My new new 15x10's are here!!! [Archive]

70 gsconvt

03-15-2003, 04:42 AM

OK, I got another new 15x10's with 5-5/8" (now I can shim up to a 1/4" if I need to) backspacing from Specialty Wheel. While they wouldn't take the others back, they were VERY quick to make me another pair and get them out to me. But I did get the other set sold at a little bit of a loss. Oh well, live and learn.

Anyway, I just thought I'd ask, does anyone want me to make measurements of one of the rims on the car before I put the tire on it so anyone can put a rim on their car to measure so as to determine what will exactly fit on their car?

I'd just mount one tire and make all the measurements and then put the rim on and do the same. Let me know. I'll probably get the tires put on Monday and do all the measuring by Friday.

Phil

NOTNSS

03-15-2003, 10:30 AM

Phil,

I'd like to know for sure the exact backspacing required and IF a 10" wheel will clear on a stock '70 GS. I'm looking at Hoosier 27" x 11.5" (10" tread width) for race only and would prefer the 10" wide version. They recommend from 8-10" wheel but I have to think the 10" would work best if it will fit correctly. Isn't 4.75" the stock backspacing? Wouldn't that remain the same regardless of the wheel width? Forgive my ignorance.

11SecondGS

03-15-2003, 11:03 AM

WOW...I wanted to get a 6" backspacing for my AUTODRAGS but at the time they only offered 4 7/8. I did exact measureing with my 10X15 rim with 26.5 X 11 Quicktime pros on my ford/gm mount housing, and I believe I could have gone all the way with a 7" backspacing, fitting an even wider tire size in there. The key to my GS and being able to say I can have such a huge backspacing was the small tire diameter of 26.5 tire height. You couldnt even think about it with 29.5". And as some of the guys say, after the first 100 feet of track, those extra tall tires just become dead reciprocating weight anyway.

I had to molest by inner wheel lip housing chrome trim, but you can't tell unless your look up at from inside the wheel well, which is impossible when the car is on the ground becuase the tire fills up the who damn thing.

I used a sawzall to cut an inch or so off of the trim that was inside the wheel well, and then used a grinder to get it real smoth. The problem was before I did that, the chrome trim was digging into the sidewall of my tire when suspension flexed.

Maybe I should get some pictures.

70 gsconvt

03-15-2003, 11:19 AM

I already have the 325/50R15 DragRadials mounted on the 15x10's with 5" backspacing and they do fit under there with no modifications.

It's just that I have 1-1/8" space on the inside and only 1/8" clearance on the outside by the fender well lip. That's why I'm going with the 5-5/8" backspacing. I should be able to get them dead-nuts centered.

My tires have a 10.4" tread and a 12.9 section width and are 28" tall. I don't think you could get any taller of a tire in there with that kind of tire width.

Like I said, I'll get them on this week and let everyone know and take some pics.

Phil

lcac_man

03-15-2003, 11:59 AM

Phil,
I'm definately watching your progress, while I'll likely be going with 16 or 17" wheels, the backspacing, wheel width, section width and height of the tires will all be the same.
Based on the measurements I've taken on my car 5 5/8" does seem to be the perfect center of the well, now its a matter of determining just how wide and how tall I can go.
I'll be installing air bags to accomadate for load changes so I can push the envelope a bit.
Good Luck

Rodster

03-15-2003, 01:58 PM

Phil-your perseverance is paying off.Thank you for keeping us so well informed of your progress.I want to go with the same rear tire size as you with the 10 inch wheel as well.Likely I could have used the 5 inch backspacing as I cut my rear wheel lip moldings to the "screw line"back a couple of years ago.With 275/60x15 I have approx. 1.6 to 1.7 inches clearance between the wheel lip and the tire(on factory 15 inch rims).I also use air bags as 28 inch tires will just rub the top of the wheel well on rather severe bumps.I was wondering what you have done re front wheels and tires.I think I will stick with 235/60x15 but on an 8 inch rim with 4 inch backspacing.Did you get your rims from Specialty Wheels or Stockton Wheels?I found Stockton on the web.Do you have any contact info for Specialty if that was your source? Our Buicks definitely need all the wheel and tire (rear) that will fit in there for the obvious traction reasons.Looks too are important with the rear end "bustle" these cars have.275s' look downright puny on the 70-72's where they look rather substantial on other vehicles.Again thanks for your efforts.Rod

70 gsconvt

03-15-2003, 02:11 PM

My original post is in error. Wheels came from Specialty Wheel. Stockton didn't want to make them and Wheel vintiques said it could take weeks to months before they could make any as they had no good cores and WILL NOT use a customer's wheels as cores.
Specialty wheel had the cores in stock and made mine and shipped them in about 3 days.......both times:Dou:

I can't say enough good things about Specialty Wheel.

My tires up front are factory 15x7 rims with 245/60R15 BF Goodrich radial t/a's. Front was lowered about 1" so top of tire is right at fender well lip. I had 275/60R15 Dragradials on, but got greedy for a bigger tire. I have a 1-1/4" sway bar on the front and the passenger side does just touch it and rub when fully turned to the left. Oh well, no real fast left handers.

I never had a problem with the rear tires hitting the fender wells at all. The 275's were on 15x8 rims with 4-1/2" backspacing. Maybe I just didn't hit a big enough bump. I have brand new springs at all four corners and polygraphite bushings everywhere. One inch sway bar out back. I also am using Edlebrock IAS shocks all around, so that is probably helping in the bouncing department as they really keep the car flat in the curves. I've chased a few Mustangs and Camaros onto on-ramps and never did they pull away from me.

I am also thinking about "trimming" my fender wells for added insurance. Maybe a 1/4" or so as I don't want to get too close to the screws holding the trim or the welds that hold the inner/outer fender together. They are tack welded, right?

Anyway, I'll get to it probably Wednesday. Everyone keep their fingers crossed.

Phil

Rodster

03-15-2003, 02:55 PM

Phil-Re the rear wheel wells:I had the body shop,in anticipation of my later grinding on the wheel lips, weld the inner and outer pieces close to the outside of the lips.To be honest I only once had the tires rub the top of the wheel wells and that was on a miserable secondary road which was a shortcut to a car show.I later installed air bags for traction reasons but find of course with 4 or 5 pounds of air in them they raise the rear to cover any road problems.I too find the Buick to handle flat through the turns with all poly bushings,good bars front and back,good shocks and in my case an AGR fast ratio steering box with their reduced assist pump.Do you have any contact info for Specialty Wheel?Thanks Rod

70 gsconvt

03-15-2003, 03:50 PM

Here you go:

Specialty Wheels Ltd.:

http://yp.yahoo.com/py/ypResults.py?stx=specialty+wheels+ltd.&stp=a&tab=B2C&city=Portland&state=OR&country=us&msa=6440&slt=45.523830&sln=-122.675346&cs=4

Don't have a specific person to talk to, they're all nice.

Phil

RED GS 1

03-15-2003, 07:59 PM

OK everybody, let me get in on this.
I just got back Today from John Csordas shop upstate N.Y. I've been trying to get up there for 2 mos. but weather stopped me. After trying to fit 29" tires [Hoosier Quick Time Pro's] on Brand new centerline Auto Drag wheels with 4 7/8's backspacing it was a no-go we even trimmed the wheelwells and they still would not work without some serious rubbing! WRONG backspacing,I bought some new Warrior centerlines with 5" backspacing and new 28' tall Hoosier Quick Time Pro's. Both set's of wheels were 10" wide. Now they fit perfect there might even be room for a little more backspacing,maybe 1/4" before the inner side of the wheel gets close to the first obstruction[lower shock mount] all in all it is a perfect fit.
I went from a 8" wide centerline auto drag with M&H's 275x60 to a 10" wide centerline Warrior [both liteweight aluminum] with Hoosier 28x11.5-15LT.
I've always relied on M&H's.This is my first time trying a different tire.Keep in mind I run these on the street, I'm always trying to HOOK better. Time will tell, I can tell you the Hoosiers side by side with the M&H's although basicaly the same size are a 3/8" taller and laying on the side,are 1" wider,same tread width[10"].
I figure if nothing else,the 10" rim will give a bigger foot print and some more traction,which was the whole reason for this in the first place,I hope this helps some of you guys out. I know the frustration of buying the wrong parts I was lucky that Summit took it all back with no question asked,wheels that were mounted Hoosier tires that were removed of thier big white paint and lugnuts that were opened and used! I quess I lucked out on that one,but it did cost me $85 to send it all back,you gotta love that.:laugh:

NOTNSS

03-16-2003, 12:37 AM

Kenny,

Let me see if I can get this straight..:Do No:

I should be able to run a 10" wheel (Convo-Pro for instance) as long as the backspacing is 5"?

I'll probably be using Hoosier QT Pro 27 x 11.5-15LT (27" OD and 10" tread) or
MT ET Streets in 28 x 11.5-15 w/27.3" OD and 8.6" tread.

I will not cut the wheelwell so want to get it right.

Thanks.

70 gsconvt

03-16-2003, 01:50 AM

My first set of 15x10's had 5" backspacing and it was NOT enough. I had to reorder a set with 5-5/8" backspacing to make it all work. I'll find out for sure this week. My tires have a 10.4" tread and 12.9" section width.

Tires/wheels did fit under wheel well, but with only 1/8" clearance on the fender well lip. Who knows, maybe each car is a little differemt.

Phil

RED GS 1

03-16-2003, 06:29 AM

I think one thing that might make a difference is what type rear end is on the car.
I've got a 10 bolt on my GS im told these might be different in length size,compared to a 12bolt.
With Hoosiers Quick Time Pro's,28x11.5-15 on a 10" Centerline Warrior wheel,with 5" backspacing,when mounted section widrh is 12.5". When mounted on the car the closest interference is on the innerside of car by the bottom shock mount I'd say about 3/8 of an inch.Plenty of room on the outside fender lip HAS been cut and rolled due to earlier attempts to make a bigger tire fit.
The cut and rolled lip is invisable to the eye unless you lay on your back on the ground and look up under the fender well. I'll be out today breking in these tires,I don't expect any problems I just hope thier stickie enough!!:Brow:

RED GS 1

03-17-2003, 05:25 AM

Ok, I got the new wheels and tires on today and took pictures.
I'm still new at this so they might be a little blurry.Some pic's you can see the labels still on the tires;the first one shows the difference in a 275x15 radial compared to the new 28x11.5-15 Hoosier on a 10" rim

RED GS 1

03-17-2003, 05:26 AM

and another on the ground

RED GS 1

03-17-2003, 05:27 AM

another

RED GS 1

03-17-2003, 05:28 AM

RED GS 1

03-17-2003, 05:29 AM

still another

RED GS 1

03-17-2003, 05:29 AM

1 more

RED GS 1

03-17-2003, 05:30 AM

last one

RED GS 1

03-17-2003, 05:43 AM

I took it out to a local industial area to "practice" hole shots,I can still burn them up for about 100 Ft. From a standstill if a mash the pedal,I've got a 3500 stall,continental converter with 373 gears.I lowered the tire pressure to 18 LBS. and they were about the same.I did try heating them up first,and this really seemed to help,compared to my old M&H's on 8" rims I think these get me going quicker with some spinning but the car is deffinately moving quicker with the slipping tires.All in All I think this combo is the ultimate for me.I couldnt get a bigger tire in there without mini tubbing it.So in conclusion I give a BIG:TU: to the Hoosier quick time pro's a very intimadating lookin tire with great traction when
run low pressure and heat em up before you launch:Smarty::Brow: :Brow:

NOTNSS

03-17-2003, 09:55 AM

Kenny,

What color is that? Looks like orange in the pictures.

70 gsconvt

03-17-2003, 04:13 PM

WOW:eek2: !! That looks sweet. The 325 DragRadials have a 12.9" section width. We'll see what happens in a few days here.

RED GS 1

03-17-2003, 06:20 PM

Gary.Like I said I'm new to this digital camera and postin pictures the color is off ,it's Fire Red.

RED GS 1

03-17-2003, 06:22 PM

Hey Phil,
I'm anxious to see how you make out.Will you be able to post some Picture?:Do No:

RED GS 1

03-17-2003, 06:28 PM

Oh yeah Phil,one more thing the 28x11.5-15LT Hoosiers claim a section width of 11.5 inches and recommend a 8-10" wheel.Mine are on a 10" wheel and when I laid the tire on its side with a straight edge across the widest part it measured 12.5 inches:Smarty:
I'm pullin for you,and I hope you have Good Luck:TU:

70 gsconvt

03-18-2003, 03:02 AM

Yes, Lon Bauer will be bringing his digital camera over. We'll turn the car into the sun so we can get some good shots of the car/wheels. I'll also see if I can get some pics of the inner and outer clearances.

RED GS 1

03-18-2003, 04:56 AM

Here's a couple more shots I hope you can see the clearence better

RED GS 1

03-18-2003, 04:57 AM

Laying on the ground lookin up into wheel well

RED GS 1

03-18-2003, 04:58 AM

one more

lcac_man

03-18-2003, 08:19 PM

I did a bunch of measuring on my car today to be sure of what would fit, (I'm sure the 70-72's are different), my stock rallyes have 4 3/8" back spacing, and my tires (225-70-15 bfg t/a) have a 9" section width and are 27.4" tall. With them installed I have 2.25" of clearance on the inside and 2" on the outside (lip is trimmed 3/8"). So my plan is to move to a wheel with 6 1/8" of backspace and step up to a tire that has a 12" section width and 27.6" tall (295-50-16) lower shock mount will not interfere with a 16 inch wheel. I measured it three times so there shouldn't be any surprises :shock: .

70 gsconvt

03-19-2003, 06:46 AM

OK!!!!!!!!! Got these bad boys on. :grin: :grin: :grin:

For those who haven't been following, wheels are 15x10 with 5-5/8" backspacing Buick rallyes from Stockton Wheel Ltd. 325/50R15 DragRadials with 30 lbs. pressure.

I have 1/2" clearance on the inside and 7/16" on the fender well. I won't be shimming them out at all. There was only about 5/16" clearance to the shock bolt washer, so I'll grind that back to get another 1/8". Clearance to my exhaust, 2/1-2" mandrel bent, was 5/8".

I will trim my fender wells back up to the, but not including, the screws for added clearance. That will give me a solid 3/4" clearance and absolutely worries about them hitting if I go over a big bump.

Oh, my tires section width measured to just over 13-1/8", measured lying on the ground and using a straight edge. Slightly wider than advertised of 12.9".

So c'mon guys, go get those monster wheels and tires. They'll fit, you just need a little BFH.

Lon is coming over Friday or Saturday. We'll take some pics and he'll post them here over the weekend. Good luck guys.

RED GS 1

03-19-2003, 07:56 AM

I can't wait to see the pictures Phil.:laugh:
I'm glad everything worked out for you after all. I think we both went through the same hassles but the end results were worth it eh?:grin: :grin: :TU: Now,get out there and do some experimenting with your launch ie.HOLE SHOT:beer

70 gsconvt

03-19-2003, 08:14 AM

Oh yeah, forgot to mention this little tid bit. New wheels weigh 61.5 lbs with the tires compared to my 15x8.5 Centerlines with ET Drags 26x10x15 with tubes, which weigh 38.5 lbs.

That's 23 lbs. per side. If you could get similar results up front, that would be a weight savings of 92 lbs. There's another .1 off the ET.

70 gsconvt

03-19-2003, 04:18 PM

Took 'er out for a little ride. No rubbing problems at all. I definitely am glad I did that little "trimming". The tires are totally inside the fender well. No chance of them rubbing at all.

RED GS 1

03-19-2003, 04:42 PM

Wait a minute Phil, you have the Buick rally wheels,Right? they are heavier than any centerlines I know of,you added weight, not reduced, Am I reading this right? I know when I run stock wheels [Ralleys] and change em over I'm always amazed how much heavier they are compared to my alum.wheels. Did I miss something here?
Glad you got out and about with the new set up. How is the hook up? Traction? Holeshot? after all you did'nt go thru all this for nothin:TU:

70 gsconvt

03-19-2003, 04:51 PM

You didn't miss anything. New 15x10 rallye wheels with DragRadials weight 61.5 lbs. My Centerline's with slicks weigh 38.5 lbs.

I got the 15x10's purely for looks. I like having a couple of steam rollers in the back of the car. And I like the way the DragRadials look from behind. I use the Centerlines when I go to the track two or three times a year for fun.

Hopefully it will be a fun time at Norwalk.......lower elapsed times and nothing breaking.

Phil

RED GS 1

03-19-2003, 05:45 PM

OK now I get it. Good job I'm glad it all worked out! I have more fun locally,I only get to the track 1 or 2 times a year,but I'm out every weekend locally,so that's my top priority,beatin down the local brand Xers I'm doin my part for the Buick camp believe me, it is very interesting around here,it is a major street scene, I try to be low key but when your the only Buick GS on the ave. you stick out. Oh yeah some of the other guys cruise by,and they know who they are.I'm the only guy keepin it real if, you know what I mean?:laugh: :laugh:

RED GS 1

03-22-2003, 06:16 AM

Phil, Did you get any Pictures of your new wheel combo yet?:Do No:

70 gsconvt

03-22-2003, 08:53 AM

Lon's coming over today after lunch. He should have them posted by this evening.

I'm going to the Bahamas for a week, so you won't be hearing from me here until April 1. See 'ya.

Phil

70 gsconvt

03-22-2003, 12:45 PM

OK ladies, here they are:

70 gsconvt

03-22-2003, 12:46 PM

And another: (that's Glen Stringfield on the left and me back there)

70 gsconvt

03-22-2003, 12:47 PM

And let's not forget:

70 gsconvt

03-22-2003, 12:48 PM

One more:

TXGS

03-22-2003, 03:46 PM

Very nice!:TU:

RED GS 1

03-22-2003, 04:17 PM

Great job Phil
She really looks MEATY,don't you love the look?
It really adds an Attitude. I think its like pumpin up Barney Fife to Arnold Shwartzineger!!! :TU:

Rodster

03-22-2003, 04:24 PM

Well worth the effort Phil.Can hardly wait to do it myself.Rod

RED GS 1

03-22-2003, 04:26 PM

One more thing while we're on the subject, Phil your 70' is a convertable,I know they made the frames for convertables different than the hard tops maybe this has something to do with the amount of backspacing you required,I'm almost positive anything more than 5 1/4" would have caused me problems.
Anyone have any thoughts on this?:Do No:

70 gsconvt

03-22-2003, 04:49 PM

I just noticed my license plate is crooked. It must be from all the torque when I take off from a light.........................

I wish it was sunnier out. The pictures are kind of dark. 40 degrees and heavy clouds. AAHHHHHH, spring time in Cleveland!!

lcac_man

03-26-2003, 04:10 PM

Phil,
Thanks for all the info on the rears, can you tell me what size fronts your running and what the wheel backspace is on them?

Chris Lott

03-26-2003, 04:18 PM

Wow Phillip, that looks great!!! I really like the look it gives and the stance, very nice.:TU:

SP4SPD

03-27-2003, 09:22 AM

Hey Phil
The 15x10 set up looks great! Im looking forward to seeing it in person at Norwalk. Going to the dyno tomorrow to run my engine.I can hardly wait to see what kind of numbers we post with it! We will have to make a run at Norwalk!

70 gsconvt

03-28-2003, 08:53 AM

Hi, fronts are factory 15x7's, I think backspacing on them is 3 and 1/2 inches. Tires are 245/60R15 BFGoodrich Radial T/A's. Front is lowered about 1 inch and I still have no rubbing problems except passenger side will just touch the 1 and 1/4 inch sway bar at full lock left turn.

pwm72

04-01-2003, 05:57 AM

Hey Phil, I read that you did some mods to your rear wheelwells, but did you do anything to the fronts? I have 3.5" BS on my new Cragars (15x7) and wanted to put on some 235/70/15 (28" tall) BFG's on the front. This is on my 72 convertible. I was concerned that the BS may not be enough...should I be OK?
Thanks

Paul

DEL

04-05-2003, 12:49 AM

This is a great thread you guys! Thanks for all the info. You saved me a lot of pain and concern...once you hang up the phone with Summit or Jegs...all you can do is worry until you see if the stuff fits!

Any idea what your backing plate to backing plate measurements are? I have a 12 bolt Posi, just wondering if I will be able to go the same route. I have some Hoosier 28 X 11.5's and I am going to get some 15X10 Warriors.

70 gsconvt

04-05-2003, 04:51 AM

I'll try and climb underneath today and verify, but it should be 55" from back plate to backing plate. I'll also measure the frame, inside and outside measurements so someone can compare to a coupe.

Phil

tdacton

04-05-2003, 10:47 AM

Phil,
I will be watching for your measurements. I would love to do what you have done to my hardtop car. But, I would rather not go into the hole figuring things out like you have had to. Thanks for the help. Enjoy this cold air while you are out measuring.
Thanks!
Troy

70 gsconvt

04-05-2003, 01:52 PM

Geezzz oh man, it's 30 degrees outside again.

OK, here's the measurements. The rearend is 55" backing plate to backing plate. Corporate 8.5 rear.

Frame that is in wheel wells is boxed and is 40-3/8" on the inside. The outside, once it leaves the wheel wells waves in and out all over the place. It is boxed all the way to the front (on an angle under the passenger compartment) and going to the rear until half way past the gas tank, then it is open on the inside.

Hope this helps everyone.

Phil

DEL

04-06-2003, 10:16 PM

Phillip,

Thanks for the info! This thread is just what I needed! My 70 Skylark should be rolling on 10" of rubber soon! :)

70 gsconvt

05-12-2003, 12:57 PM

Just wanted to update everyone on this thread.

After driving around with these things for a month or so, I have had to install air bags to keep the rear end from bouncing so much on BIG bumps and going around curves REAL fast.

The tires were lightly, and I mean lightly, hitting the inner fender area. Not the lip, but up inside the fender as it is rounded and not squared off and the tires, being 4" wider than factory, get a little close in there.

I just keep the bags at 7-8 lbs. and it seems to have solved the problem. But you may not be able to completely and safely run this big a tire without air bags.

At least it's a good excuse for the wife to get them. "I'm sorry honey, but it's either ruin a $350 set of tires, or get a $65 air bag setup and have no problems." Worked like a charm. And now I can work on my launches at the track. Good luck.

Phil

budnate

05-12-2003, 01:38 PM

Phil,
I missed the part on cost?,
how much was it per rim before shipping?, and are you happy with the chrome on the rims?

Thnx Bud.

70 gsconvt

05-12-2003, 02:20 PM

Hi, I think total cost was around $420, with shipping for the rims. I do live in Ohio and they came from Specialty Wheel in Oregon.

Quality is first rate. No complaints there. Centers are painted a pretty much flat black. Not sure if it is 100% correct, but they sure look good.

DMoore

05-12-2003, 03:07 PM

I can agree with Phil on the looks. I seen them on his car at Norwalk and they look great, chrome looks great and they really give the car a mean looking stance. Definatly top quality.
Just my opinion

skyphix

05-12-2003, 03:11 PM

And I thought the 275/50/17 and 17x9.5 wheel/tire package I was looking at for the back was big :puzzled:

That looks mean, talk about steamrollers :cool:

70 gsconvt

05-12-2003, 04:29 PM

Like the old saying goes.........

Go Big or Go Home!!!!!!:Brow: :Brow:

tdacton

10-06-2003, 11:09 AM

I'm ordering these wheels and tires myself. But wanted to ask one more time. Has anyone else confirmed all of the measurements for a HT car? Or a 72. I'm only assuming that all frames would be the same location? Has anyone else put these monsters on a HT? Basically with same clearance measurements as Phil? Any one with info? Thanks!
Troy

70 gsconvt

10-06-2003, 11:45 AM

Boy, haven't seen this thread in a while.

If anyone wants to, they can bring their hardtop car over to my house and we could swap them on, just to make absolutely sure. Just pm me and we can set something up.

Phil

tdacton

10-06-2003, 01:35 PM

WOW!!!!!!!!! Can someone in Phil's neck of the woods do this?
If I lived about 2 hours closer I would do it! That is a great offer!
PLLEEEEEAAAASE! Can someone do this for me?????
Troy

Lon Bauer

10-06-2003, 02:44 PM

Phil,
We can try them on my blue 70 hardtop but you have to come to my house since I don't have any brakes. My car does have some bondo around the rear quartes and the molding have been modified a little so that should make things more interesting. I'd say lets do it on Wed because I'll have the digital camera but we might not have time. I could see if I can get the camera over the weekend and we can do it then. Or we can try them on a certain 70 GSX?????????????? not!

Let me know,
Lon

70 gsconvt

10-06-2003, 03:08 PM

Anybody except Lon that is................

Just kidding. I'll see if I can take the tires off and take one over to Lon's house. We're going to look at that 15,000 mile car on Wednesday anyway. Or if Glen's willing, his car might be a better choice. I'd love to see a 1970 GSX, Stage 1, 4-speed car with those wheels on it:Brow:

Phil

70 gsconvt

10-07-2003, 06:22 PM

OK, I talked to my friend Glen Stringfield (he's the guy in the pics above). Anyway, he's got a '70 GSX and we'll be putting one of my back tires on his car and checking the fit. We're going to look at that 15,000 original mile 1970 GS tomorrow. We'll try and do it after that.

Phil

tdacton

10-09-2003, 01:04 PM

Phil,
Just hoping that I'm not pushing you. Just following up to see if the GSX looked good with your wheel and tire combo? I wonder if the 15k car would've filled the wheel wells with your combo?
Keep me posted!
Thanks!
Troy

70 gsconvt

10-09-2003, 03:10 PM

Didn't get to do it last night because we spent too much time with yoyo looking over and convincing him his engine was a 350, not a 455.

We'll try and do it this weekend. Someone is always still welcome to come over. It would sure make things quicker.

Phil

71OLDS

10-21-2003, 09:55 AM

Phil,

I don't have a Buick but I have trying to get bigger rims and tires on my 442. I thought you guys my like to see my 18x10 rims w/305/45/18 Nitto Drag radials.

Our wheel wells must be similar because I had very similar spacing issues from side to side.

A buddy of mine let me put some pics on his site. Since I don't know how to post pics here's the link:

http://geocities.com/rcktpwrd/Joe442.html

70 gsconvt

10-21-2003, 12:05 PM

Sorry I haven't had time to do the fitting yet. Kids have been sick, I'm getting over a cold, blah blah blah.

I'll try and get it done this weekend.

Phil

67Riv

10-21-2003, 09:29 PM

Hey Joe,

That wheel/tire setup is kickass sweet!

In my opinion it gives it the look it should/would have had if wheels and tires that size had been available back in 71. Really fits the car nicely.

Serge.

68 LeSabre 4dr

10-21-2003, 09:34 PM

Sweeet Olds !!:Brow: Had a 68 and a 69 ! Man I loved 'em :Smarty:

:laugh: :TU: :TU:

71OLDS

10-21-2003, 09:54 PM

Thanks guys! I appreciate it. As I told Phil earlier - I've been following his progress with the 325/50/15s while I was trying to fit these babies on my car. It turns out we have similar motors as well. Unfortunately my car is getting a bunch of new projects done (motor, big brakes, interior etc) and won't be back until Spring '04.

68 LeSabre 4dr

10-21-2003, 10:16 PM

Phil ya got me all excited !!!!!!!! :Brow: Hope they work . Looks like ya saved all of us some real guess work !!:TU:

Thanx Phil ! :beer

70 gsconvt

10-27-2003, 04:50 AM

OK everyone, I finally got over to Glen's house with my tires.

Now remember my wheels have a 5-5/8" backspacing. Wheels/tires do fit. There was @3/8" to 1/2" clearance from the frame all around. Tires did not touch exhaust as I was able to stick my entire hand between the exhaust and tires. Bottom shock mount is close, but still had about 1/4" clearance.

The other thing you could do is specify a 5-3/4" backspacing and then you would have a 1/4" to play with and use spacers as needed. You can get a set of them from Summit/Jegs for about $12 a set. They go from 7/32" to almost 1/2". I personally wouldn't go over 1/4" unless you get longer wheel studs.

The only "problem" is still the wheel well lip. You would have to trim it back about 1/4" to 3/8" to ensure that the wheel would not hit at all. This trimming does not go past the chrome trim's mounting screws or get into the welds. A RotoZip makes a very nice, clean cut. Or you can cut just the fender, reinstall the chrome and roll it up for a smoother lip. Either way it'll work with a minimum "hacking" of the car's sheetmetal.

My tires are BFGoodrich DragRadials, 325/50R15's. Tires have a 10.4" tread width and a 12.9" section width. Tires have a 28" diameter. They do make a 295/65 that has a 10" tread, 12.6" section width, but they are 29.9" tall. So they are .3" narrower and that may be enough to solve that problem. But I'm not going to go and buy a pair to try.

M&H Tires make a tire called a Muscle Car Drag DOT tire. It is there N50/15. It has a 11" tread, but only a 12" section width and is 28.2" in diameter. It's similar to an ET Street, but with a bit more tread. I think I will be trying out a pair of these when my DragRadials "wear out".

All tires can be checked out at http://www.jegs.com/. Their tire section has all the dimensions on all the tires they sell. I love it. Summit does, but there website is a bit of a pain to navigate.

Good luck.

Phil

NOTNSS

10-31-2003, 10:12 AM

70 gsconvt said:OK everyone, I finally got over to Glen's house with my tires.

Now remember my wheels have a 5-5/8" backspacing. Wheels/tires do fit. There was @3/8" to 1/2" clearance from the frame all around. Tires did not touch exhaust as I was able to stick my entire hand between the exhaust and tires. Bottom shock mount is close, but still had about 1/4" clearance.

The other thing you could do is specify a 5-3/4" backspacing and then you would have a 1/4" to play with and use spacers as needed. You can get a set of them from Summit/Jegs for about $12 a set. They go from 7/32" to almost 1/2". I personally wouldn't go over 1/4" unless you get longer wheel studs.

The only "problem" is still the wheel well lip. You would have to trim it back about 1/4" to 3/8" to ensure that the wheel would not hit at all. This trimming does not go past the chrome trim's mounting screws or get into the welds. A RotoZip makes a very nice, clean cut. Or you can cut just the fender, reinstall the chrome and roll it up for a smoother lip. Either way it'll work with a minimum "hacking" of the car's sheetmetal.

My tires are BFGoodrich DragRadials, 325/50R15's. Tires have a 10.4" tread width and a 12.9" section width. Tires have a 28" diameter. They do make a 295/65 that has a 10" tread, 12.6" section width, but they are 29.9" tall. So they are .3" narrower and that may be enough to solve that problem. But I'm not going to go and buy a pair to try.

M&H Tires make a tire called a Muscle Car Drag DOT tire. It is there N50/15. It has a 11" tread, but only a 12" section width and is 28.2" in diameter. It's similar to an ET Street, but with a bit more tread. I think I will be trying out a pair of these when my DragRadials "wear out".

All tires can be checked out at http://www.jegs.com/. Their tire section has all the dimensions on all the tires they sell. I love it. Summit does, but there website is a bit of a pain to navigate.

Good luck.

Phil

Phil/gang,

What do you suppose 1/2" narrowed rear end would do for this?
I'm having a 12-bolt built with good bearing ends (no c-clip eliminators) and the procedure is the same as narrowing - I could have it cut back a little to help facilitate bigger wheels. Sound like a plan?

I'll have to do the math from your post Phil.

Thanks.

lcac_man

10-31-2003, 11:49 AM

I don't think rearend width is going to make any difference, I think we're just hitting the wall on how much tire will fit in the wheel well. I think Phil has maxed it out(70-72) with the 325's. I can tell you that they won't work on a 68/69 regardless of backspacing/rearend width, a 305 could possibly be stuffed in there if someone makes one.
It's all in properly measuring for backspacing.

70 gsconvt

10-31-2003, 11:57 AM

You can make the rear shorter, but then you have to adjust the backspacing on the wheels to keep them in position.

A shorter rearend will require less backspacing to keep the tire centered in the wheel well and off of the frame and fender well.

Nothingface5384

11-04-2007, 08:45 PM

hey would the n50s work without no trimming on a 15x8 and 4.5 bs?

my buddies dad has an old pair, they lookedabout the same height as my 275/60s and maybe an inch wider then 295-50s..

70 gsconvt

11-04-2007, 08:47 PM

I think they would look VERY bulgy on a 15x8 rim. And I'd bet money that they'd rub big time on the wheel well if you went over a bump. Since the tires are used, ask him if you can have them mounted and try them out to see what happens. I'd sure be interested to see them on a car.

Nothingface5384

12-16-2007, 09:08 PM

hey 70gs conv, could the fender lip trimming be done well enough to be unnoticable to a car that doesnt have the chrome fender trim?

and do you think a 3inch diameter exhaust and ta perf no hop bars would clear? this will be on my 72 lark.

and should i go with the 5-5/8'or 5-3/4'
thanks a bunch, asthese nice meats should hold up to a tt350 with 3.42 gears... i hope!

Nothingface5384

07-21-2008, 09:13 PM

hey phil. just to doubple check before i venture in to this combo..
they'll fit on a 72 ht lark with a 8.5 rear correct?
just making sure as i'm pretty sure this thread was just about fitting it on a 70 with an 8.2.

70 gsconvt

07-22-2008, 05:20 AM

Hi, yes they should fit on a 72 also. You just have to make sure you get the backspacing right because it is tight. Most wheel manufacturer's have/make a 15x10 with 5.5" backspacing. I got a little extra just in case. One thing I've found letting others try these on their cars is that they are not all the same and vary as much as 1/4" from car to car.

You can always shim the tire out with a spacer, but you can't shove it back in. And to run this tire, you will need air bags in the rear springs to control bounce and I had to trim the top of the wheel well back to the pinch welds to avoid any potential problem of rubbing if the tire did get up in there.

Good luck.