[68birdfreak]

Well...anybody wanna take a stab at what the new ET's will be vs. old radial street tires? I went with 26 x 11.50 X 15's . old tires were 27.2 inches tall with ZERO traction. New ones are Mickey Thompson et streets. Current best is a 12.54 at 113 with a 1.98 60 ft....give or take. I would like to see 11.99... anybody think it is possible?

[BILTIT]

Yes, be prepared to hook! What rear gear?

[71 Ventura II]

If you can get the 60' down to a 1.79 it will pull off a 12.19 @111.0-112.7 MPH. Notice the slight MPH loss, this is from the "Lugging" force the car will experience with traction! Anything quicker than this will require a much better 60' time, which will depend on the suspension and the willingness of the driver to launch it hard. Good LUCK! JD

P.S. If you could maintain the same MPH with everything remaining the same you would need roughly a 1.67 60' time to crack the 11.99

[68birdfreak]

Originally Posted by 71 Ventura II

If you can get the 60' down to a 1.79 it will pull off a 12.19 @111.0-112.7 MPH. Notice the slight MPH loss, this is from the "Lugging" force the car will experience with traction! Anything quicker than this will require a much better 60' time, which will depend on the suspension and the willingness of the driver to launch it hard. Good LUCK! JD

P.S. If you could maintain the same MPH with everything remaining the same you would need roughly a 1.67 60' time to crack the 11.99

Cool..thanks for the info! I am gonna start at a 2500rpm launch and go up in 500 rpm increments till the tires break ...

[BILTIT]

Tires or the diff/driveshaft?

[68birdfreak]

Rear end is a new moser 12 bolt with 35 spline axles and diff is detroit tru trac ....should be ok...the drive shaft is factory with some good u-joints..i thought the drive shafts were good to 600hp...

[TIN TIGR]

run it..no pain no gain..if your gonna pussyfoot it all the time why go to the strip..

[mikeb]

I saw the title of this thread and had to laugh, because i'm going the other way. The latest "hot" thing at our local tracks are "factory rubber shootouts". Rear tires have to be "real" street tires (no drag radials or bogus DOT approvals on an obvious race tire); you can run the biggest meats you can fit under the car. Also, you can run any power adder you want. I think the racing in this class is going to be exciting.

As far as your deal you are going to be shocked at the traction difference.

[70judgeconv]

I twisted my factory driveshaft in
half running low 12.0's. I'll bet 12 teens.

[gold bird]

11.999999

[BVR421]

Originally Posted by 68birdfreak

....should be ok...the drive shaft is factory with some good u-joints..i thought the drive shafts were good to 600hp...

I nominate this quote as best of the day !!!!!!!!

I predict at least 2 tenths drop, you will like it not having to ease into the throttle

[BVR421]

Originally Posted by mikeb

I saw the title of this thread and had to laugh, because i'm going the other way. The latest "hot" thing at our local tracks are "factory rubber shootouts". Rear tires have to be "real" street tires (no drag radials or bogus DOT approvals on an obvious race tire); you can run the biggest meats you can fit under the car. Also, you can run any power adder you want. I think the racing in this class is going to be exciting.

that sounds like really fun racing, keep us updated!

[TCSGTO]

If your car dead hooks you may find you'll need some carb tuning to eliminate any bogs. Tire spin covers up alot of tuning issues. Also try leaving from a dead idle as well as loading up the converter. You may find better 60" times using a lower stage RPM than you think. Above all HAVE FUN!

[BILTIT]

Standard transmissions don't have convertors

[prostreet64]

No substitute for traction! Once you get the launch optimized I am pretty sure you will see those 11's coming up. On the Bird we are still tinkering with the suspension to be able to launch the car up on the converter; as yet the best 60' is 1.63 but the best e.t. was on a 1.66 with a little wheel spin. If you can knock 3 tenths off your 60' you are well on your way. I have a lot of respect for you guys who can make it all happen rowing the gears. Autos take a lot of the guess work out of it. Good luck.

[davsgto]

Rev up the sucker & dump that clutch, chicken ??? It's only parts you'll break. Really, be patient, find your sweet spot. Just make sure something is slipping. Clutch, tires or somethink else WILL break. I,ve launched mine up to 6k & been real lucky to not break something major yet. Just have funnnnnnnnnnnnn.

See Ya
Dave

[Ron H]

I am not sure if you'll see .55 from the swap. But you will find out quick what your weak spot is. The smaller tire will rpm higher so your engine may like it and give you a bit more, or may not.
Good Luck.

[guidos]

Your best bet is to launch at a higher RPM say 4000 but pump your tires up so they spin, then slowly lower them till they just turn a couple of rotations.. If you car dead hooks something will give, maybe not right away but something really needs to slip a little.

Good luck and let us know how you do.......I am hoping for 11's for yeah, but it is a different deal with a stick!!

[stickboy]

So did it hook? Did it break the tires loose or the driveshaft?

[71 Ventura II]

The silence is making me worry like something went wrong or broke. Even if the results were less than expected we can help. Hopefully he is ok. JD