Filled the transmission with royal purple synchromax. The trans and the engine were shipped dry and there was no warning with either. I almost didn't check the trans because it only has a few thousand miles, I thought it would be fine. It was empty to my surprise!

I just ran clear tubing down around the shifter boot and in to transmission, then I cut a hole in the bottom of the bottle and let gravity do the work. I made the hose long enough that I was dealing with the oil outside the car in case of an accident. This oil stinks, like rear diff fluid.

 

Well, how about those AM wheels?

 

I've been thinking about those AM wheels, they have more offset and could be widened 1/2" more than my factory wheels. I could still put on the 325 tire if I went that route. Although they look similar to the wheels I have they aren't the same, I like them but not as much as the factory set.

It looks like I can widen my rear factory rims to 11" and use up to a 12" wide tire, everything should clear. This is still a large rim and a large tire, I'm sure I can be happy with this too.

I'll get the car driving right before I do anything with the wheels, plenty of time to decide.

 

If you're going to run a Toyo R888 or Nitto NT05, it really doesn't matter if you have a 10" or 12" tire...you're going to have traction. At some point it's more for the looks and saying "yeah I'm running 325s) lol

 

Well that's defintely up for discussion. Lexiion came over last night and helped me with the wiring and we talked about it. He told me that when his car had the supercharged 4.6 pushing 550 HP and just under 500 lb of torque that traction was only limited in 1st gear, 2nd gear hooked as long as he was going straight. When he heard people saying online that the 2013/2014 gt500 had terrible traction issues he really didn't believe it. A month ago he dropped in the 5.8 Shelby motor in his mustang and now he believes it. His motor is completely stock and just rolling in to the throttle in 2nd roasts the tires and gets really loose. He's got stock Shelby wheels and I think Michelin tires. Mine isn't stock and I can roll in to 3rd gear at 70 and the car gets loose.

During that discussion we agreed it wasn't HP it was 600lbs+ torque spinning the tires, he said "you should be fine with the ecoboost" I didn't agree. I explained if 600lbs of torque causes huge traction problems I would be there very soon with the ecoboost. The motor before any mods puts out 420lbs, with a canned tune it's plus 100lbs. I'm going far past a canned tune so reaching 600lbs torque should be in my future.

What I don't want to do is spend $3k+ on wheels after modifying them and adding race tires and not have enough traction in the future. If I go with the widest tire possible then I wouldn't have any regrets. It really doesn't cost more at this point to go with a 10" tire or 12" tire. I also don't have any track tires for the Shelby, these could double for that car too. I would like to have enough traction that I can actually go WOT in 1st and 2nd while racing, which I've never come close to doing in the Shelby. I should take a video launching the shelby just for fun, it's quite comical. It spins the tires with 1/2 throttle without dumping the clutch. Every car beats me off the line, then I real them all in at the end of 2nd gear like they are tied to a stump. Can I launch the car without without too much spinning? Sure I do it every time I race, I'm just leaving lots of HP and torque on the table to do it. If I could dump the clutch in first and the car launched instead....that would be awesome. I want that for the ecoboost mustang, I just need more tire!

Of course I realize I could just throw slicks on either car, but I like driving safely on the street. I'll eventually buy a set of slicks for the drag strip but driving around on the street with a set of slicks defeats the purpose of having a "sleeper"

 

Did you ever try to launch your Shelby with LC on? I tested that on Monday and that helps you get off the line pretty quick, without the tires spinning and breaking loose like crazy...
I think Laserred38's advice for R888 or NT05 for traction is pretty good. Maybe go 305 on the rear with a R888 and you should have decent traction.

LEXiiON

 

Once I started to modify the car the LC started to not be as effective. I've tried using LC at the track and I run faster with it off. If I remember right I was .2-.3 seconds faster with traction control turned off.

I need to check out the r888 and see what sizes they offer in 19". I was looking last night at the 305 NT05 which is a 12.3" tire. It would fit modified factory wheels with the spacer, they should give me good traction.

 

Specs for nt05 in 19"

 

If you are going to use the car on a road racing track, the last thing you need is stuffing the largest possible tires in the back. This will put more weight on the nose, which it definitively doesn't need.
Don't build the car to pose... build it for handling & dynamics. Leave room for suspension travel in extreme conditions. And don't forget great brakes, and brake cooling.


Remember, too, that the frame rails in the back are all but identical to the S550... the S550 is just an updated S197 and is not "all new". It's the width of the wheel wells that increased in the S550.
In the S550 prototypes built on the S197 body, Boss302 rear wheels showed the proper clearance.

 

Building it as a sleeper is far from posing. Most of my racing is drag strip, light to light, hill climbs, and on rare occasion I go to a road course. I disagree about putting a wide tire on the rear, have you seen the tires put on the back of the gt350r? 11.5 in wheels in rear and 11" wheel in the front.

 

And the new Viper ACR. 295's on the front and 355's on the rear.

 

Viper has no relationship to a tall coupe like a Mustang.
The GT350R tires are 1 size larger on the rear. Just 1. To deal with the front end weight of the mustang, they went to 295s on the front. That's a doubtful fit for your car... you could go 285s on the front with the right offset, and 295s on the rear - again with the right offset.
Remember, too, that this is all unsprung weight. Unsprung weight hurts handling, and acceleration. There is a point of no benefit.

 

Ditto.

 

Here's how an S550 IRS mounted in an S197 body would look like for wheel offset:


http://image.automobilemag.com/f/575...ear-view-2.jpg

 

Ecostang, I've actually heard from a number of GT500 owners over the years that it's not at all difficult for the rear tires to break loose under acceleration and I'm sure you're well aware given your collection of Mustangs. There's a good reason why the Corvette, for example, is sporting 335 size tires on the back as opposed to the 285s on the GT500. These modern muscle cars are putting down numbers that were unheard of in the muscle car hay day. Heck even my lowly V6 was once the stuff of dreams and puts down better performance than GT's from not that long ago. They are truly amazing. The down side is that we are still using street radials and getting that much torque to hook up on street tires is a delicate balancing act. It will be very easy for your 3.5 motor to exceed the grip capability of many street tires. My advice is to tuck as wide and grippy a tire as you can get up under that monster so she stays put.

 

Ditto

That's the beauty of building your own car, you get to do whatever you want to it....right or wrong lol

I would really like to keep this thread on course and not have it break down in to a debate about which tire width is the best. I want a huge tire on the back, and before I'm done that's what it will have on it. I can always buy another set of rims for the rear when I take it to autocross, it's that simple.

 

I've been cleaning up the trunk wiring and I'm spraying the floor with rubberized undercoating. I'll finish painting tomorrow, the fumes are strong!

A little more wiring, some painting, and I need to mount the pump and res to be finished with the trunk.

 

Do you have anymore info on this car? I didn't know the IRS had been put in a s197, I didn't find anything online when I looked it up. Thanks

 

I don't think you're going to find one lick of information on that car. It looks like a Ford test mule.

 

Correct, it was a Ford test mule.