Slick size needed for 70 Charger

[jlatessa]

Hi folks,

Have 440 6 pack in our charger, 727 RMVB w/ 2800 converter (383 Hi-po), 4:10 gear.
Probably close 4000#, dyno'd at 465HP, Peaked at 6200 RPM

Would like to trap at 6200, shift at around 5700.
Our local track is not prepped, to say the least.

Have standard wheel wells and 15X8" rims to use.
Am going to quiz Hoosier on their recommendation for compound,
but need a size that will maximize the car's abilities.

Don't plan on a lot of track time, just to know what it is capable of.

Standard rear suspension with a pinion snubber (I know, I know)

Thanks, Joe

[jlatessa]

Hoosier's recommendation was their #18155, C07 compound at 12-14 PSI.
28-10.3"
Sound right?

This is a bias ply slick and I thought the consensus was radial??

Joe

[c00nhunterjoe]

Rpm will depend on what your trap speed will be. So lets say you dont want to be over 6200 instead. That said with your setup, a 28" tire would trap 6200 at 120 mph and a 26 would trap 111. With your hp i would estimate the 26" tire to be better  at your power level. The 28 would bite better but be a tenth slower. If you put a radial slick on to the same size bias you will pick up .15 to .2 more et. If you go hoosier, dont burn them off, just a light haze is all they need. As to width- depends on your suspension and ability. Im well into the low 10s on a 9 inch wide tire and a 1.4 60'.

[c00nhunterjoe]

To add- i missed the 8" rims. So i wouldnt personally run over a 9" slick on an 8" wheel. I run my 9" tire on a 10" rim.

[jlatessa]

Joe , what is the reasoning for the wider wheel, contact patch?

Thanks, Joe

[c00nhunterjoe]

Contact patch, sidewall stability. 2 ton car on a little tire is critical to get right with big hp. Even on a street car it will make a big difference. I sent you an email last night.

[303 Mopar]

At what hp/tq would it be wise to swap from an 8 3/4 to a Dana with slicks?

[cdr]

At what hp/tq would it be wise to swap from an 8 3/4 to a Dana with slicks?

Any good running engine with a 4 speed, small or big block, I would say REAL 550 hp 600 tq in a heavy car with auto trans, I broke my 8 3/4, never again.

[jlatessa]

c00nhunter, didn't get the email; jlatessa@roadrunner.com

Thanks, Joe

[c00nhunterjoe]

I broke a stock, then 2 upgraded 8 3/4s on a 400 hp 383 with a 4 speed and slicks.

[c00nhunterjoe]

https://youtu.be/cH1rhB8FIkU

400 horsepower, hardened 8.75 axles, drag radials, 4 speed, 4.30s. 2nd set broken.