Thread: 13.'s with a roller cam?

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I currently have a 350 with cast sportsman II 2.02/1.60 heads, performer intake, 4.70 lift, 226 dur @.05 (3/4 race) cam, holley 600 carb, headers, and 9.5:1 compression all good for about 370 hp@5500rpm. TH350 w/ shift kit and 3000 stall converter, out back i have a 12 bolt posi with 3.31's and j-bolt traction bars. It pulls 14.5's in the 1/4 mile. My question is what i could do to put me in the 13's. I want to convert to a roller cam with a little more bump and put a performer rpm airgap with a holley 670 avenger carb. This will put me at around 410 to 425 hp im guessin. Problem is that my bottom end of the 350 is completely stock. Crank, rods, pistons. Will this hold up to about the 6100 rpm the roller will need? will this upgrade put me in the 13's? what other tricks can i use to lower my 1/4 mile time? Any comments help. Thanks!!

Doesn't sound like enough gear. What RPM are you turning at the end of the quarter????

im not too sure but im guessin about 4600-4800 rpm

Next time take a look at the tach and see what the RPM is at the end of the quarter.....with that motor and the right gears it should allready be in the 13's......

actually more like 4200-4400 rpm. sorry

i went to a gear calculator and put in the trap speed of about 97mph with 3.31's and it gave me 4200 rpm. I also didnt mention that i have radial t/a's at about 25 lb's of pressure and i do get a little tire spin off the line.

get a better set of tire and work on the 60 foot .try set of bf drag radials tires

were the power is at cam, heads , intake , and compression

I think the car should be in the 13's as is. You may have a healthy enough of a 350 to graduate to a bigger carb. I'm running a 15.4 at 88mph in a truck with 29.6" tires, a 3.07 gear, a stock converter, a stock qjet carb, and stock hei ignition. If I went to a 3.73 or 4.11 gear, I could probably be deep in the 14's. My motor is a lot more conservative with only 212 degrees of duration at .050" and .447 lift overall for the cam and 9.25:1 compression. My best 60' was a 2.318. A performer RPM intake for you will probably match the cam a little better as well.

The move to the 670 is the right move, but I think I would change that rear gear to 355's. Your WAY too low in rpm's to be hitting the traps at 4200 RPM. I would even consider trying a 750 cfm holley for a couple of passes with the cam you have before I went changing it out. You should be hitting the traps at about 6200 to be getting all of the power band, and your strangling those heads with the small carb.
No flow- no go....just a thought................Jim

i agree with you on the gears. The 12 bolt was off a 68 camaro with stock 3.31's. Ill probably upgrade to a set of performance 3.55's or 3.73's soon. Also still wanted to know if a stock bottom end can hack the 6100 rpms? Thanks!

Yes it will handle 6200 rpm easy.

Originally posted by 70_"SuperNOVA"
i agree with you on the gears. The 12 bolt was off a 68 camaro with stock 3.31's. Ill probably upgrade to a set of performance 3.55's or 3.73's soon. Also still wanted to know if a stock bottom end can hack the 6100 rpms? Thanks!

yes more gear will help BUT if it spin now all you will do is spin more make this run faster carb gear and cam more stall more rpm and on the bottom end if done rigth it should take 6500

Drop your air to 12 lbs in the rear tires.......

why not try a set of bf drag radial tires? soft tires hook lot better than 10 psi in stock raidials ??