Pegasus Solid Aluminium Subframe Bushings

[1JEWLDSSRS]

Originally Posted by Chris49066SS

Oh right on. 17" Welds I presume? I still haven't put my 20's back on the rear yet, even though the seasons over. I love the look of the 18's out back. Gives it that look...which would only be better with some 17s, let alone the 15"...the Carlyle kit is calling my name..

Hey there, yea one of my buddies put the 17's on his 5th gen with 325 hoosiers I think, and he gets them to hook up really nice, plus they look great, nice and fat out back !! lol..

[acammer]

Originally Posted by Chris49066SS

What kind of tire/wheel setup are you running? And are you going for more strip/street/track? Have you thought about doing a smaller diameter wheel?

This is a little against the grain, but I think the ticket with an M6 car is to get on a nice light and short 26" tire, either a 315/30/18 or a 275/40/17 with a Hoosier DR2. I know conventional drag race stick car wisdom is to put on a bias ply with a tall sidewall and dump the clutch and let the tire manage the hit. I don't believe we have the drive-line to handle that kind of abuse, you need to upgrade everything behind the trans to even have a chance, and you'll still be breaking parts.

I prefer a drag radial and a LOT of clutch work to bring the car out of the hole with the tire hooked up the whole way. To do that you need all the 1st gear ratio you can get, so a short tire helps out there. And on the big end that extra 500rpm through the traps is definitely worth some MPH.

It looks a little funny - but you'll find that a lot of the fast all motor stick cars use that approach.

[sixty9fordkiller]

Originally Posted by acammer

This is a little against the grain, but I think the ticket with an M6 car is to get on a nice light and short 26" tire, either a 315/30/18 or a 275/40/17 with a Hoosier DR2. I know conventional drag race stick car wisdom is to put on a bias ply with a tall sidewall and dump the clutch and let the tire manage the hit. I don't believe we have the drive-line to handle that kind of abuse, you need to upgrade everything behind the trans to even have a chance, and you'll still be breaking parts.

I prefer a drag radial and a LOT of clutch work to bring the car out of the hole with the tire hooked up the whole way. To do that you need all the 1st gear ratio you can get, so a short tire helps out there. And on the big end that extra 500rpm through the traps is definitely worth some MPH.

It looks a little funny - but you'll find that a lot of the fast all motor stick cars use that approach.

I can completely agree with the 26" tires on these cars. Especially if you're NA. These ladies are pigs but with an engine that loves to spin up fast, its not something a little gearing can't/wont fix.

my personal best ET when i had only minor boltons:
LT headers, catless mid, true full 3" exhaust, CAI and tune was 12.12 on the factory wheels.

With just a change to 26" slicks (same day), i got into the 11's and a final personal best of 11.87. Looked funny as hell like the car skipped leg day at the gym but she fukn mooved!!!!

the real magic wasnt necessarily the stickier tire but more the effective 3.81 final gear ratio that the smaller overall diameter created with the factory 3.45 differential

now with 3.91 gearing the car will feel like it has 4.32 rear gears when i run the 26" tires


if you are NA (FI guys dont have this issue because of the TQ they make) in one of these cars, using a good combination of lower differential gear with smaller diameter tires is the way to go. you get out of the hole QUICK and shes fast at getting the revs back up when upshifting

[sixty9fordkiller]

here's a video of one i found with 26" tires on it. keep in mind the leg day reference i made. lol

[acammer]

Originally Posted by sixty9fordkiller

I can completely agree with the 26" tires on these cars. Especially if you're NA. These ladies are pigs but with an engine that loves to spin up fast, its not something a little gearing can't/wont fix.

my personal best ET when i had only minor boltons:
LT headers, catless mid, true full 3" exhaust, CAI and tune was 12.12 on the factory tires.

With just a change to 26" slicks (same day), i got into the 11's and a final personal best of 11.87. Looked funny as hell like the car skipped leg day at the gym but she fukn mooved!!!!

the real magic wasnt necessarily the stickier tire but more the effective 3.81 final gear ratio that the smaller overall diameter created with the factory 3.45 differential

now with 3.91 gearing the car will feel like it has 4.32 rear gears when i run the 26" tires


if you are NA (FI guys dont have this issue because of the TQ they make) in one of these cars, using a good combination of lower differential gear with smaller diameter tires is the way to go. you get out of the hole QUICK and shes fast at getting the revs back up when upshifting

Sheesh - I went 12.59@113.49 on similar mods to your 12.12 pass - that's total instanity. What was the trap speed for that pass?

11.87@116 is madness with bolt ons. What was the 60' time like? You got some weight out of the car?

That's really impressive work. Most bolt on cars I see are lucky to run mid 12's. I'll be happy if I can run some mid 11's with the cam only set. I'm full weight, and not the lightest jockey in the stable either.

But yea, that final drive ratio is EVERYTHING to a big heavy car like this. Totally under-appreciated thing. I die every time I see somebody talk about adding 3.91's to an M6 car - I'm like JUST GO 4.10 - no downsides and a lot to be gained.

[Chris49066SS]

Originally Posted by acammer

This is a little against the grain, but I think the ticket with an M6 car is to get on a nice light and short 26" tire, either a 315/30/18 or a 275/40/17 with a Hoosier DR2. I know conventional drag race stick car wisdom is to put on a bias ply with a tall sidewall and dump the clutch and let the tire manage the hit. I don't believe we have the drive-line to handle that kind of abuse, you need to upgrade everything behind the trans to even have a chance, and you'll still be breaking parts.

I prefer a drag radial and a LOT of clutch work to bring the car out of the hole with the tire hooked up the whole way. To do that you need all the 1st gear ratio you can get, so a short tire helps out there. And on the big end that extra 500rpm through the traps is definitely worth some MPH.

It looks a little funny - but you'll find that a lot of the fast all motor stick cars use that approach.

I know you're right. I am going to need a bulletproof drivetrain for my end goals though, because I am going the 15" route. The real question is: Whats going to break first? I can very well see swapping for a TH400 when the 6l80 goes. When the rearend goes (shudder), go solid axle. Its only money right? What do you think about this line of thought, acammer? Unfeasible? Impractical? Wrong platform to attempt it on?

[acammer]

Originally Posted by Chris49066SS

I know you're right. I am going to need a bulletproof drivetrain for my end goals though, because I am going the 15" route. The real question is: Whats going to break first? I can very well see swapping for a TH400 when the 6l80 goes. When the rearend goes (shudder), go solid axle. Its only money right? What do you think about this line of thought, acammer? Unfeasible? Impractical? Wrong platform to attempt it on?

For your goals a TH400 or 4L80 swap probably makes a lot of sense. 6L80s can be made to survive big power, but it's expensive and still seems to be a bit of a lottery. Solid axle conversions aren't awful, but I think you can go quite a ways on the stock rear if you're auto. Look at Ryan Stevens - he's running low 9s on a stock rear and axles.

[Chris49066SS]

Originally Posted by acammer

For your goals a TH400 or 4L80 swap probably makes a lot of sense. 6L80s can be made to survive big power, but it's expensive and still seems to be a bit of a lottery. Solid axle conversions aren't awful, but I think you can go quite a ways on the stock rear if you're auto. Look at Ryan Stevens - he's running low 9s on a stock rear and axles.

Yeah its actually really amazing how thats working for him, and its definitely inspiring. Whats really nice about his setup is that he crosses the line in 3rd and the thing is screaming in what sounds like high 7s. Mine goes into 4th around 95, so I don't have that RPM advantage with this tranny. What driveshaft do you use?

[acammer]

Originally Posted by Chris49066SS

Yeah its actually really amazing how thats working for him, and its definitely inspiring. Whats really nice about his setup is that he crosses the line in 3rd and the thing is screaming in what sounds like high 7s. Mine goes into 4th around 95, so I don't have that RPM advantage with this tranny. What driveshaft do you use?

I have a stock driveshaft in mine for now. I'm sure that, just like anything from the flywheel back, is probably on borrowed time in an M6 car that get's tracked aggressively.

I think he traps at like 7800rpm. He's got the setup to take full advantage of that. I would think at 120 with a locked converter you should be trapping around 6300 - not awful, but not perfectly ideal. A 26" tire would get you to 7000rpm which would be pretty awesome. 4.10s would be good for about 6600rpm. Tire size would be a much easier change than the gear, then you can go back to the 28.8" tall tire as it get's faster and needs more MPH.

[Chris49066SS]

Originally Posted by acammer

I have a stock driveshaft in mine for now. I'm sure that, just like anything from the flywheel back, is probably on borrowed time in an M6 car that get's tracked aggressively.

I think he traps at like 7800rpm. He's got the setup to take full advantage of that. I would think at 120 with a locked converter you should be trapping around 6300 - not awful, but not perfectly ideal. A 26" tire would get you to 7000rpm which would be pretty awesome. 4.10s would be good for about 6600rpm. Tire size would be a much easier change than the gear, then you can go back to the 28.8" tall tire as it get's faster and needs more MPH.

I'm not seeing any 18's that are that short, and even if they were, I'd lose most of my sidewall. I am contemplating what a 15" setup with a 26" tall tire would be like. I'd have more sidewall to part with at that point, and then would have the advantage of the 26" tall. What would the rpms be crossing the line with the 26" and 4.10 gears?

[acammer]

Originally Posted by Chris49066SS

I'm not seeing any 18's that are that short, and even if they were, I'd lose most of my sidewall. I am contemplating what a 15" setup with a 26" tall tire would be like. I'd have more sidewall to part with at that point, and then would have the advantage of the 26" tall. What would the rpms be crossing the line with the 26" and 4.10 gears?

This is a good calculator you can use to play around with gear ratios and tires sizes when you're considering your options. With 4.10's and a 26" tire you'd cross through the beams at 7300rpm at 120mph. More like though, it would probably pick up a few mph with that much more ratio and trap a few mph high, with even more rpm. There are limits to how far you want to with that.

I would consider doing EITHER a shorter tire or a 4.10 with the build you have now and see how it responds to that. Both is going to be pretty extreme, most 6L80 NA guys run a 3.91 because the 4.10 has them shifting into 5th right at the strip. If you can manage your shift points and tune-up you can avoid that, as long as you're still within an RPM at which you trust your valve-train. I sent my stock lifters to 7300rpm routinely with BTR platinum springs and bushed trunions.

A 315/30/18 is a 25.4" diameter tire. You're correct, it does't leave much for a sidewall. A better option is a 275/40/17, which is a 25.7" tire and has a little more sidewall to offer. A 275/50/15 would be a 25.8" tire, and offer you more sidewall still. Lots of different way to accomplish things. What suits you best really depends on your setup. I would think at your current power level you'd be just fine a 17 or 18 - there are guys cutting really good 60' times with setups like that.

[Chris49066SS]

Originally Posted by acammer

This is a good calculator you can use to play around with gear ratios and tires sizes when you're considering your options. With 4.10's and a 26" tire you'd cross through the beams at 7300rpm at 120mph. More like though, it would probably pick up a few mph with that much more ratio and trap a few mph high, with even more rpm. There are limits to how far you want to with that.

I would consider doing EITHER a shorter tire or a 4.10 with the build you have now and see how it responds to that. Both is going to be pretty extreme, most 6L80 NA guys run a 3.91 because the 4.10 has them shifting into 5th right at the strip. If you can manage your shift points and tune-up you can avoid that, as long as you're still within an RPM at which you trust your valve-train. I sent my stock lifters to 7300rpm routinely with BTR platinum springs and bushed trunions.

A 315/30/18 is a 25.4" diameter tire. You're correct, it does't leave much for a sidewall. A better option is a 275/40/17, which is a 25.7" tire and has a little more sidewall to offer. A 275/50/15 would be a 25.8" tire, and offer you more sidewall still. Lots of different way to accomplish things. What suits you best really depends on your setup. I would think at your current power level you'd be just fine a 17 or 18 - there are guys cutting really good 60' times with setups like that.

Thanks for the calculator, I was starting to think you were writing out huge equations at a chalkboard! Thank you for the tire references too, its going to help out a lot when I am getting my parts. I trust my valvetrain is up to the task. I'll get CHE trunnions and Johnson lifters later on, probably at the same time I go to E85.

[sixty9fordkiller]

Originally Posted by acammer

Sheesh - I went 12.59@113.49 on similar mods to your 12.12 pass - that's total instanity. What was the trap speed for that pass?

11.87@116 is madness with bolt ons. What was the 60' time like? You got some weight out of the car?

That's really impressive work. Most bolt on cars I see are lucky to run mid 12's. I'll be happy if I can run some mid 11's with the cam only set. I'm full weight, and not the lightest jockey in the stable either.

But yea, that final drive ratio is EVERYTHING to a big heavy car like this. Totally under-appreciated thing. I die every time I see somebody talk about adding 3.91's to an M6 car - I'm like JUST GO 4.10 - no downsides and a lot to be gained.

12.12 pass - that's total instanity. What was the trap speed for that pass?
114mph.

Also, had front passenger seat removed and no air compressor in the trunk. just over 1 gallon of gas in the tank. Michelin pilot sport rear tires. factory size. factory wheels all the way around.

Believe it or not, the MBRP aftermarket catback served as a weight reduction. The stock catback is heavey as hell

my 11.87 pass had a lot to do with the 26" tire diameter and the light ass wheels my friend let me use. Bogarts. 17x5 fronts and 17x10 rears. WAYYYYY lighter than the factory 20" wheel.

[Chris49066SS]

Originally Posted by sixty9fordkiller

12.12 pass - that's total instanity. What was the trap speed for that pass?
114mph.

Also, had front passenger seat removed and no air compressor in the trunk. just over 1 gallon of gas in the tank. Michelin pilot sport rear tires. factory size. factory wheels all the way around.

Believe it or not, the MBRP aftermarket catback served as a weight reduction. The stock catback is heavey as hell

my 11.87 pass had a lot to do with the 26" tire diameter and the light ass wheels my friend let me use. Bogarts. 17x5 fronts and 17x10 rears. WAYYYYY lighter than the factory 20" wheel.

Are you able to unbolt your exhaust at the headers, and if so, have you considered running open headers for the strip, then bolting it up again for any daily driving? Depending on your catback, that could be a nice little chunk in weight reduction.