I have a 88gt convertible. I just bought 2003 gt premimum rims look kinda like cobra r rims. I believe I have to go to sn95 front end. Or can I make the lincoln mark7 rotors work some how?

Where is the best article for the conversion. Do I have to get 94or95 proportioning valve and master cylinder?

Also I have eibach lowering springs will this be a problem at all?

And last what size tires are best on a fox body?

Thanks for any tips and info
Mark

 

I also have an 88 GT conv and am doing the five lug conversion. You will need spindles from a 94 or 95 car as they maintain your current track width. 96 and up spindles are wider and are not ideal. You will need either spacers for the ball joints or buy new ones for a 95 when you install the spindles. I was patient and found a guy parting out a 95 Cobra and I got the spindles, booster, master cylinder and all the disc brakes for $150 (which is rediculously cheap). Junk yards around here wanted $150 just for the spindles. I would definitely upgrade the brakes to 13 inch in the front when you do the conversion and from my research, the larger booster is a must. I bought 17x8 for the front and 17x9 for the rear. Tire size will be 245/40/17 for the front and 275/40/17 for the rear. My next step is sandblasting the parts and getting them powder-coated and upgrading my 8.8 rear end to 31 spline with 9inch end welded in. I figured that would be a good upgrade considering you have to get new axles anyway for the conversion and with the money I saved finding the donor car, I can pay for the upgraded rear end.

 

I don't know if it's the best article but it will sure help.
http://home.comcast.net/~mjbobbitt/mustang/page1.html

 

You need the booster and master cylinder from an SN-95. You'll have to install an adjustable proportioning valve in the line that feeds the rear brakes. In order to run an adjustable valve the stock proportioning valve needs disabled or removed completely. The SN-95 master cylinder has two brake lines coming off of it instead of three. One line should come to a T and feed both front brakes. The other line goes to the adjustable proportioning valve and then to the rear brakes.

 

I'm about to do the swap myself. Just have to clean up my parts and get my rims.

To use those rims you will need the 94-95 spindles. I picked mine up complete with brakes for $50 per side from the junk yard.

You only need the proportioning valve if you do a read disk swap. If you use the ranger axles in the rear and just regular 94/95 breaks you don't need to change any of your fox stuff.

Tire size is not 245/40 should be 245/45 and 275/40 if you want them to be the same height. A 245/40 tire will be 10mm shorter than 275/40.
Oh and also if you don't put in sn95 ball joints you will need a spacer about .330" think 5/8" hole. A lot of people use 3 grade 8 5/8" washers per side.
I cant answer the lowering spring question.