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Author Topic:   power differences
TNT-Mod
Dirt Roller

Total posts: 8
posted May 25, 2005 11:09 AM  
Ok guys Im running on a very high banked 4/10 mile track. I am getting DRILLED down the straight away. on the starts and some laps the fast guys are pulling me as much as 5 car lengths or more. Im running a decent 355 right now on gas. My question is how much would going to a 383 help me? and also how much would going to alky help me. Im getting killed the first half of the straight but everyone says it looks like i latch on for the last half. The problem isnt wheel spin because if anything Im bogging down coming off the corners while the fast guys are hauling @$$.

Dman
Dirt Freak

Total posts: 270
posted May 25, 2005 11:16 AM  
It may be you are out cubed but you may be over cammed.We don't get pulled when we run our 355 on a tacky track.We run the Midwest motorsports cams recomended by MWMS for our track/car/weight and gear specs.Good Luck!

wfoondirt
Dirt Forum Champ
Total posts: 505
posted May 25, 2005 12:17 PM  
More gear or different cam.

TNT-Mod
Dirt Roller

Total posts: 8
posted May 25, 2005 01:26 PM  
thanks guys for your responses guys. My engine builder seemed to think its a gearing problem. But i couldnt help but to want some 2nd opinions..lol Here is where the problem lies. I have JE pistons, but I have the vortec rods and stock crank. So im afraid to turn the thing over 7000. Usually the motor turns around 67 to 6800. Im figuring that if i do anything to increase the power id be a fool to not put a really good rotating assembly in it. And a 383 rotating assmbly cost just as much as a 355. Im running against some Big engines and Im getting pulled about 5 to 7 car lengths off of every corner. They seem to quit pulling away from me after we get past the flag stand. How much would switching to alky help?

ratracer10
Dirt Maniac

Total posts: 141
posted May 25, 2005 01:39 PM  
Just out of curiosity, how soon are you able to get to full throttle?

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- When in doubt, hit the gas.

spde
Dirt Freak

Total posts: 243
posted May 25, 2005 02:34 PM  
you need 14.0 to 1 comp for alky to help. anything less it will be a wash. i would try a gear 1st. make sure you are in the power range for your cam. this sould be a 300-400 rpm over the low limit. next a cam i switched to a reed cam this year, a different motor now! hope this helps. gl ltr

Panky AMCA 21
Dirt Roller

Total posts: 11
posted May 25, 2005 07:52 PM  
If you are worried about gearing, you could advance your cam timing a couple of degrees which would bring the rev range of your cam in earlier, a trade off would less at end of straight but if you can find the happy medium it might help

andykmod
Dirt Freak

Total posts: 351
posted May 25, 2005 07:53 PM  
More gear. I turn a 355 with stock rods and cranks with speedpro pistons 7200 no problems yet! More cubes would not hurt though.

dirtzone
Dirt Maniac

Total posts: 102
posted May 26, 2005 04:12 AM  
Just make sure your carb isn't too big or running too rich or you'll be boggin off the corner. Also if you run power valves in your carb, make sure these are still good or it will do the same. Other than checking your initial timing is set, I'd have to agree: gear or advance the cam.

graham jackson
Dirt Full Roller

Total posts: 42
posted May 26, 2005 05:20 AM  
We run a 355 also and you can get a lot out of them and run with a lot of big motors.
GEAR for sure you need more gear. Also what is your current cam at .050 ? This will tell you a lot about the low end.

Also if you are running this weekend, try opening the valves up for more low end. I dont know what your lash is at know but I would open them up to as much a 0.30 to get more low end. If this helps but is not enough then you may need a cam change as mentioned.

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