4-Speed/5-Speed SI Transmission HELP

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Ok, I am looking to figure out which Transmission will be best for what I'm trying to do.

Basically I have a 90 Civic DX Hatchback with a stock D15B2 and 5spd trans.

I have a 4spd trans out of a 90 Civc DX and a 5spd trans out of a 90 CRX Si sitting on the floor.

What I need to figure out is the Final Drive ratio's and gears that are in these transmissions

I am going to race it on a 3/8 mile asphalt oval track here in NY and I need the trans with the longest 3nd and 3rd gear

I can't find ANY information on the gearing in the 4spd, and I haven't had much luck locating any info on the stock 5spd.

Any help would be greatly appreciated, thanks!
 
what u should do is sell me that crx si tranny. i need one for a swap like really bad. the d15b2 will have longer gears. the si tranny has shorter gears obviously for acceleration.

the si tranny has a 4.25 final drive. idk about the 4 spd.
 
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L3TRANSMISSIONgears.jpg
 
One question about that chart ^^^^^Above^^^^^

The smaller the number the longer the gear correct???

So I would favor a 4 spd trans because 2nd and 3rd gears are longer?

Perfect, just the info I wanted!!! Thanks!

Also, that trans is going to cost at least $100 to ship to you, not even sure where your located, so its not worth me selling it for only $50....
 
I might be wrong, but you may need different axles to run the 4 speed trans. even if you'd want to.
 
HF is the only one with different axles. It has a different spline count on the hub, or was it to the transaxle.. I forget..
 
One question about that chart ^^^^^Above^^^^^

The smaller the number the longer the gear correct???

So I would favor a 4 spd trans because 2nd and 3rd gears are longer?

Perfect, just the info I wanted!!! Thanks!

Also, that trans is going to cost at least $100 to ship to you, not even sure where your located, so its not worth me selling it for only $50....

i'm located at 39466, how much do u want for it? lemme konw i need it for a d15b swap into a 90 civic hatch. thx
 
The HF has the same axles as the Standard Civic. The DX has the bigger outter hubs as the Si but the inner seal part on the tranny are different betweent he Dx and Si, so STD/HF axles are the same, DX are different, and Si are different.

If you're racing oval I would think the DX would be best for you. As you can see in the chart the actual gears in the DX and Si are the same, the final drive is what makes the Si the most desireable for most people. The final drives are the same in the 4 speed and the DX, but I would think you'd want a bit of lower acceration. The 4 speeds are complete pigs. Yet if you're looking for the longest 3rd gear then look for an HF tranny.
 
Thanks for everyone's help, I think I'm going to stick with the DX 5spd after all.

As for the SI tranny I have, I've got a guy locally willing to pay $250 for it, so if you can beat that, remember to include shipping from 14212 to you.

Thanks again guys!
 
hmm.....so $250 plus shipping? that's kinda high. lemme know if the local deal falls through. i think he'd be willing to pay $250 including shipping. idk u find out how much shipping would be n let me know.
 
He's willing to pay me the $250 and come pick it up, no shipping needed, I'll let you know what happens.

Its going to cost $105 to ship to you, so keep that in mind.
 
The HF has the same axles as the Standard Civic. The DX has the bigger outter hubs as the Si but the inner seal part on the tranny are different betweent he Dx and Si, so STD/HF axles are the same, DX are different, and Si are different.
DX and Si axles are identical - any of the axles will fit at the transmission end - all of the L3 transmissions, except for the ZC, have the same differential side gears where the axles go in - the ZC transmission uses an intermediate shaft and larger axles like the Integra - the large bearing transmission cases, like the Si, use a different seal than the small bearing cases, but the axles are all the same at the transmission end - the seals have the same inner diameter and different outer diameters
 
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