 Blacktop:1st: 3.6262nd: 2.2003rd: 1.5414th: 1.2135th: 1.0006th: 0.767Reverse: 3.437Final Drive: 3.692

[nomore_mr2]

the s15 6 speed wont work i already tried heres why. the ca and s13-14 motors are 2 pieces. the s15 is a 3 piece design. when mating a sr20 gear box to a ca18 bell housing its simple unbolt the ca18 bell housing and mate to gear box. but since they used the 3 pieces in the later model its not interchangeable. also the s14 motor has better syncro's so if you were gonna do a ca/sr hybrid transmission try for a s14 gear box otherwise the s13 is good.

[Xero]

so why do they put the S14 SR transmission on S15 SR20's in Japan?

but that's actually getting into IMPLEMENTING the idea, I'm just brain storming, I'll only do it if it was really worth it, i.e., the gear ratios don't get much better for how the CA makes its power.

[nomore_mr2]

idk maybe cuz the sr20's share the same bell housing where the ca nad the sr20 dont share the same bell housing.

[dan240]

don't shoot me, but i read somewhere before that the Miata's 6 speed transmission is the same as / could work with the ca18det as long as you change the bellhousing. I checked, and the gearing is different, but maybe somebody has a conclusive word on this. It seems very unlikely, but at the same time, it'd be worth checking out.

Thanks

[Xero]

The thing is, I don't want to JUST do a 6-speed swap, I want to do a transmission conversion that will better suit the way that the CA18 makes its power. A transmission that'll better suit my needs, I figured that one of the many SR gear sets would be better suited for the CA as was hypothesized by a member in a different thread,

[Bizz]

Here's somthing to think about.

CA18et1st 3.592 2nd 2.057 3rd 1.361 4th 1.000 5th 0.821 reverse 3.657Final Drive is either 4.11 or 4.36 depending on who you ask.

Watch that third step....it's a doozy.

[chezina]

Xero where did u get the gear ratios?IN the FSM for the S14 i downloaded at http://www.silviaaustralia.com/techinfo.asp the gear ratios are like this:S14 SR20DET:1st: 3.3212nd: 1.9023rd: 1.3084th: 1.0005th: .838Reverse: 3.382Final Drive:3,692 (3,916 for automatic)These are the same ratios u listed for the CA.

[Xero]

I got them from an New Zealand Silvia site,

http://www.nissansilvia.co.nz/...e.htm