what tranny is generally better to use on a DOHC ZC .. ive noticed alot of people use the si tranny.. not alot of people rock the zc tranny.. why is that? better gearing? or what.. im just wondering..

 

Si transmissions are more common so more people use them. Plus their gearing is pretty good but not as good as a zc

 

Because a ZC requires an intermediate shaft and new axles. Who wants to buy new axles if you don't have to?

And stock for stock, ZC vs. Si, there is such marginal difference in performance that it's not worth the effort/expense.

 

I bought my DOHC ZC w/ a blown tranny, so i was for the look out of a ZC or Si tranny. I always hear which one is better, but i can say peeps favor the Si. I luv my motors how they came out of the factory, So i picked up a ZC tranny and clutch from HMO for $150 And i luv it, at the street races i smoked another Ef hatch like mine w/ same motor and Si tranny by like 2-3 cars, im serious...

 

the zc tranny is mostly used for racing do to the gearing. it is a more performance then the si tranny. when your cruzing on the high way with the zc tranny your rpms are going to be much high then that of the si tranny. what most people do so you could have the benefits of an si and the zc is to put the zc 1-4th gears with the si 5th and put the si diff so you dont have to buy new axles.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RedRocketCRX &raquo;</TD></TR><TR><TD CLASS="quote">the zc tranny is mostly used for racing do to the gearing. it is a more performance then the si tranny. when your cruzing on the high way with the zc tranny your rpms are going to be much high then that of the si tranny. </TD></TR></TABLE>

Not so....

(ZC)Performance 1-5 gearset + mediocre 3.88 final drive = X acceleration
(Si)Mediocre 1-5 gearset + performance 4.25 final drive = X acceleration

80 mph in 5th, rpms:
3900 rpms(Si)
4000 rpms(zc)

He is right about mixing and matching for the best D-series tranny ever.

 

Your right about mixing the gears for acceleration, but at highway speeds, 70~80, you be at about 4300 rpms. That's the only drawback.

 

That's correct.
The first hybrid I had was the zc 1-5....that 5th buzzed at 4400 at 80mph. 400 rpms higher doesn't seem like a lot but it is...That's why most people opt for the si 5th when building a hybrid.