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I'm attempting everything within reason to get better traction and all I care about is straight line traction.

That said, I dont drag race and my only claim to fame is rolling starts in first or second gear etc.
First upgrade was the BMR LCA and the FRPP suspension package which is lowered springs and new race struts.

My second upgrade was to wider rims and tires so I went with a 20x11 rim using a Nitto G2 tire. No real help.

Than went to a different rear tire, the Nitto NTO5 305x30x20. A little bit of an improvement. I am limited in tire size because of the 20" profile of the rims. If I had to do it over again I would have ordered 19" rims to give me a larger tire selection.

Today I ordered J&M adj UCA brace and strut and their LCA relocating brackets.
I asked the guy what hole should I put the LCA's in and he said what did I want out of the car.

I told him and he advised me to put it in the lowest hole.

He told me the FRPP springs aren't ideal for straight line acceleration but they are on and dont plan to change.

The car currently is at rwhp and by mid Dec will have the L&M NSR cams putting me a little lower take off speed but much higher mid and upper range HP

Any suggestions or input.

My gears are OEM, 331's. Haven't found someone who can install gears without the gear whine.


I
 

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Moderator/Admin Dude!
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Toyo R888 or drag radials. If you go with drag radials, watch out for rain in FL!
 

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#1 Mike!
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Don, I'd check with Catmonkey (John) who has a world of experience with wheel and tire sizes as well as rear suspension modifications to improve your adhesion. If you'd stop increasing the horsepower, you wouldn't have these issues plaguing you! ?
 

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A 1” thick block of wood under the accelerator.
 

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Discussion Starter #6
Don, I'd check with Catmonkey (John) who has a world of experience with wheel and tire sizes as well as rear suspension modifications to improve your adhesion. If you'd stop increasing the horsepower, you wouldn't have these issues plaguing you! ?


Ya I hear u Mike .... I made a error when I got the CS 14 rims in a 20 .....should have gotten a 19 inch instead
 

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Suspension mods are not likely to help until you have some semblance of traction. Suspension mods are more to tweak the characteristics of the launch to improve weight transfer, but control arms and springs aren't going to change anything when you stab the gas and overpower the tires. Not many DOT approved tires are going to do the job north of 700 rwhp. When the alternative is driving around with drag slicks, it might be time to considered lowering boost. My combination is no better and I've decided I'm going to swap to a bigger upper and see what that does for me.
 

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Don,
I wasn't trying to be a dick when I said about stomping on the fun pedal, when you have a 700 HP car and stomp on the gas one thing is for sure, the back tires are going to break loose.

As John mentioned and a a VERY good idea, is to go with a bigger blower pulley to lower the boost, that will solve a big part of the issue, or maybe look at your rear gear ratio.

My 11 (Ported Eaton)W/ 3.73 I had a hard time getting traction but 09 (Trinity) W/ 3.31 was way better.

Colin
 

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Suspension mods are not likely to help until you have some semblance of traction. Suspension mods are more to tweak the characteristics of the launch to improve weight transfer, but control arms and springs aren't going to change anything when you stab the gas and overpower the tires. Not many DOT approved tires are going to do the job north of 700 rwhp. When the alternative is driving around with drag slicks, it might be time to considered lowering boost. My combination is no better and I've decided I'm going to swap to a bigger upper and see what that does for me.
John, this really sounds like the voice of reality. I've rarely been one to stab the throttle from a dead stop because it'll just break the tires loose and potentially break parts over time. As you know, that's also why I stayed with the 2.6" pulley when I bought your ported Gen 2. Some day it's possible I may bump up to a 2.5 or 2.4 while staying with the locally available 91 octane gas, and I suspect a 2.4 bumping me up another 2lbs of boost would put me over 650rwhp but still below your 700rwhp number.
 

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The cams may tone down the torque band enough to where breaking the tires loose is not as big a problem, so I'd wait and see. I just wanted to chime in that suspension bits are not likely to improve his situation. Sure they make the car more controlled, but the traction issue will remain. Don already has 3.31s and I really think he's going to need lower gears to be happy with the cam.

I'm already running the largest tire I can stuff back there. Going to an R888 over the Sport Cup 2 might help, but when I'm breaking the tires loose at part throttle, it just occurs to me that the answer lies in dialing this thing back and match the engine to the tire. I've been calculating theoretical CFM based on the blower ratio and engine speed and while I'm probably just at or below 18 psi, I figure I'm pushing more CFM than a 2.3 with stock lower and a 2.4" upper. I'm running 2.65 with a 2.8" upper and a 10% ATI lower. I have a 3", which I plan to install, but I'll probably get a 3.2" to try after that. The 3" will put me on par with a 2.3 and 2.4" pulley with a stock balancer.

The silver lining is a pulley swap can be achieved in under 30 minutes with the VMP hub. The lower boost levels should help with IAT2s.
 

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Discussion Starter #11
Suspension mods are not likely to help until you have some semblance of traction. Suspension mods are more to tweak the characteristics of the launch to improve weight transfer, but control arms and springs aren't going to change anything when you stab the gas and overpower the tires. Not many DOT approved tires are going to do the job north of 700 rwhp. When the alternative is driving around with drag slicks, it might be time to considered lowering boost. My combination is no better and I've decided I'm going to swap to a bigger upper and see what that does for me.

John

Thank you again for a great straight forward answer. At least I am set up with a decent rear rim at 11"

The problem lies in the 20" diameter. Limited selection among high perf tires.
Combine the limited tires available and my current front tires at a 27.1 OD, this REALLY limits my rear tire selection from fitting to meeting abs demands.
However I think I have solved the problem by going to a 245x40x20 front tire (28.68OD) and this allows me a lot more rear tire options which most seem to be at the 28.5+/- OD
As I put more miles on the NTO5's, they are hooking up better

When the cams go in this should help traction since my torque is going to be significantly lower.

Im leaving my OEM 331 gears in for the time being.

John, I can buy through american muscle this kit


IS this over kill or just go with the secondary chains only
 

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John

Thank you again for a great straight forward answer. At least I am set up with a decent rear rim at 11"

The problem lies in the 20" diameter. Limited selection among high perf tires.
Combine the limited tires available and my current front tires at a 27.1 OD, this REALLY limits my rear tire selection from fitting to meeting abs demands.
However I think I have solved the problem by going to a 245x40x20 front tire (28.68OD) and this allows me a lot more rear tire options which most seem to be at the 28.5+/- OD
As I put more miles on the NTO5's, they are hooking up better

When the cams go in this should help traction since my torque is going to be significantly lower.

Im leaving my OEM 331 gears in for the time being.

John, I can buy through american muscle this kit


IS this over kill or just go with the secondary chains only
Don, I have NT05 tires on my 00R. They are fantastic, but I’d consider them more of a road course tire than a straight line grip tire. They do have a tread wear rating of 200, meaning softer compound, but R888s have a 100 rating.

If you plan to stick with 20” wheels, look into the Sport Cup 2 tires that were developed specifically for the 2020 GT500. The rear tires on the new car are 315s. Of course the SC2s are a road course tire too, but they had fantastic traction from what I experienced.
 

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Discussion Starter #13
Don, I have NT05 tires on my 00R. They are fantastic, but I’d consider them more of a road course tire than a straight line grip tire. They do have a tread wear rating of 200, meaning softer compound, but R888s have a 100 rating.

If you plan to stick with 20” wheels, look into the Sport Cup 2 tires that were developed specifically for the 2020 GT500. The rear tires on the new car are 315s. Of course the SC2s are a road course tire too, but they had fantastic traction from what I experienced.

Tim

I looked at a awful lot of tires last night and to get a decent rear tire I have to go with a higher diameter front tire in the range of 28.5.
My current fronts are a 255x35x20 at 27.1OD

don
 

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The problem lies in the 20" diameter. Limited selection among high perf tires.
Combine the limited tires available and my current front tires at a 27.1 OD, this REALLY limits my rear tire selection from fitting to meeting abs demands.
However I think I have solved the problem by going to a 245x40x20 front tire (28.68OD) and this allows me a lot more rear tire options which most seem to be at the 28.5+/- OD
As I put more miles on the NTO5's, they are hooking up better
You don't need to match them that closely. I'd go 285/35-20 if you rim width is wide enough. They are 28" and they will fit. I know, I run them. I had 284/40-19s before that and they are the exact same dimensions. Any taller than that and I think your tire will rub on the spring mount for the strut. The 285s were close, but the way it mounts the clearance stays the same regardless of tire articulation

John, I can buy through american muscle this kit


IS this over kill or just go with the secondary chains only
The timing chain cover will have to come off to install the primary chains, chain guides and primary tensioners, which will increase your cost to install, but check with VMP to see if their quote increases. I have no idea of how they quote their cam install and what work they intend to perform. It's not really overkill with your mileage, but could increase your install budget.
 

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A couple of things, you stated that you wanted straight line acceleration, but don't drag race, so I assume that you are not happy with off corner performance because of power over steer. this spawned the post "suspensions in general"
You have to realize that these cars are putting out as much horsepower as early top fuel dragsters, the Cobra Jets are running in the 8s. Someplace, on YouTube is a video for a modded mustang accelerating on the highway, the tire marks never quit except during gear changes, they literally go for over a mile.
Also with regards to gear whine, the 8.8 is really prone to gear whine, I don't know if it's the harmonics or the design, but they are inherently noisy, when you are spinning the ring and pinion even faster, it just exacerbates the problem, this has been on going since the 8.8 first came out. I would recommend you stick with Ford gears, not aftermarket.
 
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