will either the LT1 or LS1 style rear brakes fit under factory 3rd gen 15” rear wheels? What about the typical drag wheel (draglight, prostar, centerline…)?

 

the LS1 brakes won't fit under either of the 15 inch rims i've tried to mount on them.

One was a drag rim for a third gen.

The other was for a buick Grand National.

I'm assuming backspacing is different between them.

 

Are those GN rims or T-type rims? T-type (aluminum) rims are actually very similar to f-body 15” rims, with the exception that they have about a ½” less backspacing (they stick out that much more). If they don’t fit over the brakes then I doubt that the f-body rims will.

If you mean actual GN rims (chromed steel), I don’t know, since I’ve never dealt with a set, but I know that they’re either exceptionally heavy and I know that they are not the middle of the road (they either have more or less room then a typical rim of that size, I can’t remember which one).

Either way, that is helpful… Where they even close? I keep hearing that they will fit 15’s with a small spacer or trimming the fins, but I’ve never actually tried.

 

neither of these rims were model specific.

both sets were universal lug pattern and had the correct back spacing to run on a stock F body, and a stock GN. I honestly don't know anything about them as they were just borrowed from buddies to try.

The F body rim was the closest. It fit right on. I had all the lug nuts hand tightened before i tried to spin the wheel and realized i had tightened it against the brakes. I'd be willing to be that a spacer or just a trimming of the caliper might allow it to clear. I can check for you around christmas time if i can borrow that rim again.

 

15" rims will not work on LS1 rear brakes. My stock TA mesh wheels (16x8) barely fit over them. Its not about backspacing, unless you use a 2" adapter to kick them out a lot. Its just that the caliper won't fit inside the rim.

 

i did a search on LS1tech..

with LS1 rears, basicly most wheels fit with mild grinding... the bogarts are direct bolt ons (4thgenners love their bogarts... i must admit, i kinda like em too.. LIGHT!)

wheels with a unusually small center, like the GTA wheels have (i know they're 16", but that type of small center wheel is what im reffering to) wont fit... you have to grind too much.

you can easily fit almost all 15s with LT1 rear brakes..

 

my gta wheels fit over my ls1 brakes

 

I have 84 15” z28 rims will lt1 or ls1 brakes fit them.

In the tek article is it the same process changing them over.

https://www.thirdgen.org/newdesign/tech/ls1reardisc.shtml

 

my stock 15" ta wheel fit over my ls1 rear brakes, but was so close that it bound up when I tried to turn it. the lt1 brakes are 0.3" smaller (rotors). i'm not sure about caliper clearance, if you'd like I could mount my 85 ta wheels on my 97 lt1 f-car.

 

Web site for making weld rims fit on ls1 rear brakes.
http://www.freewebs.com/casper9t9/dragwheelinfo.htm