front tires hitting inner fender any thoughts

[Custom 68]

Hey guys and gals I just replaced basically all the parts on the front-end of my 68 Chevy. I added 2.5 drop spindles for disk brakes with stock height variable rate springs and 4 inch drop springs rear. I replaced the shocks with Doeshtec (sp) lowered shocks. The truck is solid and handles great except…on a dip at highway speed the front tires bump-out on the upper bolt for the inner fender. This is quite unnerving. My tires are 275 60 R15 all the way around. I don’t know but can measure the backspacing but I have had these tires on there for 15 years without any problems. My old springs had obviously been heated they were all bent to he!! And shot. Do you think I got some bad springs or maybe weak? I measured from the ground (shop floor) to the fender well on the front it measured 28.5 and rear 31.5 inches I really thought it would be more level than this with the drop I had there is 3 inches difference. What do you all think? My engine is 327 with AC. Oh yea my rubber bumpouts look ok.

Please help
Thanks
Dave

[SCOTI]

What wheel width & back-space do the fronts have? A 275/60 is a pretty big tire for the front when it's lowered, so if the offset isn't ideal I could see it occasionally rubbing when compressed.

[Jeff M.]

I have the same problem. 2-1/2" spindles and 1" springs with a BB and A/C. I removed the bolt that was hitting the tire. I'm also running a 275X60 tire on a 8" wheel. Just rubs a tad on the inner panel when I hit a bump and have extra people in it or am hauling some weight. I plan on going with a 6 or 7" wheel and 70 series tires on the front next time.
Just checked and I'm about 1" lower in the front at 27 1/2".

[XXL]

Originally posted by Custom 68
... I have had these tires on there for 15 years without any problems. {snip} I measured from the ground (shop floor) to the fender well on the front it measured 28.5 and rear 31.5 inches I really thought it would be more level than this with the drop I had there is 3 inches difference.

1) Same tires for 15 years? Yikes!

2a) you should measure from the bottom lip of the wheel instead of the ground floor. Since the wheel is metal and not flexible, possibly under/overinflated rubber, you'll always get a consistent measuring point.

2b) comparing the raw front and rear measurements is a mistake. GM didn't plan for the front and rear wheel openings to be exactly the same size... only to look proportional. Thus, when you compare the front measurement to the rear, it really doesn't show you how much rake is on the truck, except in the context of pre-lowering measurements-- that is, if the original numbers were 32/35 and after you lower it the numbers are 28/32, you know you've added a slight amount of rake (since the new measurements are 1" different front to rear from the older ones).

3) Have you thought about removing your inner fenderwells? This isn't for everybody, and it certainly has its own issues, but you'll free up tire clearance that you never knew existed.

I hope this helps,

Kenneth

[Project1970]

They just don't fit, IMO. Between the offset and the lowering - I had 255/70-15s on my truck when I first lowered it with the ECE disc conversion - there's just not enough room.

I've got 245/60-15s on the front of mine now and they're as big as I can go, I think. No way the 275's I've got on back would fit. They've only rubbed once (which was on a really weird bump - normally it bottoms the crossmember before it rubs with these tires and I've done that three or four times in the 10-15,000 miles I've had it set up like this)

[Custom 68]

Thanks Jeff I guess the front of mine is about right then. What do you guys think about the difference in height?
And yes XXL they were really really good tires Same wheels different tires over the time.
I havent measured the back spacing yet but there is a definite rake to the truck. I think I will leave the inner fenders on I kindof like them.

Thanks again for the comments and help