I am wanting to build a drag Maverick. I plan on using my 72 grabber body with 74 disc brakes. My dad has a 77 302 that he will give me. I plan on putting an intake with about a 650 holley carb, a mild cam, MSD ignition, and headers. I want to buy a converter with a 3500 stall speed and put a spool in the rear with 5:43 gears and slicks. This will be an 1/8 mile drag car only. I figured this would be in the high 8's or low 9's in the eighth. I was wondering if I was about right on the et or way off.
I think a lot will also depend on what heads you are using. A good cam and heads will make a world of difference. not sure of the gear but you might run out of power before you get to the end. Maybe someone more used to 1/8 mile racing can give you a heads up on that.
Depending on RPM's , a 4.30 to 5.43 gear will get that! I ran a 4.56 gear 28" tire and ran 7.70's with 5500 across the line. Every inch of height in the tire is 200 rpm so a 5.43 may be ok!
I'm running a 4:10 to 1 in the 1/8th. It shifts into 3rd just before the lights on the big end. As Don said, heads , cam, and headers are the key in the engine department. For what it's worth,,,,
"Mild cam" between 280 and 300 degrees intake duration should match up OK with the stall and gears. Put the car on a diet and a good tune I would think closer to high to mid 7's. Cleaver
that is the same set-up I had with my old 306. I ran the same #'s as well...7.70 @ 86. I was a little closer to 6,000rpm.
my setup in my old car was a 306 with a 4.56 gear. 750 holley, victor jr intake, a set of cleaned up 69 windsor heads with a 3800 converter. it ran a best of 7.17 @ 96 mph. so i think you might be alot faster than you are expecting.
If I did the original setup but bought this set of heads with roller rockers do you think I could get in the high 7's http://www.jegs.com/i/World Products/955/053040-1/10002/-1
W/a '77 302,stock heads & compression?Nahh,he's guessing it pretty close I'd say,but w/a mild cam,stock heads he doesn't need much more than a 4.10 gear.High 8/low 9s should be easily(read-cheap)attainable.BTW,my 75 4dr w/a stock roller 302,Wieand 8011/holley 600,Hedmans 3500 stall 3.55s ran 9.05.W/a borrowed 4.62 gear it ran...9.05,plus it was undriveable.
750 or 650 What camshaft profile did you use? also would the 750 be a better choice than a 650 in upper rpm's?
i have run three different 306 engines all with different cams and they were all close. i have a great custom ground flat tappet from cam motion that was in my last engine for sale. i think it's in the 296 duration range and around 570 lift. it would work best with a steep gear and loose converter though. i would go with the 650 if you keep the mild combo listed in this thread. it will be easier to tune and responsive especially in an 1/8 mile car.
Now being that I'm a 1/4 mile racer, I could be wrong on what I'm about to type. I agree with what greasemonkey said, 5:43 gears are waaaay to low for the motor you are talking about. You are going to run out of motor long before you cross the traps. You would be better off with the 4.56 to 488 range, but as always this is just my .02 Hope this helps. Bossmav
