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Calling anyone who runs 28" slicks

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Old May 23, 2003 | 11:02 PM
  #1  
sideways_Into_3rd's Avatar
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Question Calling anyone who runs 28" slicks

I just need some advice or instructions on how to cut my rear bumper to accomodate 28" slicks !!!

i've never modified a body panel before .. so im clueless on what tool to use .. how to finish it up after cutting it .. i dont wanna just cut it and leave it looking like that obviously !!!

i know quite a few of u have done this !! so lets hear how u did it

thanx
Old May 24, 2003 | 03:55 AM
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aggie .. hook the brotha up with some pics

im still deciding on wether or not i should buy 28" or 27" slicks !
i wanna see some results first .. to see if its worth cutting my bumper up .. and how ghetto it'll look with my street tires back on !
Old May 24, 2003 | 05:50 PM
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Here's a couple of pics of my bumper cover - before and after (towards the bottom of the page)

http://camaroz28.cardomain.com/membe...=199561&page=6

Last edited by speedmiser; May 24, 2003 at 05:53 PM.
Old May 25, 2003 | 06:06 AM
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I didnt take as much off as you think. Take a look at this one again. See the cut line. It's only about an inch out, at the bottom.

http://images.cardomain.com/member_i...61_43_full.jpg


The cut piece in the below pic is just turned a bit, and you're actually looking at part of the inner lip, as well. I suppose 2D is a little limiting at times

http://images.cardomain.com/member_i...61_44_full.jpg

Here's a pic of the finished project. Any less off the cover and it would be rubbing on the big end.

http://images.cardomain.com/member_i...0_155_full.jpg

Didnt mean to confuse anyone - of course you dont need to do the fender well cleareaning I did, if you're going to be running a narrower tire. I was only referring to the pics I had of the bumper cover.

Last edited by speedmiser; May 25, 2003 at 06:12 AM.
Old May 25, 2003 | 02:04 PM
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Nothing too radical - Mild 9.5:1 383 with a healthy dose of juice (on pump gas )

I wanted something I could launch on the street with (on nitrous), and needed very little prep - the 13.5's looked to be the ticket (and all that meat just looks cool too. ) I think I'll go with the 13.5 QTP next time though, since they have an 1" less section width, but retains the same 11" treadwidth.
Old May 25, 2003 | 03:07 PM
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So I wont need race gas for a 250 shot (street car ya know )
Old May 25, 2003 | 08:49 PM
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I just took pix of my 28x11.5 QTPs on 15x10 prostars. If anyone would like to see them email me and Ill send you the pics. I didnt have to trim ANY bit of the back bumper. They dont even touch at speeds of 123mph. Now I did have to cut some out of the inner fenderwell to get them to fit with 7.5in backspacing.

Kyle
Old May 25, 2003 | 09:48 PM
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Originally posted by aggiez28
so you lowered the cr just so you could run a 250 with low grade gas??? dosnt make to much sence imo.

why didnt you build it with a hi cr and run like a 175, you would probably get abotu the same power.

if you want to spray big you need good gas......


brook
I think lower compression is a good alternative for a streetcar on pump gas. The 250 shot on a lower compression motor might not have much higher peak hp than a comparable higher compression motor with a 175 shot, but the overall torque curves should look much better on the lower comp motor with the 250 shot. Mine's been together for 4-1/2 years now (without even having to pull the valve covers), has seen a 300 shot, and has never had an ounce of race gas.

But I suppose "big" is realative to what your doing, though

Shoot me an email or start another thread if you want to discuss it further - we've kinda off got off the subject in this one
Old May 27, 2003 | 02:00 AM
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Cut the piece behind the bumper then massage with a BFH the inside front and any area that needs to be moved in. I fit my 28x13.50's in easily just took a lil work.

The cutting i would use a jig saw and tape if you are going to need to cut.

Steven
Old May 27, 2003 | 07:19 AM
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What kind of backspacing are you guys running with those tires? I dont see how you could get away with a little hammering with 28s with a 7.5in backspacing. I had to do like speedmiser and cut a bit out around that spring to get mine to even begin to fit.

Kyle
Old May 27, 2003 | 06:31 PM
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Arrow Well...

...Unlike you guyz, I had to cut NO body panels on my T/A to get my 28 x 10 x 15 Hoosiers slicks to fit. Mild grinding on the caliper and removal of bump stop to make 7.5" Welds fit.

Of course... I used to be the guy that had no problem with getting a '94 car to shift with a 3200 RPM converter. Now that I went to 4140 RPM, ALL that has changed! No 1-2 shift. Sometimes yaz get lucky and sometimes NOT!
Old May 28, 2003 | 03:38 PM
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Originally posted by ElkyRacer
What kind of backspacing are you guys running with those tires? I dont see how you could get away with a little hammering with 28s with a 7.5in backspacing. I had to do like speedmiser and cut a bit out around that spring to get mine to even begin to fit.

Kyle
Interesting how much different each car seems to be.... just like fitting 315/35's on 17x11's.... some people have problems, others just bolt them on.

I ran the QTP 28x11.5-15's, on 15x10 7.5"BS Weld Pro-Stars with no problems. The inner fenders had been hammered for the 315's and the corner had already been cut off the jounce bumper bracket. Only over about 125MPH did they grow enough to start to contact the metal at the front of the wheel opening, so I moved the axle back about 1/4" and let them "radius" the bumper cover.

I just switched to 28x10.5-15W ET Drags and they were a major problem as far as the rear bumper cover.... about 1" needs to come off. But the inner fender just took a few more whacks with a 3# hammer. I haven't actually run them at the track yet, so it might be worse than it looks.
Old May 28, 2003 | 04:10 PM
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funny u mentioned fitting 315s !!!

i put 315s on my car without ANY modification whatsoever .. and i used to have sportlines on my car (1.8" drop in the back)

no banging, no rolling . nada !! t hey fit like a glove !
Old May 28, 2003 | 04:20 PM
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I didnt have problems with clearance front to back. The back bumper cover is pretty close. I can barley fit my pinky between the tire and the bumper cover. But they do not rub on up to 123mph. There is more space at the front than in the back. My car does have a Moser 9in, but I doubt that would make a diffrence with the offset.

Kyle
Old Jun 3, 2003 | 10:59 PM
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Payam
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