I'm buying a ZC engine for my 1991 civic hatch dx and I was wondering which transmission I should buy. I don't want to use the dx trans b/c it sucks. Should I just use the ZC since I can buy one or try to find an Si one. I can't seem to find an Si one so I figured I would settle for the ZC but how does the ZC perform?

 

Si transmissions are usually a lot easier to find than ZC's. But if you do find a zc tranny, go with it, im pretty sure theyre geared a bit shorter than an Si tranny. But dont go out of your way trying to find a zc trans, its very similar to an Si.

 

I have the ZC and ZC tranny, the ZC tranny is easy to get if you buy it with the engine, but I wasn't happy overall with mine. It depends on your style of driving, I am putting in an SI transmission Friday evening, but it will have a better overall gearing to my driving style. The JDM L3 (ZC Tranny) has a closer-ratio gearset that keeps my car above 4500 doing 65-70mph on the highway, and I do a lot of highway driving, plus I autocross so I don't need the close-ratio benefits that a drag racer might. It's up to you, but I have driven the ZC both ways, I preferred the SI tranny, just think in terms of your driving style.

 

well where can I get an Si tranny? I can't seem to find any yet

 

It took me a while to find one, I'd suggest you check all over classifieds, chat with other people, etc. I wouldn't pay more than $150 for one unless it's got a Quaife LSD or likewise in it (just my opinion).

 

ok, now do I need to buy new axles and anything else if I get the Si Tranny?

 

i got a zc tranny from a shop for $100 and a zc tranny and SI motor for $75. a little whiel ago i picked up a SI tranny for $25. just get somethign for now but when you see zc trannys for sale or si pick them up and keep them on the side because the day your tranny goes bad adn you dont have one you will pay anythign for a tranny just to get your car running again.

 

also i forgot to mention one thing. pick a tranny you wanan stick with. if you get a $300 performance clutch for a si it wont work on a zc and a zc clutch wont work on a si. so be sure you know wat tranny you want before you do anythign with a clutch.

 

To answer your question, your DX axles will work with the SI tranny. If you use the ZC tranny, you'll need a ZC halfshaft, and a pair of 90-93 Integra Axles and "hybrid" them with your civic outer hubs.

 

it is actually easier to get a ZC tranny Vs. an Si tranny. HMO has ZC trannies for cheap

 

[QUOTE=cell7dotORG]The JDM L3 (ZC Tranny) has a closer-ratio gearset that keeps my car above 4500 doing 65-70mph on the highwayQUOTE]
true, the ZC has closer ratio and lower gearing than Si for gears 2 thru 5, but when you take into account the Si 4.25 final drive versus the ZC 3.888 final drive, you will find you are turning more rpm at the same speed in gears 2 and 3 with the Si tranny, and essentially the same in 4th - in fifth gear only the ZC will be turning slightly higher (about 4%) - the best bet for lower rpm in 5th is the ZC with the 5th gear from the Si (about 9% less than the Si)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by durrett syndrome &raquo;</TD></TR><TR><TD CLASS="quote">also i forgot to mention one thing. pick a tranny you wanan stick with. if you get a $300 performance clutch for a si it wont work on a zc and a zc clutch wont work on a si. so be sure you know wat tranny you want before you do anythign with a clutch.</TD></TR></TABLE>
Not exactly true, the clutch fits the number of splines on the shaft, as long as the number of splines on the ZC tranny match the number of your previous tranny your all good.

 

all dohc ZC's have the 20 spline input shaft and flywheel for 200mm dia. disc, same as 89 civic/CRX - if you change to 90-91 civic/CRX flywheel you can use 90-91 clutch

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 91hatchnewb &raquo;</TD></TR><TR><TD CLASS="quote"> I don't want to use the dx trans b/c it sucks. ?</TD></TR></TABLE>
they dont suck.....
i will sell u an Si final drive and differential..... that way u can make that DX an Si.... at the same time u can change the diff pin and have a fresh good differential... that way u dont brake it,.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jlicrx &raquo;</TD></TR><TR><TD CLASS="quote">all dohc ZC's have the 20 spline input shaft and flywheel for 200mm dia. disc, same as 89 civic/CRX - if you change to 90-91 civic/CRX flywheel you can use 90-91 clutch</TD></TR></TABLE>
Do you have a ZC? The DOHC ZC Transmission (JDM L3) is 21 spline, all of them are. All of the information you need can be found on this page http://dmoore.com/crx/tranny.htm

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by cell7dotORG &raquo;</TD></TR><TR><TD CLASS="quote">
Do you have a ZC? The DOHC ZC Transmission (JDM L3) is 21 spline, all of them are. All of the information you need can be found on this page http://dmoore.com/crx/tranny.htm</TD></TR></TABLE>yes, i have a ZC, several in fact - we have a shop here in Colorado specializing in ZC's - http://www.ZCspeed.com - the transmissions are all 20 spline, not 21 - dmoore.com is a good site for ZC info and if you look, you will see that ZC is 20 spline

 

Integra (all) - Transmission Model
ZC - Engine
86 - 89 - years
200 - flywheel and clutch size in MM
7-7/8 - flywheel and clutch size in inches
21 - # of splines on the tranny
7/8 - tranny shaft size

It's all right there on the page, second table, right on the top, plus, I am holding the clutch in my hand right now, it's 21 spline. If you got a newer ZC tranny it may be 20 spline, but I am letting you know right now that not all are 20 spline, unless I have some sort of special one of a kind super-special top-secret transmission. Not trying to flame but I ran into the spline problem when I first put it in, but 91 Clutch & Flywheel woudn't work so I had to use the ZC ones that came with the transmission.

 

i don't doubt that you have one with 21, but we have had nearly a dozen here in the shop in the last two years that have all been 20 spline and have never had one with 21 and they all have had the 200mm disc, same as 89.