Im throwing zc 2,3 and 4th into my si cable transmission along with all new syncros and bearings and LSD.

I know you can use the vx 3rd as 4th in a hydro trans and I was wondering if the same holds true with the cable trans. I have a vx tranny that i may take apart today to steal the 3rd.

Is the 1.066 4th even worth the extra effort over the zc 1.033?

 

Its a 3.87 mph lower gear than the zc at 8000 rpm. I may as well just do it because i have everything. Can i just get confirmation that it will work with the cable shaft and gears.

 

It will work. I'd worry more about shimming the mainshaft if you haven't done so already.

 

why would I need to shim the mainshaft? I take it that the si mainshaft and the zc mainshaft are different because of second gear. My zc mainshaft is a little effed up from 5th gear overheating


Modified by spun Vtec at 8:42 AM 3/7/2008

 

Mainshaft is just like the diff, it has to be shimmed when changed. If your current shim is too thick, you won't be able to turn the trans by hand even with the case bolts only finger tight.

 

Note taken, the inside of the cases are the same right?
if so the shim from the zc mainshaft will work right?

I'm just not sure I can even use the zc mainshaft. If it happens to have the same number of teeth as the si, would the size of the gear or the cut on it be different?


Modified by spun Vtec at 6:20 PM 3/7/2008

 

Inside of the case is the same, but you can't just use the ZC shim. You have to use the correct shim (whatever it might be). You have to use the ZC gear set, meaning the mainshaft and the countershaft gear.

 

Im not sure I understand you. to run the countershaft i would have to ue the zc final drive and i would never run that fd.

I dont even think ill be running the zc mainshaft because it has damage to it. hardly any difference from the zc 2nd and the si second. (1.76 mph at 8000 rpm with 50/15's)

I would be running the si gearset (mainshaft and the countershaft).

Are you talking about the clearances of the gears on the mainshaft or the clearance of the actual shaft in the case?

 

Gear set. 1/2 gearsets are the mainshaft and the countershaft 1/2 gears. Clearance of the shaft in the case. Gear clearance is not controllable with a shim.

 

Ok I got ya. Do you think I'll run into a problem if I use the si shafts? What is an exeptable clearance?

 

If you use the Si mainshaft, you have to use the Si countershaft gears.

Tolerances are in the Helms.

 

your confusing the hell out of me, maybe im doing the same.

This is my plan:

si mainshaft (si second attached) with zc 3rd, 1.066 vx as 4th, and si 5th.
si countershaft with si second, zc 3rd, 1.066 vx as 4th, and si 5th.
si ring gear

 

refresh ownz

the vx countershaft 3rd gear is 1mm taller than the cable si, zc 4th gear. The mainshaft gear is the same height. I hope that I dont run into clearance issues. I dont think the countershaft even has a shim so i hope im ok.



Modified by spun Vtec at 9:33 PM 3/8/2008

 

IIRC, the mainshaft 3rd gear is slightly taller than 4th gear. I ran into this issue with my mfactory gearset which had me using a cable dx/si/zxi 1.259 3rd gear as my 4th gear.

What happened is that the 3rd gear as 4th ended up cutting into the 4/5 spacer on the mainshaft. It turned out fine though.

I measured it once before and noticed that there was in fact a difference, but I didn't record any of my measurements. Why not machine a little bit off of the vx countershaft gear with an angle grinder?

http://www.youtube.com/watch?v=eBGIQ7ZuuiU

 

Thats my plan. Ill post some pics up with the modifications. Thanks for the input.

 

I used the gear as it was. I didnt want to modify it untill I put it in the trans and
checked the clearances. Everything checked out ok. I took the car out today and put some miles on it with the new 3rd, 4th and LSD. Everything was very smooth. Shifts cleanly. I am glad everything was A-ok!