First Gen F-body with 9" wide front

[68Formula]

So I'm considering the US Bandit Wheels in 18". Width choices are 8" with 4.5" or 9" with 5.25".

Stock frame, DSE UCA, Guldstrand Mod, Bear Front 13" Brakes.

Right now I have 245/45R17 on an 8" rim with 5" backspacing. It just barely touches the frame at full lock. So, I'm certain that if given the choice, the optimum b.s.for 8" would be 4.75" (which I think many on here would concur).

Hoping to stay with a 245/40 front. I'm concerned the 4.5" back space, may push the tire too far out and cause rubbing. If you compare, the 9" with 5.25" in theory would center the tire the same as a 4.75" on a 8" rim. But I haven't heard anyone mention running a 9" rim up front.

Anyone try this?

[Schwartz Performance]

If you're worried about the exterior clearance, let's talk in terms of front spacing. It's the opposite of back spacing, measured from the mounting surface to the outer lip.

Since wheels are measured from the bead seating surface and not overall width, 8" wide wheels are 9", and 9" are 10" wide.

Your current wheels are 9" overall, -5" BS and you're left with 4" front spacing (FS).
So let's say 4" FS is acceptable since you don't rub.

4.5" BS on a 8" wheel is a 0 offset. Meaning the FS is the same as the BS. (9-4.5 = 4.5).
So the 8" in question have .5" more front spacing, pushing your wheel out just a half inch, and giving you clearance to the inside when turning.

9" wheel is 10" wide. 10-5.25 BS is 4.75" FS. That means the wheel is pushed even further to the outside, but it also has more BS than your current wheel and will rub more.

Hope this helps give you a better visual!

-Dale

[the owl]

I have 18x9's up front with 265's

Backspacking 5.98
Offset +25

I do have slight tire rub on the subframe. Its the tire buldge not the wheel that rubs, I bet if I had 255's it wouldn't rub. I also had to roll fenders and go pretty extreme with the camber to make this work properly so it wouldn't rub the fender lips, again 255's would have helped this as well.

One more piece to mention is brakes..... I am running wilwood spindles and rotors which do move the tires to the outside slightly more.

I can get pictures of my fronts to you if needed.

[68Formula]

I have 18x9's up front with 265's

Backspacking 5.98
Offset +25

I do have slight tire rub on the subframe. Its the tire buldge not the wheel that rubs, I bet if I had 255's it wouldn't rub. I also had to roll fenders and go pretty extreme with the camber to make this work properly so it wouldn't rub the fender lips, again 255's would have helped this as well.

One more piece to mention is brakes..... I am running wilwood spindles and rotors which do move the tires to the outside slightly more.

I can get pictures of my fronts to you if needed.

Good point, I forgot to mention disc brakes (although, this is pro-touring so I figured that was a given. :) ).

Mine rubs on the tire bulge against subframe as well. But again, I have to fully turn the wheel, and then it just barely makes contact. Love to see pics of your setup.

[68Formula]

If you're worried about the exterior clearance, let's talk in terms of front spacing. It's the opposite of back spacing, measured from the mounting surface to the outer lip.

Since wheels are measured from the bead seating surface and not overall width, 8" wide wheels are 9", and 9" are 10" wide.

Your current wheels are 9" overall, -5" BS and you're left with 4" front spacing (FS).
So let's say 4" FS is acceptable since you don't rub.

4.5" BS on a 8" wheel is a 0 offset. Meaning the FS is the same as the BS. (9-4.5 = 4.5).
So the 8" in question have .5" more front spacing, pushing your wheel out just a half inch, and giving you clearance to the inside when turning.

9" wheel is 10" wide. 10-5.25 BS is 4.75" FS. That means the wheel is pushed even further to the outside, but it also has more BS than your current wheel and will rub more.

Hope this helps give you a better visual!

-Dale

Thanks Dale. I completely forgot the advertised width doesn't consider the tire bead.

My big concern is the outside fender lip to tire under compression. On the plus side I have a about -1 degree static camber, and with the Gmod, the tire should move away from the outside fender as the suspension compresses.

[the owl]

Here are some quick pics that I have.... Not front tire specific but you can get an idea. If you want some specific pictures let me know. As far as the tire rubbing I am using a Jeep steering box and ride tech tru turn, so that may be part of it as well, I just fabbed some quick bump stops so it doesn't rub when racing or sliding around in empty parking lots haha. Another thing to mention is I do not have inner fender wells due to my hotside pipes which eliminates a lot of inner rubbing concerns but I can take some pictures of under the hood so you can see there too just let me know.

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[MAGONSTERZ68]

18x9.5 c5 wheels with billet hubcentric spacers at all four corners for a total of 5.5 back spacing, as well as 275x35x18 Dunlop tires and only slight contact at full lock and off camber front and rear. Can't even tell where it contacts tire with the naked eye, only paint scuff on frame show graze. Willwood brakes, rolled lips and lowered 4"s front 3"s rear. Hotchkiss 600lb springs & Uca, Detroit speed lca, tru turn kit. Had toModify upper-outer fender well to accept full wheel travel. No bottoming out and handles extremely well.

[the owl]

18x9.5 c5 wheels with billet hubcentric spacers at all four corners for a total of 5.5 back spacing, as well as 275x35x18 Dunlop tires and only slight contact at full lock and off camber front and rear. Can't even tell where it contacts tire with the naked eye, only paint scuff on frame show graze. Willwood brakes, rolled lips and lowered 4"s front 3"s rear. Hotchkiss 600lb springs & Uca, Detroit speed lca, tru turn kit. Had toModify upper-outer fender well to accept full wheel travel. No bottoming out and handles extremely well.

Do you have any pictures? what size front tire? is this a 69?

[68Formula]

Here are some quick pics that I have.... Not front tire specific but you can get an idea. If you want some specific pictures let me know. As far as the tire rubbing I am using a Jeep steering box and ride tech tru turn, so that may be part of it as well, I just fabbed some quick bump stops so it doesn't rub when racing or sliding around in empty parking lots haha. Another thing to mention is I do not have inner fender wells due to my hotside pipes which eliminates a lot of inner rubbing concerns but I can take some pictures of under the hood so you can see there too just let me know.

126629

That setup looks nice. Are the fronts 35 series? What are the rear sizes?

[Dave95Z28]

[QUOTE=the owl;1186119]Here are some quick pics that I have.... Not front tire specific but you can get an idea. If you want some specific pictures let me know. As far as the tire rubbing I am using a Jeep steering box and ride tech tru turn, so that may be part of it as well, I just fabbed some quick bump stops so it doesn't rub when racing or sliding around in empty parking lots haha. Another thing to mention is I do not have inner fender wells due to my hotside pipes which eliminates a lot of inner rubbing concerns but I can take some pictures of under the hood so you can see there too just let me know.
/QUOTE]

Beautiful car. Off-topic, but would love to see pictures under hood of your car to see your turbo setup.

Dave

[sharp67]

the owl. what are the specifics on your wheel/ tire combo. Wheel mfg, specific sizes, tires, specific sizes, suspension set up front and rear. I like your setup and would like to get this look. info would be greatly appreciated.

Thanks, Jay

[the owl]

Thanks for the complements guys. I will post up a build thread on my car here soon to have all the specifics.

My tires are 265/35/18 front and in that picture I have 315/35/18 drag radials on. The rear wheels are only 10.5 wide so 335's would look a tad goofy. My rear end is narrowed 1" on each side. and its a stock subframe with truturn but speedtech everything else including the chicane kit. I can't say enough great things about speedtech, they have been awesome products, awesome service and great prices in my opinion.

Here are some pictures with 20x11's in the rear for reference. And a quick motor pic for the request, Its nothing crazy as I am not rich and cannot afford the expensive cars so this has been a budget build (at least compared to most PT cars).
I apologize, I am a horrible photographer and only use my phone for pictures haha.

126906126907126908

[MAGONSTERZ68]

68 and have lots of pcs pm me an email.

[MAGONSTERZ68]

Owl,
is car mini tubbed to fit "315/35/18 drag radials with rear wheel width of 10.5 along with 1" narrowed per side rear end" and what is the b.s.?

[HotRod68Camaro]

Magonster, throw them up in the thread. I'm sure a lot of us would like to see it.

[the owl]

Owl,
is car mini tubbed to fit "315/35/18 drag radials with rear wheel width of 10.5 along with 1" narrowed per side rear end" and what is the b.s.?

Yes the car has DSE mini tubs and the backspacing is right around 6.5"

[CliffsBlueCamaro]

I'm really glad someone brought up the discussion of using a 9" wide wheel up front. This is an idea I've been kicking around for a while now. The math definitely seems to work out if you start with 5" of back spacing - which is a tolerable amount for stockish first gen. As Schwartz pointed out, then it becomes a question of front-spacing, which would also land right at 5". That's a lot of front space, but not undoable. Cars with the Tru-Turn and 10" wide wheels use even more than that (5.25") Some mild, unnoticeable modification to the outer section of the wheel well and it should all work.

For me the real question is how much tire to use with the 9" wheel - 245/45/17 with a tiny stretch? 255/40/17 to be squared, or risk it an go all the way with a 265 or 275? The 265's on Owl's car look perfect, but I just wish there were more options in that size.

[MAGONSTERZ68]

I'm really glad someone brought up the discussion of using a 9" wide wheel up front. This is an idea I've been kicking around for a while now. The math definitely seems to work out if you start with 5" of back spacing - which is a tolerable amount for stockish first gen. As Schwartz pointed out, then it becomes a question of front-spacing, which would also land right at 5". That's a lot of front space, but not undoable. Cars with the Tru-Turn and 10" wide wheels use even more than that (5.25") Some mild, unnoticeable modification to the outer section of the wheel well and it should all work.

For me the real question is how much tire to use with the 9" wheel - 245/45/17 with a tiny stretch? 255/40/17 to be squared, or risk it an go all the way with a 265 or 275? The 265's on Owl's car look perfect, but I just wish there were more options in that size.

well if your willing to modify fender wells then why not take full advantage of mod and run 275 35's

[MAGONSTERZ68]

modded fender wells, took the que from the 48hr Camaro and stuffed 275 35 18's at all four corners.127121127122127123127124:

I am the :spam3: King.

these pics were from before I tore it down to as ls2 / trans combo
127125

[Dave95Z28]

modded fender wells, took the que from the 48hr Camaro and stuffed 275 35 18's at all four corners.127121127122127123127124:

I am the :spam3: King.

these pics were from before I tore it down to as ls2 / trans combo
127125

Whose tensioner and ac low mount is that?

[MAGONSTERZ68]

alternator mount is an ls1 vette piece from just bout any one these days and "street and performance" aka "hot rod lane" fixed tensioner and a/c mount designed for single belt operation. Note had to notch and box lower sections of frame to accommodate.

[CliffsBlueCamaro]

well if your willing to modify fender wells then why not take full advantage of mod and run 275 35's

Very good point!

BTW - your car looks killer with those Z06 wheels.

[the owl]

Here is an update with some new wheels/tires with 18x9's up front again.

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[CliffsBlueCamaro]

Very nice! The Welds look awesome. What BS and tire size did you go with up front?

[the owl]

They are 18x9 with 6.1" backsapcing and 265/30/18 up front.

Back is 18x11.5 6.6" backspacing with 335/30/18's