okay well im planning on buying a ZC for my std soon and i need a lil info. im just going to buy the complete engine. i have a D15b1 with a Si tranny and no intermediat shaft. well i want an itermediate shaft tel help compensate for the torque steer and the long *** axle i have. so what would i need. i still have the stock STD hubs. oh just a quicky reminder can i use a PM6 ecu for the DOHC ZC

 

not sure on the half shaft but your gona need dx or si hubs.

 

i ran the dohc zc with an si trans and no intermediate shaft no problem. so u should b fine there. The pm6 will run the car fine but for the best performance get the pg7 from a 88-89 integra as soon as u can. And you CAN use your hubs as long as u use your stock axles.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Skunk U &raquo;</TD></TR><TR><TD CLASS="quote">i ran the dohc zc with an si trans and no intermediate shaft no problem. so u should b fine there. The pm6 will run the car fine but for the best performance get the pg7 from a 88-89 integra as soon as u can. And you CAN use your hubs as long as u use your stock axles. </TD></TR></TABLE> listen to this guy

 

but if you want intermediate shaft you will need zc tranny axles and intermediate shaft and si/dx hubs

 

Evidently there is a lot of speculation on intermediate shafts for the ZC tranny.

Obviously the one you'd want would be from the JDM DOHC ZC, which is rare as hell. I had one not too long ago, but I sold it. I did take pics and post them to verify it was the correct one, and it looks like this:



Tranny end:



Left axle inner joint pops in here:





Some people say that a combination of mix and match mutt axles and the RT4WD manual tranny intermediate shaft works with the DOHC ZC tranny, but I don't know the exact combo.

I say screw the crappy ZC tranny anyways. If you get the ZC tranny build yourself a super D tranny like I did. I took the ZC 1-4 gears, and out them into the Si case while using the Si 4.25 FD and the Si 5th gear for highway rpm.

I had this tranny with stock unequal length axles mated to an 11:1CR D16A6 that beat down every DOHC ZC I've ever driven and it didnb't torque steer like crazy.

The ZC tranny is a turd. It has close gearing, but the DX-spec 3.88 FD, which basically makes each gear laborious to rev through. Even a box stock Si tranny is better for acceleration.

 

BTW I'm going to copy/paste another bit of info I posted on another forum when we were discussing ZC trannies and gearing - begin paste:

Actually the ZC tranny, if it came from a DOHC ZC has completely different gearing and final drive than the 88-91 Si tranny.

The DOHC ZC tranny has the closest 1-5 gearing than any other SOHC tranny. The "problem" with them is that they also have the DX spec taller 3.88 final drive in them.

The 88-91 Si tranny has longer, more spaced out gearing, but a much better 4.25 final drive in them, so OVERALL after multiplying gears against the final drives the Si tranny is actually SHORTER/BETTER geared than the ZC tranny.

What I have done, and it works out amazingly well, is I took ZC 1-4 gears and stacked them into an Si tranny case with the better Si final drive - but I left the stock Si 5th gear!!! What this gave me was a ultra close, awesome accelerating 1-4 gear ratio, but a stock 88-91 Si 5th gear for highway cruising rpm.

Let me ask you this:

Currently do you have the DOHC ZC tranny complete with the midshaft, or have I gone off on a tangent for nothing? The reason I ask is that the DOHC ZC L3 tranny is 100% different inside than the SOHC L3 ZC tranny.

For comparison's sake here's the actual ratios:

JDM DOHC ZC L3:

1st - 3.250

2nd - 1.944

3rd - 1.346

4th - 1.033

5th - 0.878

Final drive - 3.888

I bolded 5th because that's shorter than a USDM Type R 5th gear ratio!!! Now when you do the math against the 3.88FD it's not too crazy though - you get 3.40.

Now for USDM Si or JDM SOHC ZC L3 ratios:

1st - 3.250

2nd - 1.894

3rd - 1.259

4th - 0.937

5th - 0.771

Final drive - 4.250

I bolded the final drive because it's the best one we got here in a regular 5-speed L3 tranny here. When you multiply the 4.25Fd against the .771 lower 5th gear you get 3.27 - still lower than the DOHC ZC overall 5th gear ratio. This means the USDM 88-91 Si tranny has a slightly lower cruising highway rpm in 5th gear.

So basically acceleration would be in direct correlation with how close each gear is to each other, because the less of a number difference between the gears, the less rpm drops, and the higher each overall gear number ratio is (gear ratio x final drive ratio) the quicker you get to rip through that gear.

Sorry if I'm confusing anyone

I'm going to try and do the math of my custom Zc/Si hybrid tranny where i used ZC 1-4 closer gearing coupled with the Si 5th and 4.25 FD to sow you what I mean. I will simply take each gear ratio and multiply it against the 4.25 FD to get my overall gear ratios per gear.

1st - 13.81 (same as 88-91 Si tranny either way)

2nd - 8.26

3rd - 5.72

4th - 4.39

5th - same 3.27 since I kept the Si 5th gear, but if I had kept the ZC 5th it'd be a ridiculous 3.73!!! That's a huge difference!

Anyways see how close each number is? Like I said the closer the numbers stay together, the quicker you rip through each gear, and thus, the quicker you accelerate.

For comparison's sake I'll do the same math with a regular 88-91 Si tranny that most of us try to get when we do a SOHC build here in the US:

1st - 13.81

2nd - 8.04

3rd - 5.35

4th - 3.98

5th - 3.27

And finally the DOHC Zc with it's shorter gearing, but shitty 3.88 DX-spec FD:

1st - 12.61 (YIKES! Would take longer to go through!)

2nd - 7.54

3rd - 5.22

4th - 4.00

5th - 3.40

So compare the numbers and see the difference? You'll note that the custom Zc/Si tranny has higher numbers, and closer to each other numbers too. This means quicker ripping through gears.

You'll also note that even our regular 88-91 Si tranny has a clear advantage over the JDM DOHC ZC tranny too, because of the taller 3.88 FD they have. The taller FD negates the closer gears.

Does that make sense?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tico &raquo;</TD></TR><TR><TD CLASS="quote">o... with a Si tranny and no intermediat shaft. well i want an itermediate shaft tel help compensate for the torque steer and the long *** axle i have. so what would i need... </TD></TR></TABLE>


My experience is that the ZC intermediate shaft has a larger diameter than the Si axles, so most likely you would need to install a differential that can accept the larger diameter axle shaft of the ZC.

I ran across this with my CRX. I bought the ZC trans and installed a Si LSD and had to install Si axles, because the ZC intermediate shaft would not fit into the Si LSD - to large.

What's fair market value for the intermediate shaft?

 

spend some time in the Transmission forum over at Dseries.org, i guarantee you'll find your answer there.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C5-EH2 &raquo;</TD></TR><TR><TD CLASS="quote">Evidently there is a lot of speculation on intermediate shafts for the ZC tranny.

Some people say that a combination of mix and match mutt axles and the RT4WD manual tranny intermediate shaft works with the DOHC ZC tranny, but I don't know the exact combo.
</TD></TR></TABLE>you are correct - there is a lot of different information on what works - the only intermediate shaft that works with the JDM DOHC ZC engine and the ZC transmission is the JDM ZC intermediate shaft

there was speculation that possibly the bracket from the 88-91 4WD wagon intermediate shaft in combination with the 86-89 Integra D16A1 shaft would work with the ZC - it won't - the D16A1, ZC and 4WD wagon shafts themselves are all the same, but the brackets are all different - the D16A1 bracket has a different bolt pattern and won't bolt to the ZC block - the 4WD bracket bolts right onto the block but is different in that the distance from the centerline of the shaft to the centerline of the 2 bottom attaching holes is shorter than the distance on the ZC bracket by about 1/2" causing the shaft to sit up too high to fit into the transmission - it is about 1/2" too high

this is the ZC bracket:



this is the 4WD bracket:




Modified by jlicrx at 7:46 PM 8/12/2008

 

I'm currently running a DOHC ZC transmission with Si final drive/EG EX differential(soon to be ZXi 4.437 FD). Best/easiest way to get rid of torque steer is to just get a LSD.

 

okay sounds good. well i have another question. since im using my stock trans what clutch can i use with my Si trans and the ZC motor

 

the clutch you need depends on the year of your transmission and the year of the flywheel you have - what year and model is your car?

 

well its 88 std. the previous owner had bought it with it like that. he told me he didnt know what year the tranny is so im stuck

 

count the splines on the input shaft of the tranny

 

you will need to wait until you get the engine and transmission out so that you can see what you have before you buy the clutch

 

alright koo. is there any other way to tell besides the imput shaft?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tico &raquo;</TD></TR><TR><TD CLASS="quote">alright koo. is there any other way to tell besides the imput shaft?
</TD></TR></TABLE>no

 

I have a 90 hatch and have been threw a few transmissions. Between all of them (or at least what I've read on other sites), the DOHC ZC transmission has the best gears, but not so great of a final drive. The Si I believe has the same final drive as the ZC too from what I've read (3.88). I know the DX diff. is about 4.11 because I took one apart at school one time and counted the gears. What I'm getting at is the DOHC ZC transmission with the DX final drive diff. would make a really close ratio transmission, one I've built and used before. The down side is you'll be spinning about 4-5 thousand rpm's going down the freeway at about 60-65 in 5th, but the positive is you'll be in the power band of your motor every shift of a race. That's the set up I ran and loved it. As far as the torque steer problem, I would just get an LSD. Look on JEGS for one. Last time I checked I think they were about $250 for a D series one.

 

okay thats very helpful but my problem is that thiss is my DD. its my only car and i want to do my first swap in it so i chose the DOHC ZC simplicity and price wise but i dont need a tranny. my 5spd is in great condition and is smooth as glass. i know i could probably get away using my stock clutch but i figured while im there what the hell replace it. thats really the only thing keeping me from doing this swap

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HaulingAddison &raquo;</TD></TR><TR><TD CLASS="quote">I have a 90 hatch and have been threw a few transmissions. Between all of them (or at least what I've read on other sites), the DOHC ZC transmission has the best gears, but not so great of a final drive. The Si I believe has the same final drive as the ZC too from what I've read (3.88). I know the DX diff. is about 4.11 because I took one apart at school one time and counted the gears. What I'm getting at is the DOHC ZC transmission with the DX final drive diff. would make a really close ratio transmission, one I've built and used before. The down side is you'll be spinning about 4-5 thousand rpm's going down the freeway at about 60-65 in 5th, but the positive is you'll be in the power band of your motor every shift of a race. That's the set up I ran and loved it. As far as the torque steer problem, I would just get an LSD. Look on JEGS for one. Last time I checked I think they were about $250 for a D series one. </TD></TR></TABLE>

Your numbers are off. The DX final drive is a 3.88, same as the DOHC ZC. The Si's are 4.25.

Also, the revs is more like 4000rpm is about 70mph with 195/60-14's. I know this from first-hand experience. I should note that I was still able to get 57mpg hwy(cammed/bolt-on D15B VTEC in a stripped 88 HB).

The LSD Jeg's probably carries is a Phantom Grip. Do a search on them and you'll see why you do not want to run them(more commonly known as "Phantom Slip".

 

I have a PG7 ecu for sale if you need one! Check my FS thread or PM me.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HaulingAddison &raquo;</TD></TR><TR><TD CLASS="quote">I have a 90 hatch and have been threw a few transmissions. Between all of them (or at least what I've read on other sites), the DOHC ZC transmission has the best gears, but not so great of a final drive. The Si I believe has the same final drive as the ZC too from what I've read (3.88). I know the DX diff. is about 4.11 because I took one apart at school one time and counted the gears. What I'm getting at is the DOHC ZC transmission with the DX final drive diff. would make a really close ratio transmission, one I've built and used before. The down side is you'll be spinning about 4-5 thousand rpm's going down the freeway at about 60-65 in 5th, but the positive is you'll be in the power band of your motor every shift of a race. That's the set up I ran and loved it. As far as the torque steer problem, I would just get an LSD. Look on JEGS for one. Last time I checked I think they were about $250 for a D series one. </TD></TR></TABLE>


Did you happen to miss my highly detailed gearing charts listed earlier in this very topic?

I already told him the ideal tranny to build from stock Honda parts.

 

i think he did... im glad i ran across this thread though... im staying with my single cam and was wanting to know about gearing as far as the single cam trannys go. thanks for the info.

oh yea... pm7 ftw

 

one more quick question... would any gearing from the 4spd trannys be good for boost? just a question i wanted to ask. sorry to thread jack. i had to ask though