m/t sportsman tire heigth

[340 mopar]

what size tire should i run? i can fit 29/12.5/15. mini tubbed. about 450hp i think. 1970 scamp, 3500lbs,340- 10/5 to 1, pop-up hyperu, closed chambered heads (thick gasket) air gap intake, 750dp, lunati solid cam 60433, ported heads from brian. shift at 6700 to 7000. 430 posi 8 3/4, 727 reverse body, 4000 stall (brakes only) do not want to go under 11.5 or i need rollbar.
Thanksrayer:

 

[tubbedamx]

...i can fit 29/12.5/15. mini tubbed...

Thats what you should run

 

[340 mopar]

I want to go through traps at 6700 to 7000 rpms. Where do you think the 29 inch tire will put me at rpms

 

[OldmanRick]

I want to go through traps at 6700 to 7000 rpms. Where do you think the 29 inch tire will put me at rpms

4.30 gear and 29.0 tire and 67-7000 r's puts you at 135-140 mph. I seriously doubt you have the engine for that. 135mph in the 1/4 is equivalent to a 9.80et..........In my opinion you'll need a shorter tire and more gear............or a throttle stop....lol.

To run 11.5 which should be around 116mph and to clear the traps at 67-7000 you need a 5.13 gear with the 29's and a 4.56 with a 26.0" tire.

Also, with the 29" tire and 4.30 gear at 116.0mph with a little conv slip you would go thru at 59-6000 rpm's.

My advice is to run it as is and get some data (incremental numbers and mph) and decide what you need after that.

 

[Abodybomber]

Ask someone to measure please.I ran 2 sets of 29/12.5 /15,on a 15 by 8 ansen slot.Both measuned between 27 to 27.5 tall,aired up properly.This was on an El Camino. As for the 11.50 gig,just roll it out of the hole.Learn the car.

 

[OldmanRick]

Ask someone to measure please.I ran 2 sets of 29/12.5 /15,on a 15 by 8 ansen slot.Both measuned between 27 to 27.5 tall,aired up properly.This was on an El Camino. As for the 11.50 gig,just roll it out of the hole.Learn the car.

That's true, most don't measure there exact rating. Just have to be careful, because the lower radius on a soft wrinkle tire is less at rest and at speed they will grow a hair.

 

[flyfish]

With that tire you will have no problem running slower than 11.5 (Not very good grip at the track).

For what it's worth, on my old 360 combo I went from running 12.1 @ 116mph on the Micky Thompson sportsman pros, to 11.5 @ 116mph running a Hoosier quick time pro...no other changes, just tires.

 

[MoparAnglia]

4.30 gear and 29.0 tire and 67-7000 r's puts you at 135-140 mph. I seriously doubt you have the engine for that. 135mph in the 1/4 is equivalent to a 9.80et..........In my opinion you'll need a shorter tire and more gear............or a throttle stop....lol.

To run 11.5 which should be around 116mph and to clear the traps at 67-7000 you need a 5.13 gear with the 29's and a 4.56 with a 26.0" tire.

Also, with the 29" tire and 4.30 gear at 116.0mph with a little conv slip you would go thru at 59-6000 rpm's.

My advice is to run it as is and get some data (incremental numbers and mph) and decide what you need after that.

The maths may tell you that but it will not happen. Converter slippage will seriously dent that equation.

 

[MoparAnglia]

With that tire you will have no problem running slower than 11.5 (Not very good grip at the track).

For what it's worth, on my old 360 combo I went from running 12.1 @ 116mph on the Micky Thompson sportsman pros, to 11.5 @ 116mph running a Hoosier quick time pro...no other changes, just tires.

We have the world's quickest Sportsman Pro tyre'd street cars over here (pump gas, full exhausts too) down into 7.6s in the quarter with 60 foot times in the 1.2s. The big MTs (31s and 33s) can provide plenty of grip with the right chassis set-up to suit them.

 

[OldmanRick]

The OP has Sportsman in his title. Several of my bud's made the mistake of not buying "Pro's". I've seen the Pro's work well, but the regular Sportman's are all show and no go.......

 

[flyfish]

We have the world's quickest Sportsman Pro tyre'd street cars over here (pump gas, full exhausts too) down into 7.6s in the quarter with 60 foot times in the 1.2s. The big MTs (31s and 33s) can provide plenty of grip with the right chassis set-up to suit them.

Yeah, with a 4 link and those big-ole steam rollers (33's) you could probably hook up in a car wash. I was using stock suspension (leaf springs) and 26" tall sportsman pro's, the Hoosier QTP were 27".

For the OP: I'm currently running the 11.5 x 28" Hoosier QTP's, and they fit nicely in my mini-tubbed Barracuda. I have herd that some people can fit a 29" tall tire...but it is tight.

 

[a1090cuda]

For what it's worth here's my combo, and what it runs.

MT 29.5 x 10.5w x 15 slick
4.56 gears
10.60's @ 124
Between 6980 and 7075 through the lights. It's automatic on every pass, unless something has happened out of the ordinary. When on the stop it verys depending on what program I'm running. Just my .02