I finally have a set of 18s inbound that will be sent out for widening in the spirit of the SpinMonster/TractionMonster modification.

My questions/concerns:

1. How wide can I make the rim without having to use spacers and/or file/grind off metal like Powerlabs had to in his thread regarding his experience with this modification?

2. Based on the width I can make the rim in response to the question above, how wide of a tire can I install on the rear without it sticking out of the fender and/or having a threat of rubbing something?

3. Once I do the mod, should I lower the car and, if so, should I do it on the stock bolts or should I get aftermarket lowering bolts?

4. Which R compound rubber should I run? A good friend of mine with three very successful and heavily modified time attack cars (that he still drives on the street, two of the daily) has made one suggestion, I see others made on the forum. I will be attacking the corners with some vigor more regularly than I test my straight line acceleration but I also want traction in a straight line so that I can improve my 60' time. The best 60' time I can achieve on the stock SuperCar RFs is 2.0 and I am looking to improve upon the same.

Thanks in advance for your responses.

 

1. 11" is as wide as I would suggest you go

2. 305 is as wide as I would suggest you go

3. That's up to you. The stock lowering bolts are fine up to about 1/2" in the rear and a bit more in the front. Any more than that and you may compromise the suspension characteristics

4. Opinions vary on which R-compound, but a good road-racing tire is not a good drag tire and vice-versa.

San

 

I just got all the details on my setup ironed out today and my fronts are being sent out tomorrow to be widened to 10.5". I also bought 305/35/18 M/T ET Street Radials. My car is lowered all the way on the stock bolts but I shouldn't have any rubbing problems. According to Spin and Powerlabs the wheel will stick out 4mm further than the stock rear wheel which isn't enough to cause rubbing, even with a 305 tire. Powerlabs even went with a 1/4" spacer to push the wheel/tire out even more but I don't think he is lowered if I recall correctly. I'm going to see what mine looks like without a spacer but I'm guessing I'll end up going with a 1/4" as well because I want the tire to be nice and flush.

 

The control arms do not have to be ground down with an 11" wide wheel. Mine never touched in 2 years.

Use a 305 tire like a Nitto 555r2 or the R888 of the same size. Handling wont be better.

 

I think the entire spacer topic is really causing issues that shouldnt be.

The tire isnt completely under the fender as it sits stock and rock chips will be an issue with a spacer in the 3/9 oclock position on the rear fenders.

This is how it looks with the 305/35/18 Nitto 555r2:

The next is with the MT 305/35/18 ET street on an 11" wide with no spacer:


I dont see why you would want the wheel to ride outside the fender in some places like that with no benefit. It already is out 1/4" from where the 19" stock rim sits.

In this picture you see where the wheel is already riding the line where rock chips will be an issue and there is no spacer:


In my opinion people are placing way too much emphasis on the spacer idea which is complicating a very simple mod that works without issue as it is. I agree the front wheel sits in a bit far but thats the way it came from the factory so why does it become an issue when the rears are widened? Do the mod and live with it. I have no rock chips or other issues with this 11" wide wheel and the stickiest tire available.

Please understand the inner fender liner is not flush with the outside visible fender. Stop looking at the outside of the fender only, and bend down to see where the liner is before you move the wheel out any more.

The only time you will ever have control arm contact is jacking up the car and thats as simple as jacking from the control arm. I ran this for 2 years and didnt have any contact and belive me, I tried to make it touch. I DIDNT REMOVE ANYTHING FROM THE CONTROL ARM AND I DONT CARE THAT I HAVE TO JACK UP EACH SIDE OF THE CAR ONE AT A TIME TO CHANGE THE WHEELS IF AND WHEN THAT MAY HAPPEN.

Its my sincere wish that many, many people do this mod and enjoy the benefits of traction. I didnt do it and keep the best way of going fast in a vette to myself because I wanted it copied. I get upset when a great mod is ruined when people think there si something wrong or needing a band-aid fix when its awesome on its own standing. The wheels do not need a spacer to look good. They already are 1/4" out from the 19" rim's position and looks great jujst like that. Dont let the spacer stall you on the single best thing you can do to make your car the fastest it can be. Use it, say thanks if you like and make a donation to St Judes

 

I am using a 11" wide wheel with a 305/35/18 for two years and nothing ever touched in actual use....fenders, liners, or control arms.

 

If you insist on running a spacer (which isn't necessary or prudent), you should invest in some splash guards to try to minimize the damage to your fenders. I would heed SpinMonster's advice and forget about running a spacer. I can only think of cons and no pros.

San

 

Thanks.

I will go with your advice and go 11" wide with some 305s. I am looking forward to the extra stick as I am sick of my buddy having a .5 advantage in the first 60' and I am looking forward to having the ability to stick it in the corners. Him and his damn awd ricer cars (STI and EVO)

Hey, if you know the address to St. Judes for mailing in donations, please advise as I will, once again, take your advice and send in a check from the office account.

I will advise as to the results upon completion.........

 

I've already ordered splash guards. The only reason I would consider running a spacer is IF I feel that the wheel/tire should be pushed out a little more SIMPLY FOR LOOKS. What I said above is that I would see what it looks like without a spacer and if I think it needs to come out some more to look right I will add a 1/4" spacer. IMO the stock wheels and tires need to stick out about a 1/2" more than what they do. Not completely outside the fender mind you, but just enough to where the top of the tire is almost flush with the top of the fender. This is only my personal opinion and not intended to mess up anyones idea of a good mod. I may love the way it looks with no spacer.....I'll know in a couple weeks.

I much appreciate the R&D you put into this Spin and I will be making a donation to St. Judes as well.

 

Yeah, I saw your purchase yesterday. Just make sure your tires will clear your fender or under heavy compression, you'll need new fenders. It will definately affect your LOOKS.

San

 

Exactly, it is all about choices and what YOU like best...

 

Copy that! I'm not looking for a body shop bill right now. However, it would be a good excuse to give the wife as to why I had to get a widebody kit....

 

I evenually will be using a widened 19 and am thinking of a 1/4" spacer so I dont have to cut the fender liner to clear the 325 tire. I know this is not an issue for guys using 18's with 305.