Widen stock wheels
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Widen stock wheels
I really would like to keep the stock 16" IROC wheels, but does anyone know where I can have them widened to accept bigger tires?
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Re: Widen stock wheels
http://www.Weldcraftwheels.com/ is where im sending mine. IM installing a 1LE disc setup in the front some time in the next few weeks. After that i can figure out if im widening the fronts or rears. I might install the rears on the front so im not sure what im doing till thats done.
The 1le front brakes push the wheels out about a 1/4 more. So i might run the rears on the front with a small steel 1/8 stock type spacer. Like they used on the rear of the drum brake cars. so it clears the rotor if need be. Put the fronts on the rear and widen them to 9.5. this will add some of the extra width to the outside.
Anyways once the brakes are done i can play around with the rims to see which one i can widen. fronts or rears. either one will end up on the rear of the car. At 9.5 wide on the rear with a 8 on the front is perfect. so im keeping whatever set goes on the front stock width. I have seen some vettes with the Z51 option running the 16x9.5s with a 255/50/16 tire and it looks good. Squares up the side wall and gives the back rims a fatter look.
The 1le front brakes push the wheels out about a 1/4 more. So i might run the rears on the front with a small steel 1/8 stock type spacer. Like they used on the rear of the drum brake cars. so it clears the rotor if need be. Put the fronts on the rear and widen them to 9.5. this will add some of the extra width to the outside.
Anyways once the brakes are done i can play around with the rims to see which one i can widen. fronts or rears. either one will end up on the rear of the car. At 9.5 wide on the rear with a 8 on the front is perfect. so im keeping whatever set goes on the front stock width. I have seen some vettes with the Z51 option running the 16x9.5s with a 255/50/16 tire and it looks good. Squares up the side wall and gives the back rims a fatter look.
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Re: Widen stock wheels
Thanks for the response, let us know what you decide to do.
Very nice looking ride, by the way....
Very nice looking ride, by the way....
Re: Widen stock wheels
I dabated doing this a few years back but as MikeH stated above with the suggestion of the 255/50-16's, that is the widest tire really made anymore in a low profile series for a 16 inch rim. Just not any better choices to actually fit a wider 16 inch rim for a street tire and I just felt it was not worth everything to just gain 1/2" treadwidth no matter how much wider the rim 'appeared' to be. What I may do someday in the fairly near future next time I need tires is- am am debating just buying two Lookalike 17" rears and keeping the two IROC 16" front wheels I have now up there. Kind of a staggard look- but then having just the rears widened to a 17x10 inch rather than the 17x8 theyy come and got to a 285/40-17 tire that is 26.1 dia and will look in aspect ratio about the same sidewall hight as the front 50 aspect ration that is a 25.7 inch dia tire- I have never seen it done, but I think t just may look great and the tire aspect trick would make them look very comparable fron the side.
This would gain me 1 1/4 inch in both section width and tread width from the 245-50 16 on an 16x8 rim to a 285/40-17 on a 17x10 rim which goes to a 11.3 inch section width from the rear and fits the wheel properly.
http://www.tirerack.com/tires/Spec.j...e1=yes&place=1
This would gain me 1 1/4 inch in both section width and tread width from the 245-50 16 on an 16x8 rim to a 285/40-17 on a 17x10 rim which goes to a 11.3 inch section width from the rear and fits the wheel properly.
http://www.tirerack.com/tires/Spec.j...e1=yes&place=1
Last edited by HPE; Apr 3, 2007 at 12:31 AM.
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Re: Widen stock wheels
Well, I have heard excellent things about Weldcraft Wheels. Next question is to those who have done this..... how wide have you gone and do you have any pictures?
Thanks!
Thanks!
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Re: Widen stock wheels
I don't think many people have done that, widen stock wheels... I want to say JerryWHO did it, but i'm not sure if it was him... try searching?
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Re: Widen stock wheels
Jerry did do this to some IROC factory wheels. He did it hisself in his own 'machine shop' garage so to speak. He cut one set in half (4/4), and he cut the other set in 6/2. He then welded on four inch front to the 2 inch back making the fronts 6 inch wide, and then welded the 6 inch front to the 4 inch back making a 10 inch wide rear rims. he TIG welded them and if you have never seen Jerry's work it is exceptional- He is an ex sprint car racer and fabricator.
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Re: Widen stock wheels
several years ago (at least 15) i had some 1971 Z28 steel wheels widened by someone in northern california and they came out excellent (i still have them). they were 7" stock and they are now 10". they cost 125.00 each back then so i can't imagine what it would cost to do aluminum wheels.
i think 10" wide 16" irocs would look great. if you find someone please post pics/cost/location. thanks
i think 10" wide 16" irocs would look great. if you find someone please post pics/cost/location. thanks
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Re: Widen stock wheels
You are right, that looks good. I actually contacted some folks and one is supposed to call me back from Stockton Wheel. Viking Wheel responded that they could do it for $350 a wheel!!!
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Re: Widen stock wheels
No there after market...but they show what a 255/50/16 tire looks like on a 16x9.5 rim. I like the look... im not into the tall and narrow wheels you see today.
I got the 1LE brakes done and the extra 5/16 more offset is hardly noticable. So im keeping the front rims on the front.
Just have to figure out want rim to use on the back to get the 9.5 rim in the wheel well. Because the way they have to widen them all the extra 1.5 goes towards the inside of the rim. The front are offset to the outside more then the rears. So if i ran fronts on the rear that would put some of the extra width to the outside and the rest to the inside. And the 1LEs push the fronts out 5/16 so this would bring the track width back closer to stock.
I guess its fronts for the rear, i have an extra set. Thats not polished so i will send them out first and have them done. Then polish them up.
will post pics when it done.
I was quoted 150.00 a wheel from weldcraft.
I got the 1LE brakes done and the extra 5/16 more offset is hardly noticable. So im keeping the front rims on the front.
Just have to figure out want rim to use on the back to get the 9.5 rim in the wheel well. Because the way they have to widen them all the extra 1.5 goes towards the inside of the rim. The front are offset to the outside more then the rears. So if i ran fronts on the rear that would put some of the extra width to the outside and the rest to the inside. And the 1LEs push the fronts out 5/16 so this would bring the track width back closer to stock.
I guess its fronts for the rear, i have an extra set. Thats not polished so i will send them out first and have them done. Then polish them up.
will post pics when it done.
I was quoted 150.00 a wheel from weldcraft.
Re: Widen stock wheels
On the 255/50-16, Yes there are some manufacturers that still make that size, but no one makes a good max performance tire in that size. I will still take a max prformance 245/50-16 on an 8inch wheel over an average performance 255/50-16 on a 9-10 inch wheel.
There are NO good street tires in that size.
You can find only one good racing compound tire in a 275/45-16 and even that is only 25.3 inches tall rther than the 25.7-26 inch range found on these cars.
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Re: Widen stock wheels
Thank you for corrcting that, I do recall this now as correct info, and that explains why no search info on IROC and Jerrywho came up.
On the 255/50-16, Yes there are some manufacturers that still make that size, but no one makes a good max performance tire in that size. I will still take a max prformance 245/50-16 on an 8inch wheel over an average performance 255/50-16 on a 9-10 inch wheel.
There are NO good street tires in that size.
You can find only one good racing compound tire in a 275/45-16 and even that is only 25.3 inches tall rther than the 25.7-26 inch range found on these cars.
On the 255/50-16, Yes there are some manufacturers that still make that size, but no one makes a good max performance tire in that size. I will still take a max prformance 245/50-16 on an 8inch wheel over an average performance 255/50-16 on a 9-10 inch wheel.
There are NO good street tires in that size.
You can find only one good racing compound tire in a 275/45-16 and even that is only 25.3 inches tall rther than the 25.7-26 inch range found on these cars.
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Re: Widen stock wheels
Widdened would be a ++ on the coolness factor but Id work on your suspention 1st.
If your makin the power no matter what your not gonna hook on the street.
anyways,
here are a few links I have saved....
http://www.ws6.com/wheels.htm
Jerrys Rims
https://www.thirdgen.org/forums/atta...s-mvc-007f.jpg
https://www.thirdgen.org/forums/atta...s-mvc-011f.jpg
https://www.thirdgen.org/forums/atta...s-mvc-002f.jpg
If your makin the power no matter what your not gonna hook on the street.
anyways,
here are a few links I have saved....
http://www.ws6.com/wheels.htm
Jerrys Rims
https://www.thirdgen.org/forums/atta...s-mvc-007f.jpg
https://www.thirdgen.org/forums/atta...s-mvc-011f.jpg
https://www.thirdgen.org/forums/atta...s-mvc-002f.jpg
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Re: Widen stock wheels
Thank you for corrcting that, I do recall this now as correct info, and that explains why no search info on IROC and Jerrywho came up.
On the 255/50-16, Yes there are some manufacturers that still make that size, but no one makes a good max performance tire in that size. I will still take a max prformance 245/50-16 on an 8inch wheel over an average performance 255/50-16 on a 9-10 inch wheel.
There are NO good street tires in that size.
You can find only one good racing compound tire in a 275/45-16 and even that is only 25.3 inches tall rther than the 25.7-26 inch range found on these cars.
On the 255/50-16, Yes there are some manufacturers that still make that size, but no one makes a good max performance tire in that size. I will still take a max prformance 245/50-16 on an 8inch wheel over an average performance 255/50-16 on a 9-10 inch wheel.
There are NO good street tires in that size.
You can find only one good racing compound tire in a 275/45-16 and even that is only 25.3 inches tall rther than the 25.7-26 inch range found on these cars.
I dont plan on doing any all out racing myself so they fit my needs.
Yes there are more tires offered in the 245/50/16 size. But there will always be a Good street tire in a 255/50/16 for the C4 guys.
Your idea of a 17" rim out back is a good one lots of nice tires in that size.
Last edited by MikeH; Apr 9, 2007 at 10:39 PM.
Re: Widen stock wheels
Please do not take offence to this but I have what is suppose to be BFG's top tire in the 16" line which is the KDW. This tire sucks (Yess I hate them that badly)-they 'feel' as skinny as they 'look', no very reasuring feeling, feels like I have half the tire I had with the GSD3 Goodyears. Also, They look like crap. They are very skinny for a 245/50-16. So if the BFG sport is your choice, they look as skinny as the KDW does with less grip than the KDW and the 255 will still look skinnier than a Goodyear GSD3 in a 245.
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Re: Widen stock wheels
[QUOTE=HPE;3296646]Please do not take offence to this but I have what is suppose to be BFG's top tire in the 16" line which is the KDW. This tire sucks (Yess I hate them that badly)-they 'feel' as skinny as they 'look', no very reasuring feeling, feels like I have half the tire I had with the GSD3 Goodyears. Also, They look like crap. They are very skinny for a 245/50-16. So if the BFG sport is your choice, they look as skinny as the KDW does with less grip than the KDW and the 255 will still look skinnier than a Goodyear GSD3 in a 245.
No offence taken every one has there own opinion.
Ive never tried those, so i cant comment. I have no complaints about the BFG sports though. They stick great in the corners and straight line traction was impressive to me. There quite, and smooth, I like the tread design as well. Not many tires ive had i could say that about. Have to see how they do as they wear more.
Firestone is the worst ive seen. when it comes to a narrow tread width with the same size tire.
Are the goodyear GSD3s still avalible?
No offence taken every one has there own opinion.
Ive never tried those, so i cant comment. I have no complaints about the BFG sports though. They stick great in the corners and straight line traction was impressive to me. There quite, and smooth, I like the tread design as well. Not many tires ive had i could say that about. Have to see how they do as they wear more.
Firestone is the worst ive seen. when it comes to a narrow tread width with the same size tire.
Are the goodyear GSD3s still avalible?
Re: Widen stock wheels
Trust me they are that good of a tire. If nothing better looking comes along between now and about 6 more months when I will be in need of a new set after these crappy KDW's, I will be definately buying another set of the GSD3's.
Yes they are still availiable and tirerack lists the 245/50-16's (25.7" dia and 10" wide on an 8" rim-this is the tire I had n my car pictured above)@ $155 (ps I would still pay more for them- but don't tell Goodyear that). They do not make a 255/50-16. However, as mentioned on the staggered look 17"rear, they do make both a 275/40-17 @ 25.7" dia/10.8" wide and a 285/40-17 @ 26.1" dia and 11.3" wide.
http://www.tirerack.com/tires/Spec.j...e1=yes&place=0
Yes they are still availiable and tirerack lists the 245/50-16's (25.7" dia and 10" wide on an 8" rim-this is the tire I had n my car pictured above)@ $155 (ps I would still pay more for them- but don't tell Goodyear that). They do not make a 255/50-16. However, as mentioned on the staggered look 17"rear, they do make both a 275/40-17 @ 25.7" dia/10.8" wide and a 285/40-17 @ 26.1" dia and 11.3" wide.
http://www.tirerack.com/tires/Spec.j...e1=yes&place=0
Re: Widen stock wheels
This post is no B.S., This pic of it autoxing was on worn 25,000 mile Goodyear GSD3's and the same daily street alignment that had given the tires their 25,000 mile life- Nothing was changed for that day and these tires were so worn I replaced them the next day with the crappy BFG's.
Look had how hard the car is biting and the inside is lifting, Thats not body roll as much as it is traction lift. The body is staying realitively flat in relation to the suspension. You can see how hard the lateral g's are by how much I am leaning my body into the turn in the drivers seat. this car has pulled a 1.07g on a skid pad EXACTLY as you see it here in this picture- ON STREET TIRES- those being 245/50-16 GSD3's.
ps- that back blob directly behind the steering wheel is not my arm on the wheel, its the seat headrest. my head and body is copletely leaned towards the passenger side and my right hand is pulling down on the wheel turn it right below sight. It is hard to even stay in the old seats of this car- I had to end up putting Momo bolstered seats into it just to keep my *** in place.
ps- that back blob directly behind the steering wheel is not my arm on the wheel, its the seat headrest. my head and body is copletely leaned towards the passenger side and my right hand is pulling down on the wheel turn it right below sight. It is hard to even stay in the old seats of this car- I had to end up putting Momo bolstered seats into it just to keep my *** in place.

Last edited by HPE; Apr 9, 2007 at 07:26 PM.
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Re: Widen stock wheels
several years ago (at least 15) i had some 1971 Z28 steel wheels widened by someone in northern california and they came out excellent (i still have them). they were 7" stock and they are now 10". they cost 125.00 each back then so i can't imagine what it would cost to do aluminum wheels.
i think 10" wide 16" irocs would look great. if you find someone please post pics/cost/location. thanks
i think 10" wide 16" irocs would look great. if you find someone please post pics/cost/location. thanks
Odds are you dealt with Stockton Wheel. I have had them make several sets of steel wheels for my cars over the years. For my 67 camaro (which I have a few sets of wheels for) they took some 15 x 7 and make them into 15 x 4 and the rears went from 15 x 7 to 15 x 10 They also had trim rings so that they looked stock. I always get complements when I drive the car that way. Usually I have 15 x 7 up front and 15 x 8 with a custom offset to make it fit realy nice.
The funny thing is they still charge $125 to do a wheel. But it has been a few years since they have done any for me. I do not know if they do aluminum wheels.
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Re: Widen stock wheels
Please do not take offence to this but I have what is suppose to be BFG's top tire in the 16" line which is the KDW. This tire sucks (Yess I hate them that badly)-they 'feel' as skinny as they 'look', no very reasuring feeling, feels like I have half the tire I had with the GSD3 Goodyears. Also, They look like crap. They are very skinny for a 245/50-16. So if the BFG sport is your choice, they look as skinny as the KDW does with less grip than the KDW and the 255 will still look skinnier than a Goodyear GSD3 in a 245.




Do other 245/50's really look that noticably wider, because it's not something I've noticed before. In fact, I always felt like the BFG's looked wider than other brands' tires...
And is your car a V6? It looks like a car I saw a while back on TGO that I fell in love with, LOVED the paint on it... And that one was a V6...
Last edited by InfernalVortex; Apr 10, 2007 at 01:55 AM.
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Re: Widen stock wheels
I just sent my 15" IROC wheels to Weldcraft about a month ago. I have gotten them back but not on tires. I liked the stock wheels and I'm working on polishing them up real good so I don't have them on tires yet. All my wheels are 15X7's so I had 2 of them narrowed to 15X5 and the other two widened to 15X8.5 as that is what MT says for their 275/50 tire. I've got $700 in them including shipping......is it worth it.....I can run a skinnier tire now up front and bigger in the rear, have stock wheels and be different than Prostars or Draglites, so I guess it is, but I'm sure other's would think it's a joke to put that much into it. Yes, they were $150 a wheel and I'm pleased with the look of them. Now just have to get the car done.
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Re: Widen stock wheels
Thanks, I appreciate it. By the way, I am happy you did your rims, it will make it unique from anybody elses!!
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Re: Widen stock wheels
Yeah, that's what I thought. I would be different, run a skinny tire up front (less rotational mass), and still look good. I have just stripped the clear off for now. Hopefully this week and next, I can get them sanded down and polished back up. I would recommend Weldcraft. They have done a lot of wheels for some really nice cars. I had 2 narrowed 2" and 2 widened 1.5", 15X8.5 and 15X5. Here ya go....






Last edited by myz06; Apr 18, 2007 at 09:18 PM.
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Re: Widen stock wheels
hey thats awesome thanks for sharing those! Thats something you dont see everyday. There are alot of really nice billet wheels out there. But i love the resto mod look.
Good to hear your happy with weldcraft i will be sending mine there soon. To have the rears done. So the 15s were 7" wide stock i thought they were 8" didnt know that.
Good to hear your happy with weldcraft i will be sending mine there soon. To have the rears done. So the 15s were 7" wide stock i thought they were 8" didnt know that.
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Re: Widen stock wheels
Thanks!! Yes, I figured they were 8's also until I was looking at the back of them and saw 15X7 marked on them and than I measured to be sure and yep, they were 7's. I guess I really won't know much about them until the car is going so if your's is done before mine, let me know how the car rides. I'm sure they will be fine though.
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Re: Widen stock wheels
Thanks!! Yes, I figured they were 8's also until I was looking at the back of them and saw 15X7 marked on them and than I measured to be sure and yep, they were 7's. I guess I really won't know much about them until the car is going so if your's is done before mine, let me know how the car rides. I'm sure they will be fine though.
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Re: Widen stock wheels
I would say 2-3 weeks depending on how busy they are. I know it's no fun on jackstands......I've been that way since December working on the car
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Re: Widen stock wheels
Huh, the stock 15x7’s should have had a ½” offset, or 4.5” backspacing and 3.5” front spacing. Adding 1-1/2” to the back side while keeping the front side spacing the same is going to result in a wheel with 6” BS, or 1.25” offset, which won’t really work. You’d need to run a .75” thick spacer to put the tire in the same location as with the stock wheel, or something more like 1.25” to get them out where most people run them (I personally think that is too far out anyway). Either way that results in needing a rather thick spacer or having done something else to the car to get it to fit right…
Narrowing the fronts down to 5” should end up with a -.5” offset, which I think will work oK with a narrow enough tire…
Narrowing the fronts down to 5” should end up with a -.5” offset, which I think will work oK with a narrow enough tire…
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Re: Widen stock wheels
Yeah, I knew the backspacing would increase for the rear. Just going to have to put them on and see what it looks like and take it from there. I'm going with a 165 tire up front.
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Re: Widen stock wheels
Huh, the stock 15x7’s should have had a ½” offset, or 4.5” backspacing and 3.5” front spacing. Adding 1-1/2” to the back side while keeping the front side spacing the same is going to result in a wheel with 6” BS, or 1.25” offset, which won’t really work. You’d need to run a .75” thick spacer to put the tire in the same location as with the stock wheel, or something more like 1.25” to get them out where most people run them (I personally think that is too far out anyway). Either way that results in needing a rather thick spacer or having done something else to the car to get it to fit right…
Narrowing the fronts down to 5” should end up with a -.5” offset, which I think will work oK with a narrow enough tire…
Narrowing the fronts down to 5” should end up with a -.5” offset, which I think will work oK with a narrow enough tire…
Joined: Jun 2001
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Re: Widen stock wheels
Rim width is measured from bead to bead, not lip to lip. Backspacing is measured from hub surface to lip. The lips are around ½” thick on an aluminum wheel, so a 7” wheel will measure 8” from lip to lip
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Car: 90 IROC
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Re: Widen stock wheels
Oh i get it, thanks for clearing that up.
Got my rims back tonight they are 16x9.5 IROC rims, and have a 5.75" backspacing and fit perfect. I did have to grind the driver side bump stop bracket some. Only because when you raise or lower the car it rubbed slightly when the rim would pass the bump stop. When its resting and going thru its normal range of travel there was plenty of room.
myz06...i just installed my rims and they balanced out great no problems nice and smooth. Good luck with yours.
Got my rims back tonight they are 16x9.5 IROC rims, and have a 5.75" backspacing and fit perfect. I did have to grind the driver side bump stop bracket some. Only because when you raise or lower the car it rubbed slightly when the rim would pass the bump stop. When its resting and going thru its normal range of travel there was plenty of room.
myz06...i just installed my rims and they balanced out great no problems nice and smooth. Good luck with yours.
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From: Paducah, KY
Car: 87 IROC
Engine: 406
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Axle/Gears: 10 bolt 3.73
Re: Widen stock wheels
Awesome.....yeah, I got mine mounted the other day and they balanced out great. The skinnies look really good and are definitely different. Car is still on jackstands as the rear is out from underneath it, but I'll try to get some pics up. Also, I would like to check out some pics of yours if you have any on the car and what they look like. I think I'm going to like the looks....
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From: Fla
Car: 90 IROC
Engine: 406
Transmission: GMPP 93/4L60
Axle/Gears: 9 bolt 3.27
Re: Widen stock wheels
Yeah post some pics when you get them mounted on the car!
Look for a post i made today about mine on this board there are pics in it.
Look for a post i made today about mine on this board there are pics in it.
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iTrader: (10)
Joined: Jul 1999
Posts: 1,780
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From: Fla
Car: 90 IROC
Engine: 406
Transmission: GMPP 93/4L60
Axle/Gears: 9 bolt 3.27
Re: Widen stock wheels
Mine didnt need much either, no more then usual. They feel smoother then before, might just be a better balance job though.
Re: Widen stock wheels
Just a silly side note. When I first got my IROC rims to put on the car, I installed the valve stems onto them only. I then took them down to a buddies shop and he let me run them on his wheel balancer WITHOUT the tires installed yet and I was able to grind the inside of the rim in various spots inner and outer areas to get the wheels themselves perfectly balanced. THis reduced the overall weights I have had to add to the back insides of the rim to balnce various tire choices over the years. I am generally within 1 once and two of my current wheels have no weights at all added.
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Re: Widen stock wheels
go to summit racing mickey tompkins dot street legal tires 315/45-16 these will fit 10-12" width section.
the backspacing isues yall are having can be solved by adding some of the widening to the outside of the wheel.
the backspacing isues yall are having can be solved by adding some of the widening to the outside of the wheel.
Last edited by MCWOOD2006; Oct 6, 2008 at 06:54 PM. Reason: addition
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