[sportster]

I figured it was time to take the car to the track to see what the new cam would do. I changed out my old Lunati 515/515 300dur cam for a CC XE274 this spring. Here are the numbers:

R/T .552 .761
60 2.120 1.990
330 6.008 5.651
1/8 9.294 8.712
MPH 73.97 80.63
1000 12.185 11.341
1/4 14.668 13.582
MPH 89.86 100.30

The time on the left was last year and the right is last weekend with the new cam.

The only change was the cam and I ran my slicks at 16psi instead of 10psi. I guess if I would ever actually jet and tune the car with smaller tires (29" now) I might get 13 0's.

I guess bigger is not always better .

 

[BillsCamino]

Drop down to a 268 and you'll be in the 12s!
Obviously, the Lunati was too much cam for your combo. Nice!

 

[MikeN]

Very nice! You are quicker than me by just a skoch. I am going out to Atlanta Dragway tomorrow for one last race this season, hopefully I can pick up a little bit.

 

[sportster]

Mike, looks like we may have similar combos. What cam and gear are you running?

Tom

 

[MikeN]

I have a 355 with 9.5 compression, Dart IE180 heads, and a Comp XE262. I also run a 200-4R with 2000 stall and a 12-bolt with 3.42 gears.

I agree that you will probably go quicker with smaller tires. My car ET's about .15 quicker with my 215-60R15 Kelly street radials than it does with a set of MT Sportsman Pro's, 26x10.5-15. I think the taller tire plus the added rotating weight accounts for the slower ET's. On a good track I can pull a 2.00-2.05 60' with the narrow Kelly tires.