[jocko124]

I first contacted Jon via PM on Lateral-G. Here are the PM's: (6/10/2011-6/11/2011)


Hey Jon,
This is Lee--I have the 66 Cutlass. Quick question on my rear wheels. By giving me the max width wheel that would fit in my rear wheel well you went from a 6" backspace to a 5" backspace and therefore in order for me to be able to lower the rear end of the car I need to shorten the rear end by 1" on each side? I'm asking because I'm going to shorten the rear end and wanted to make sure I remembered your recommendation correctly.
Lee


Lee,
Yes, normally, we would build a 10" wheel with a 6" backspace for a stock length rear end. To make a 5" work, the rear end then would have to be narrowed by 1" on each side.
Does that help?
Jon


Jon,
we've got major problems! I went out to Tim Bruning's shop today and he lowered the rear end all the way with the springs removed and there is approximately 2" of space to the frame from the back side of the wheel and about 3/8" of an inch from the front face of the wheel to the car's fender. I'm not certain if the wheels backspacing was done incorrectly or your calculations were somehow off. I did measure the depth of the dish and it was only 3.75" which makes me think the backspace is 6" and not 5" as we discussed, because I remember you telling me you expected the dish to be about 5". Obviously this is an issue that needs to be corrected and I was wondering what your recommendation is for moving forward?
Lee


Lee,
3/8" is exactly what we want clearance wise to the outer fender. You want the wheel and tire pushed as far as possible out to the outer fender which is achieved by less backspace. If you increase backspace, we'll be essentially tucking the wheel further under the car, and you'll be losing more backspace. So what's the problem again?
Jon


Jon,
The backspace was supposed to be 5"--I believe it's 6". So the wheel fits without narrowing the rear end!
Lee


Lee,
The only way to varify that is to measure them. I'm sure he knows how to measure backspace, but it needs to be measured from the back edge of the rim, down to the mounting surface of the wheel.
Jon


Jon,
Tim measured one of the wheels and the backspace is approximately 5.25". My question to you is, taking into account the fact that there is about 2" of space between the rear of the wheel and the frame of the car, is there a technical reason why you did not build the wheels with a 4" backspace to maximize the depth of the lip as I had requested?
Lee


Lee,
Okay, so they are built right then, with the backspace we asked Forgeline to build them to.
So there are a couple of unanswered questions there then, and I'll lay them all out then for you.
First is there is no way that a 10" wheel would have that much "left over" space between the frame, and your tire. On any stock tub, 66-67 A-body, a 10" wheel with a 6" backspace, and a stock length rear end, would leave you 3/8" to the outer fender, and .75" to the inner fender.
Based on what you are telling me, you are saying you could fit a 11" wide wheel in the back of your car with a 315, and we know that isn't possible on a stock tub.
Also, the rear end under your car can not be a stock length rear end. If it were, your wheel would be sticking an inch outside the fender, and its not, so something may be goofy there. I think the next step would be to verify the length of your rear end.
All I know is these are the facts. A 66-67 A-body takes a 10" wide wheel with a 6" backspace, and at the widest a 285 wide tire. This offset leaves 3/8" to the other fender, and .5-.75" to the inner fender for clearance, which is the max possible. You asked us to narrow that by 1" on each side, and we did so by having the wheels built a 5" backspace, which is what you received. So something else is off here, and we need to figure out what it is... from what you are telling me your car is mini-tubbed with a narrowed rear end already, and unless somebody did some modifications to your car that you didn't know about, there are some missing pieces of information here.
Jon


Jon,
Just talked to Bruning and he does not feel the rear of the car has been mini-tubbed or modified in any way.
Lee


Lee
I'm confused Lee. What do you want me to do for you from here? 3/8" is perfect as far as room to the outer fender. Do you want to widen the wheels?
Jon


Jon,
Actually, I was hoping you would be able to recommend the next step. I relied on your expertise to size a set of wheels for this car. Unless there is some modification to the car (which I am willing to explore further) it appears that you missed the mark based on your assumption that all 66-67 A bodies are similar. The fact that you did not expect the car could be lowered without first narrowing the rear end clearly demonstrates that. I'm not worried about the 3/8" to the outer fender, it's the 2" to the frame that concerns me. So we're back to the initial question I asked you when I purchased the wheels for the car--what's the max width wheel I can fit under the car? If you would like some measurements Tim or I will gladly provide those.
Lee