Wilwood brake master cylinder
 

Iam looking at getting the wilwood brake master cylinder for my 78 vette with power brakes using hydrobooster and wilwood big brake kit, 6 piston calipers etc

which wilwood master cylinder do i get? and is a simple bolt on job?, do the brake lines screw straight in??

cheers

dave

Dave, you'll want the large bore 1&1/8" for power brakes. fitting location is different at master, I think the ports are farther apart. Terry

As I recall. The fittings are different . I think one is the same but one is different. The Wilwood has both fitting the same where OEM has 2 different size fittings.

Gordon is correct but the M/C comes with adapters. I put this on last year. It was bolt on and works great so far. For Hydroboost, I think you'll have to use the internal length adapter because the pushrod for HB is short. Iirc, that adapter was part of the kit that I got from Summit.

Another point to note is that if you use a Motive brake bleeder, you'll need to get the larger adapter plate as the standard C3 one is too short.

Thanks guys for info, sent wilwood a email, see what they can do for me

cheers

:iagree: I have the 1-1/8" Wilwood master cylinder in my 77 with the Wilwood D8-4 calipers and EBC rotors and it all works great.

The D8-6 front calipers were not available when I bought my system.

The master cylinder bolted right in with the stock brake line fittings, no adjustments necessary.

I don't have hydroboost, but so far I don't think I need it as the car stops great.

My car is only street driven, so the hydroboost might be a good addition if you race the car and or you don't have enough engine vacuum for the power brake booster.

Hope that info. helps. :canadaflag::thumbs::cheers::flag:

Did you make it to any fun races this summer?

A bit of a "spoon fed" question but does anyone have a list of suggested suppliers for the wilwood D8-6 & 4's?

Summit racing - big parts house.

I purchased my D8-4 calipers from Corvette Central (the D8-6 was not available yet). Apparently Vansteel also carries all the Wilwood brake kits for our cars as well.

There I have done my part by promoting supporting vendors on the forum. :canadaflag::thumbs::cheers::flag:

cheers, I got an IOU for wilwood brakes last xmas, I better get my backside into gear and order them.

I know this is necro'ing, but when you put your MC in donyue, did you have any issue with the cylinder rod being to long?

I am installing a wilwood mc right now and have noticed what you are describing. With the aluminum insert that converts it from a deep bore to shallow bore, the difference in depth is 1/8 inch. So just to bolt the master cylinder down there is a bit over a 1/8 inch of preload (the cast iron one i took off would still wobble when push against the booster so there was already a small amount of preload).

I see another thread where someone noticed this with a wilwood and mentioned concerns with preload https://www.corvetteforum.com/forums...-push-rod.html

another websites instructions warning of improperly adjusted preload http://www.classicperform.com/Instru...PDF/Master.pdf

another thread mentioning preload but not specifically about wilwood https://www.corvetteforum.com/forums...djustment.html

So far some thoughts on a solution is to trim the small rod that is coming from the booster, on my 1980 it looks like you could trim the flat part that goes into the booster and it should not effect anything, That end has a machined stepped but I checked in the plastic piece it inserts into and did not find a matching step so it should be ok.

Another thought is to find or make a spacer for the master cylinder.
https://cimg7.ibsrv.net/gimg/www.cor...761d7e2550.png


I also have seen in diagrams that there is possibly a spacer that goes between the master and booster originally? The spacer in the first picture looks like it could also make it so the original master has no preload which I mentioned earlier that I noticed a slight amount with the old cast iron master. https://www.corvetteforum.com/forums...al-1970-a.html
https://cimg2.ibsrv.net/gimg/www.cor...0ddfc02dbb.jpg


That first picture shows a part that looks a lot like what you see when you google "master cylinder pushrod spacer" and I wonder if you could use a thicker spacer of that style but Im concerned that if the gap between the master flange and booster is too large and you go to tighten it down you could snap off the master cylinder mounting holes so you would want to put spacers on the booster studs too.

https://cimg0.ibsrv.net/gimg/www.cor...a8968560c5.png

Great video, I ran across that earlier and that looks like a really useful tool, wish I had one

I ended up grinding the pin that goes into the booster since the 80 does not have the adjustable rod. Just trimmed a small amount at a time from the flat end and kept going until the master just barely rocked back and forth when pushed against the booster

https://cimg5.ibsrv.net/gimg/www.cor...0a2c9b7c77.png