Mr. IROC-Z

iTrader: (1)

I am not too familiar on how Niel did his. I think he just widened the out side fender lips, but I am sure he also had to do some internal fender mods as well to fit those massive 335's!
If all goes well, I hope not to use any spacers. I don't like the look of the wheels being spaced out. I want the wheels to remain inside as much as possible.
Thanks,
Tommy

Mr. IROC-Z

iTrader: (1)

Well...just got some bad news from the shop....they said they won't be able to do the work on the car because of 'liability' issues!
Lol, they said that they were not sure if they could put the car back together to make it stiff again once they started cutting away at all that sheet metal.
Thus, once again, true to the title of this post, "The fuking saga continues'.
To tell you guys the truth, I have had it with this fuking project. It's been two long years and everything on this damn car has not come easy. For the money I have spent on this project, I could have gotten myself a nice Z06 or a CTS-V. ***..I should have just left the car alone..a stock 305/speed with 18's.
Ah crap...ok guys sorry...just had to vent my frustrations!
Time to look for a new shop to do the work ....saga continues.....

matt_p

I'm telling you, get the proper height tires. 35 series instead of 40. They'll fit. Probably need 2.25" billet spacers and should be able to bolt them on. You are doing it the hard way. 295/40 is just too tall.

camarojustin

I hear you on that.
My car has been nothing but headaches too.
Spent $20000 in the last year and still not on the road yet LOL
You need to completely remove the side of the spring pocket which is part of the unibody frame to get those to fit. you can see in my pics that I have maybe a 1/4" between the tire and the spring pocket. with a 6" of bs.

New thought... Why not get a fourth gen rear?
They'd fit perfectly!
2" wider will make your tire sit exactly where mine does and would cost way less than the body work.

Mr. IROC-Z

iTrader: (1)

It's not the height of the tire..the tires will fit height wise...it's the width.
I have a 18x11 rim with 8' of backspace. I may have to try the spacers but I really hate the look of the wheels being moved out towards the fender. All is not lost yet. I have several other shops I need to talk to.
I am going to do this the right way..or not at all.

matt_p

With an 11" wide wheel, I don't think you have much choice. With 8 inch's of backspace you'll need spacers or a 4th gen rear end. My 18x9.5's have 7.6 inch's of backspace. 5.5" of backspace is about the max one can have with a wheel mounted directly on the axle. Hence my 2 inch spacer.

Putting them on without the billet spacers would be impossible, unless you have a 4thgen rear end. Do you?

You may need spacers to assist in making room. You may need 2.5" to fit but the the wheel would probably be at the fender lip. So maybe consider using a 1.75" spacer and leaving only a small amount of clearancing.

edit:
I just got back from my gf's where a started this post and took a few measurements. The lower control arm is ~7.25 inch's from the mounting surface of my drum brakes. Panhard bar brackets is ~8 inch's from the mounting surface of the drum. Bump stop is definitely in the way. You have to seriously expose the upper spring to get fitment.

You are making a lot of work for yourself. Moving the wheel towards the fender isn't that bad as long as it doesn't go past the lip.

WillSpeedy

Not to mention that the wheel wells are flat on top because it's a vert. It's a sweet idea but i think you bit off more than you can chew, it's going to cost a fortune just to fit them. Should have gone 10" with 6" BS. Spacers are the only way those are going to fit. Like Matt said.

Orr89RocZ

iTrader: (20)

looks great! i'd just do a 4th gen rear, it should fit well with those wheels. most 4th gen guys run 10 inch wide rims with 7-7.5 inch backspacing, so a 2inch spacer or 4th gen rear will work ok.

superirocz

iTrader: (5)

Why not do what all the ls-1 guys do? Just do a search on ls1tech.com for "mini tub" also checkout wolfecraft.com for there mini tub kit they sell for 4th gens. You run a smaller spring and just weld a plate to box in the frame rail you cut out.

Jeremy Z28

iTrader: (5)

..

Gr89RS

iTrader: (5)

Sure they would fit, but they would stick out 2 inches farther than normal on BOTH sides..

Orr89RocZ

iTrader: (20)

they will stick out some if you get a LS1 car rear end. its actually to about fenderlip, but looks like it sticks out farther just because of the way the fenders are cut. the tops flare out alot while the body sides dont so they look like they stick out alot. Looks like your sporting some very wide rims/tires but i'm not. In his case tho, with 11 inch wide rims, its gonna fill up the inside of the well so its gonna look really good. Big wide tires look great on these cars

1 DwnCam

Chalk up another Amen! on the wolf race craft "minitub" kit for 4th gens. I think this is totally do able. You have come this far, might as well bust out the plasma cutter and go to town.

LilJayV10

iTrader: (5)

Use some spacers.

dennisbernal91z

iTrader: (2)

I run 335s on 11" rims. I have a 3rd gen moser 12 bolt and they stick out an inch I would say. I run 2" spacers. I am going to go down to 315s in a month and machin down my spacers. They will more than tuck after I do that. Cut all the inner spring pocket off. i did, and have 1400 miles on the car now, with no issues at all. Hell my ties stick out now, and wherever I go all people say is how great it looks, and I don't even like it, haha. I will post some pics of what I did.

cut this out


In this shot you can see how much room there is down there. Try and imagine a Nitto 555R (315) instead of these used Viper 335s. (more room, less bulge)


Here you can see how much they bulge out, not acceptable to me, but people at shows just can't get enough of it.


Finally, a pic of the car as it is now, drivable. In the next few weeks, I will get the 315s and machine the spacers. I have no idea how much I am going to shave off of them, but I assume it will be around .25-.5 of an inch.

I will post pics of the entire ordeal. If you guys wanna see almost 400 pics of my being built by me, go to my CD site, and feel free to ask questions.

Later.

-Dennis

1 DwnCam

If it was possible to stuff that 335 mm tire completely in the wheel well with out hanging past the fenders. That would be tighter than a virgin on prom night.

dennisbernal91z

iTrader: (2)

Interesting analogy. it IS in fact possible to tuck 315s though. Thats like a virgin on any other night.... I guess. haha.

I will be picking up tires and brakes in the next few weeks. i am going Nitto all around, C5 front and LS1 rear.

Mr. IROC-Z

iTrader: (1)

Dennis,
Love your site...and the car!
That piece that you cut out is what I need to cut out also, in addition to alot of other shitt!
Right now, the project is on hold until I can additional resources to complete the rear end.
Definitely keep us updated on your ride. I want to see how you can stuff those 315's! I will not do this project unless I can completely tuck the rear tires. If I can't do that, then I will throw in the towel and just go back to 18x9's in the rear.
Thanks,
Tommy

xpndbl3

iTrader: (5)

i'm going to put 325s under my camaro 13.5" section width mounted on 15x10s, we'll see how that goes this winter, totally doable since others have done it that I know. 325/50R15 so 28" tall, same size as a 28x10.50W slick.

dennisbernal91z

iTrader: (2)

That will be interesting to say the least. Can't wait to see it xpndbl3.

Mr. IROC-Z

iTrader: (1)

Hi Guys,
After some work to the inner fenders, my buddy was able to mount one of the tires. As you can see, it fits perfectly in there. We still need to do some more work, and get some longer wheel studs (we are using some shims to move the wheel out a bit).

82 Indy Z

Hey IROC,

That looks verrry nice. Looks like you did not have to perform surgery after all. How much room do you have on the inside fender? The tire width looks a tad bit narrower than the wheel. Is it, or just an optical illusion? I plan on doing something like this for my 82 camaro, but I don't have as much of a problem since I plan to keep my car a the stock height. I am looking to try an 18x10 IROC wheel with a Mickey Thompson S/R Radial 28x12-18.

Great job, glad no surgery was needed. Keep the pics comming

matt_p

Man thats a tight fit. Hope you got stiff rear springs. From the looks of it, you probably didn't need to widen the wheel to 11", 10 or 10.5 would've been enough but ohwell.

Any pic of the inner well mods?

Mr. IROC-Z

iTrader: (1)

Ya..you guys are right. I should have gone 18x10's. The 295's on the 18x11 are stretched to the limit!
From the look of things though, I believe I can go 315/30's for the next round.

Tommy

1 DwnCam

Can we see some wheel well pictures?

dennisbernal91z

iTrader: (2)

nice job. Comin' along I see. I see you are running Falken tires. (right?) They look like a nice tread pattern. What made you go with those. I am trying to get my head straight finding the best 315 tire for the $. I am pretty sure I am going to go with Nitto 555Rs. I will do a google about those Falkens, but if you know anything let me know. Thanks.

-Dennis

Mr. IROC-Z

iTrader: (1)

Dennis, I wanted a nice beefy tire with some good side wall. Falken is the only tire company that makes this size tire...295/40/18. Although if I had to redo it again, I would probably go with a 35 series tire. I will be going to 315's for the next set of tires. I will probably go with the Michellin Potenzas S03.

BMmonteSS

Those tires are basically a slightly more streetable R-compound race tire. They have a 200 treadwear, and mostly because that is required to run in the STS and STX classes. I've heard of guys getting 10 to 15K out of them depending on how often you auto-x them. Be warned these tires are designed for auto-x, any open tracking will quickly overheat these tires. Best times on an auto-x course are had when water is used to cool the tire between rounds.

If you are just looking for a street tire this is probably not the tire for you. It's aimed more for the auto-xer who wants to drive on his tires to the track.

dennisbernal91z

iTrader: (2)

Right on. thanks for the heads up. Looks like I will stick with the Nitto 555Rs then.

//<86TA>\\

iTrader: (14)

any progress? any pics of what you did in the fenderwells? Im going to try to stuff some big rubber in my wheelwell too this winter, i was thinking about 315's as well. I wanted 335 just for the WOW factor, but without major surgery its not going to happen, and i like the way your wheels tuck under the car.

You do nice work

Stephen

iTrader: (12)

Now if some company would step up, and buld 17" &18" GTA crosslace wheels! The make the 2nd gen snowflakes, but they aren't cheap, or else I'd get a set of those.

Beast407

I am the Manufacturing Engineer for the local division of an OEM wheel supplier. While it may look simple, the development and manufacture of an OEM-spec cast aluminum wheel is an extremely detailed and controlled science.

I can tell you that welding is forbidden in the manufacturing of any OEM cast aluminum wheel, for good reason, regardless of manufacturer.

I would strongly recommend against having any cast aluminum wheel repaired or modified in any way.

Mr. IROC-Z

iTrader: (1)

What is wrong with widening the wheels? Countless numbers of wheels have been modified with no issues. While I am sure there could be some issues with modifying anything, I have not heard of any catastrophic wheel failures.

As well, I have sent emails, letters, and even spoken to various company officials to manufacturer larger size OEM style wheels. At this time, all that is available in the IROC style wheel is a 18x8. A 8' wheel is just not wide enough. I think these guys are missing out on big potentials profits to sell more wheels if only they can make them in various sizes.

Tommy

Orr89RocZ

iTrader: (20)

i wish ppl would make larger crosslace wheels and the 88-90 double line irocz wheels. they are nice factory wheels

82 Indy Z

I would agree with Mr. IROC and his statement that there is a void to be filled for people that want a factory wheel look with the added width and size. I personally want a wheel that is wider than the stock wheel but retains the stock look on the car. I would like to purchase two 18X10 IROC wheels for the rear and two 18X8 for the front without sending them off to be modified. Hell, I would even go for 16X10's if they were available. The correct offset to fit would be great, eliminating the need for spacers, would be cool too. I love the look my car has with the factory wheels and people are always asking what year my car is. When I tell them it is an 82 they don't believe it because the factory wheels look sharp even though they are 15+ years old.

Orr89RocZ

iTrader: (20)

yep that is a big problem. you can widen them but you screw up the offsets and need spacers.

Tobias05

makes me want to add two inches width to my slp zr1s...

Beast407

As I mentioned above, I am limiting my comments to cast aluminum wheels.

In welding, you have the base metal and the filler metal, which usually possesses superior mechanical properties (ultimate tensile strength, yield strength) than the base metal. This is good. Unfortunately, adjacent to either side of the weld you wind up with what is known as the heat affected zone. The properties of the heat affected zone are not on par with either the base or filler metal. The width of the heat affected zone is primarily determined by the welding process used and the heat input.

All castings have some level of porosity. You might have to look extremely hard, but it's there. This is one of the reasons why cast aluminum is more challenging to weld than wrought aluminum. Combined this inherent porosity, which acts as a stress riser, the heat affected zone mentioned above, and the cyclic loading nature of a rotating wheel and the possibility exists for crack growth.

If you wish to reduce the effect of the heat affected zone mentioned above you will need to re-heat treat the wheel. This entails heating to around 1000 deg. F for a prescribed period followed by water quench. Now your heat affected zone is removed, but your wheel has distorted and requires almost complete remachining which reduces the section modulus's available. In the repair of OEM wheels this usually puts you below Minimum Material Condition.

OEM wheels are 100% fluoroscopic (real-time X-ray) inspected along with testing to destruction of samples for fatigue, impact, torque retention, and mechanical properties. Fatigue and impact involve testing at both Maximum and Minimum Material Conditions, with fatigue requirements of several million cycles (rotations) at load. The test results of a wheel machined under Minimum Material Condition are not promising but nevertheless unknown. Yes, the fatigue testing cell is caged off and, yes, we have been witness to some pretty substantial catastrophic wheel failures.

Now, I'm not saying your wheels will necessarily explode on the freeway and I certainly do not wish ill will. I'm sure the company that widened them feels they did a quality job. I don't know their exact process for widening, but I'd venture to guess it did not involve any fatigue testing. Most likely a crack would manifest itself as a slow air leak that increases with mileage.

All I'm offering is a professional opinion that is shared by my employer and the OEM wheel industry. On that note, we hear many requests for aftermarket wheels. The issue with aftermarket wheels is volume.

While you can charge more for an aftermarket wheel the volume just isn't there and you are taking away OEM capacity for wheels that are not ordered and may not be sold and you don't want to risk missing an OEM wheel shipment and shutting down an assembly line.

Apologies for the long dissertation. There was a very good article on wheel repair industry some time ago that I will post or link if I can find it.

Thank you for your time.

Mr. IROC-Z

iTrader: (1)

Beast,
Thank you for filling us all in on this issue. I was really unaware of the down sides of widening the wheels. You definitely seem like you know your subject matter! The good news is that the car is only a weekend warrior so it shouldn't see much action.
Although blowing a wheel while doing 80+mph on the highway does seem scary! Now I will have that in the back of mind! Oh well..even more sense not to speed!
Best regards,
Tommy

dennisbernal91z

iTrader: (2)

I am a mech. engineer and I totally see where he is coming from. All I do is deal with things like this when designing automotive switches and actuators. Honeslty though, I feel like you should be OK. The main thing is that they need to be balanced well. With an inbalance, you will introduce a strong repeating force that will eat away at any weak point near the weld. Assuming the company did a good job, they should know all about the porosity of the aluminum and welded the wheel in a way to reduce the heat affected zone as much as possible.

Anyways, good luck, make sure you are balanced and I think you will be just fine.

Should be a blast to drive

85_ZED28

I honestly can't see how any wheel manufacturer could see 17x9 (or 18x 9&10) polished single line IROCs as a risk. They'd sell like freakin' hotcakes IMO.

Also, why the heck doesn't SLP make a 17x9 version of their zr1 style thirdgen rims? Same deal, they'd sell a whole lot more of them guaranteed.

dennisbernal91z

iTrader: (2)

True. I dunno.

But at the end of the day, in todays world of rims, it is a whole lot easier to just buy spacers and do whatever the hell you want in terms of rims. Get a set off ebay. I did and am pushing 400 Hp through them. They are FINE. People bash them and crap, I havn't had a loose nut or any problems AT ALL. I would do it again. $90 bucks for 2 2" spacers. Get 2 sets and be done with it. Thats how I run my 17x11" and 17x9.5.

If anything they are even better than running real rims, cuz to change your back spaceing all you have to do is machine the spacer down a little at a shop. Maybe 20 bucks. and you can move your rims in if you want. Thats what I am doing. I found that the 2" ones are too big, so all I have to do is figure out how much more room I have back there, and have it machined off. BAM rims are tucked and I have the spacers for the next set of rims, in case I ever wanna change them. You can even polish them if you want.

I am a spacer supporter, haha.

Beast407

Below is the link to an entertaining article that was making the industry rounds some time ago:

http://www.boston.com/cars/news/arti...urn_on_safety/

doc

Your problem is both width AND diameter (but mainly tire diameter). You should have stuck much closer to the factory tire diameter of 25.7"... I am running P295/35R18 BFG Drag Radials on the back of my '87 IROCZ using wheels having 58mm offset and 2.0" billet adapters from Skulte. No fender or suspension mods required. The 295/35R18's are 26.1" in OD. The 295s that you have are about 27.3" in diameter.

Mr. IROC-Z

iTrader: (1)

Hi Doc,
Thanks for that info. The main thing I want to set clear is that I want the car to have an absolutely amazing stance. To me, that means tucking the top of the tire in the front and in the rear. As such, I am not sure how you are running a 2" adapter without your wheel sticking outside the fender.
I guess, I could do the same thing, but it would not achieve the look I am wanting. The images I posted above is how the car will actually sit. I just love the agressiveness of the stance! Being low just looks so awesome to me!
Thanks,
Tommy

Mr. IROC-Z

iTrader: (1)

Hi Folks,
Just want to post some 'teaser' pics of the car finally on the ground, and show you how she looks with the 18x11's. We will be removing the rear end tomorrow to have it rebuilt, so I will take some shots of the inner fender work.

Guest

Not sure about that one. As far as I know, the 87 GTA wheel is a cast center section with hoop of unknown origin (may be cast or machined, no clue) but they are most certainly welded together 2 piece wheels. Later wheels were all cast. I'm sure there are likely other exceptions to the rule.

Thanks for the other insight though.

GuitarJunki17

iTrader: (1)

Wow dude, those look freaking amazing! I would love to do something like that with my wheels. Out of curiosity (and maybe I missed it), what are the sizes of the front wheels?
Enough with the teasers and show us some more!

Mr. IROC-Z

iTrader: (1)

Fronts are 18x8...255/45/18.
They do seem a bit inadequate now when paired with the 18x11's...hehe.

Tommy

dennisbernal91z

iTrader: (2)

nice. I just got my 315 Nittor 555rs that I will be mounting this weekend. And over next week I will be maching my spacers to tuck them further.

Yours look great.