I have a 302 in my mav and have been running 15.2 89 mph with bad 60 ft. times due to wheel spin currently running 2.79 gears. I am getting street slicks (hopefully shorter tire and better traction)and changing my gears to 3.40 how Much of a change should I expect on my ET and MPH???
is this a posi. 3.40 ? if the motor can handle the extra tq. it will be a plus. if it bogs then it will be a neg. effect. some situations you need a little spin. JMO from a nonracer... ......
Absorb what my friend Frank has to say ..... then throw it out the window (Just kiddin' my friend Frank! I miss ya, Pal.) From what little experience I have watching other racers (much more than racing my own cars), the MPH won't change that much, as mph relates to the amount of horsepower (generally speaking). For example: you could spend the first 10' spinning for 30 seconds. But once the tires grab, however, you are still going to accelerate and cross the traps at only slightly less MPH as if you'd hooked up nicely. You haven't changed the amount of horses - only the gearing and traction. Before someone jumps on me - yes, there will be a difference - but not that much. It's hard to guess what you're 60' would be not knowing what your 60' is without spinning. However, I ga-ron-tee your 60' will drop if you have slicks and a taller gear. The slicks will ALWAYS hook up at your power level. A lot also depends on your stall converter or what rpm you're launching at. Assuming you have a 1800-2000ish stall converter, are able to get traction (which you will using slicks), and your carb doesn't load up now that the engine r's aren't up as much as if you were spinning which would burn the extra fuel, I'd say you could probably count on a .15 to .20 quicker 60' - which could equate to about .3 to .4 quicker e.t. at the end of a quarter mile (less in the 1/8th, obviously). Good luck and let us know what the "real world" numbers are please. It'll be good data.
just my 2 cents but i don't think your going to see much difference changing from 2.79 to 3.40. the slicks will help a little, but i don't think you'll see much more mph. if any. then again, i was wrong once before.
I just switched from a 3.00 open rear to a 3.55 detroit locker and added drag radials. I'm going to the track this Friday night and see what the difference is. Of course, I'm just running a 250 I6 but it will be interesting to see what the difference is.
That sounds good to me 2. Not much addtional MPH, but a good ET boost from gears and traction. I had 3.00 gears with no traction and a cam that didn't start until 2500 rpm, so I had to spin 2.5 second 60' times or the car would fall flat on it's face and bog big time. When I put 4.11 gears, I never got it back to the track, but I KNOW the car was SO much faster! The engine was in it's 'happy range' all the time. No bog, just major wheel spin in all 4 gears. (25" tall radials!)
What the? Ran the Maverick last night and not only did it not run any quicker, it ran .5 slower than my best time to date! I'm beside myself right now trying to figure out why this would happen. Granted, I went from 14 inch rims with P195-75R-14 stock tires to 15 inch rims and the drag radials 235-60R-15 ( 26 X 8 ). By formula, the stock tires come out to about 25.5 inches tall and the drag radials 26.1 inches. In comparing the two side by side it looks more like about 1 inch difference. If anything I should at least be running the same times, I would think, although I was expecting much better. 60 foot times were better compared to similar et's before the changes and mph was only down about 1 mph. Is the tire just too much for my nearly stock I6? :confused:
I have found more gear is usually not so good with a stock engine. Granted, 3.55s and taller tires are not too steep. If you don't extend the rpm capabilities of the engine when you do lower gears, they can truncate your rpm/power range to a shorter usable period.
one thing to remember gene is that the stickier tire takes more power to move it. like i said in my above post, i didn't think you would see any more mph. hopefully it is more consistent though.
14.7-14.8.If you hook it up you'll actually run less mph,when you were spinning your mph was getting a head start.At least my timeslips read that way.
