I did and entire T5 swap only to have it die 6 months later. My master slave cylinder wasnt aligned perfectly, it blew the cylinder. I ripped the entire car apart before coming to that conclusion.

It was the Mcloeds Adjustable unit-They sent me a replacement but im not sure if the hole I drilled is accurate.


Every step of the T5 process is pretty simple except where to drill the hole for the master slave. Does anyone have the exsact measurement from a factory car?

This would help me out and maybe anyone else out there.

 

If you don't get anything by next week I'll be headed back to the junkyard to pull some parts off a factory 5 speed third gen. I can get you some measurements then.

 

You should have 2 support bars that come down and land against the firewall. Those will give you your u-bolt mounting drill points. Then you use a 1 3/4 hole saw in the center. You have to elongate the hole towards the top for the master to seat properly. It will end up an oval. I used a rasp for my drill and it worked great. Make sure you hook the master to the clutch pedal before tightening down the u-bolt nuts.
I went through 2 masters before I figured it out.

 

i did that- my hole was off by maybe 1/16 of an inch. which caused the piston inside the slave to rub against the wall-of itself.

There is so much room between those two holes. I want to be exact if I am to do this again. If you look at my other thread it took me 20 hours or more to rip apart and figure out what was wrong with my setup, I wouldn't take another chance.

Thanks V8SC- it would be appreciated if you got that info.

 

Damn man, I hope I got mine right this time. Seems to be. But if it took yours 6 months...... If it breaks again I am going to commit vehicular homicide (to the car).

 

1/16 will make no difference at all. you must be off more than that, or have a defective piece.

I installed the pedals, and made the holes in my 86 where the supports landed, been fine for years, did no crazy measuring.

my t5 swap in my 92 i currently working on uses 4th gen pedals, the support is a lot more flexable than the stock 3rd gen stuff, so i places a straight steel ruler against the side of the clutch pedal, right at the pin and to the firewall and used that as a mark to measure from.

 

^X2.

I blew my first master and slave, but they were used.......bought new and no problems since. FYI Advanced Auto has the nice aluminum slave unit.

I also used the pedals as the template, and cut the hole into an oval from there.

 

i scrapped the entire car because of this. It was indeed the mcloeds master cylinder. And it was off by about 1/16. They sent me a new on but by then I could care less the car had a bent frame and now no trans and a crappy drum rear. Abort.

But I do have my brothers 86 Iroc (he died) That he left me and as soon as my dad takes the keys out of his butthole Id like to drop a t56 in it.

So that being said : IF ANYONE HAS THE EXACT MEASUREMENTS for where the Stock hole is supposed to be drilled: It would be very much appreciated.

As i can see this information would also be useful to anyone else doing the swap. Even though I hear lots of people do this without a specific measurement. My auto Z28 had NO holes of any kind for the MS or pedals or anything.

 

The stock hole is slightly slotted.
Secondly, the bolt holes are what locates it.
Thirdly, McLeod had some issues over the years with their master cylinder.
Fourth, the T5 takes a 3/4" bore master cylinder; try a stock one instead & sell the McLeod.
Fifth the pushrod doesn't have enough angle to **** the master cylinder piston in the bore unless you've really goofed, so don't assume that was the issue that caused the McLeod issues.
Sixth, good luck w/ the new-to-you IROC and sorry about your brother.