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-   -   Gen 1 Fender to hub versus ground to pinch weld correlation (https://www.ft86club.com/forums/showthread.php?t=153868)

RedReplicant 08-15-2023 12:34 PM

Gen 1 Fender to hub versus ground to pinch weld correlation
 
Does anyone know how pinch weld height and hub center to fender correlate with respect to the front of the car? I know fenders can vary, as well as how you call measurement points.

Previous owner mangled my front pinch welds (folded over and smashed the floor up) so I can't use them as a measurement point. Rear pinch welds are fine.

As an example:

Rear => 13.2" hub center to fender, 22.5" bottom of a 17" wheel, 5.125" / 130mm pinch weld to ground.

I'm more or less trying to figure out what hub center to fender looks like for the ballpark of 120 – 135mm front pinch weld to ground on a Gen 1 with a 255/40/17 tire on a 17" wheel.

I get that this is fuzzy math, trying to be in the ballpark. Looks like I got it way wrong with 21 7/8 bottom of 17 to fender on my car.

strat61caster 08-15-2023 02:51 PM

From bottom of pinch weld to top of fender I have ~20.25”-20.4”, my right front fender got dinged and thus sits about an eighth inch higher then the rest. Never wrote down hub center to fender as I can back it out with the info I have, and it’s annoying to measure accurately and with uneven fenders not really all that useful.

So if I have 5” at the pinch weld bottom edge, I’ll have ~25.25” at fender arch, which 24.7 wheel diameter means 13.05” from hub center to fender arch.

This of course depends on how you measure your fender arch whether it’s from the bottom of the rolled portion or from the flat face which is another plus or minus an eighth inch.

fwiw I’m 4.8” from bottom of pinch welds to ground, no rake, ~25” from fender to ground and thus ~12.7” from hub center to fender. That’s a 122mm ride height at the bottom of the pinch welds.

Also, you’re not going to see a huge difference moving your punch weld measurement points back or forward a few inches, if it’s still intact by the wheels or near the door jams that should work just fine.

RedReplicant 08-15-2023 03:40 PM

Thank you, I appreciate it. They're mangled back to the doors, unfortunately.

I came up with 21.875" front and 22.75" in the rear measuring from bottom of 17" to fender. Front wheel measures 475mm lip to lip, so that gives me 12.5" hub to fender.

Rear I got 5.125" / 130mm to the intact pinch, so that works out.

Sounds like I got the front way too low, makes more sense now.

RedReplicant 08-15-2023 06:25 PM

Actually, one more question, how much difference is there in wheel to fender arch or hub center to fender arch versus to pinch weld for front versus rear?

As in, how much lower does the rear fender sit than the front given the same ride height.

strat61caster 08-15-2023 10:17 PM

I have same front to back in my notes. Oem ride heights were a quarter inch higher in the rear iirc.

Kelse92 08-15-2023 11:41 PM

I don’t have the differences, but I’ll add input that it’s easier to go off the fenders than the pinch welds for consistency’s sake. They have some variance, but if you compare them to thread distance from the perch on your shock bodies and corner weights you’re probably looking at closer accuracy within mom’s than pinch welds that are constantly getting beat up by jacks, curbs, etc.
I think I have some old notes somewhere I can PM to get you in the ballpark from hub-center to fender but they are in mm.

RedReplicant 08-16-2023 11:39 AM

Quote:

Originally Posted by strat61caster (Post 3589922)
I have same front to back in my notes. Oem ride heights were a quarter inch higher in the rear iirc.

Interesting, thank you much.

Quote:

Originally Posted by Kelse92 (Post 3589927)
I don’t have the differences, but I’ll add input that it’s easier to go off the fenders than the pinch welds for consistency’s sake. They have some variance, but if you compare them to thread distance from the perch on your shock bodies and corner weights you’re probably looking at closer accuracy within mom’s than pinch welds that are constantly getting beat up by jacks, curbs, etc.
I think I have some old notes somewhere I can PM to get you in the ballpark from hub-center to fender but they are in mm.

Thanks, I appreciate it, metric works easier for me anyway. Too many little marks on the tape measure with standard, lol.


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