Visit The Dirt Forum for More Information

Author Topic:   hobby jetting?
Dirt Full Roller

Total posts: 33
posted September 07, 2005 08:20 PM  
i am racing a hobby stock and have been over heating and an wondering if maybe its not jetted right. carb is a roscester carb from speedway motors. carb has 76's in it .Also when i am in the gas there is a blue flame coming out of the exhaust. motor is a 350 any help would be great timing is set at 36 degrees thanks

Dirt Forum Champ
Total posts: 5390
posted September 08, 2005 04:16 PM  
I"ll have to check them out and get back to ya. whats a good starting place for the jets? any more help would be great thanks

Dirt Forum Champ
Total posts: 784
posted September 08, 2005 07:29 PM  
the motor i run is a 9to1 350 with a speedway cam #2 pump fuel 2 barrel intake

Dirt Freak

Total posts: 333
posted September 09, 2005 12:44 PM  
Jetting plays a part in how hot your engine will run, but I'd start looking elsewhere for over heating problems. You didn't say HOW much you are over heating. Maybe you really are not. Are you over 220 - 230 degrees while running (full out) during the race? How's the weather in your location? Humid, really hot temps, ect. I know my car will get up to 230 when parading during a caution, but generally the engine does not get over 205 during a blistering pace full throttle race lap after lap.

Run a solid steel fan, (I run a 5 blade, but some prefer a 4 or 6 blade)

Make sure all incoming air is concentrated into the radiator and then pulled by the fan into the engine, no leaking or sucking around the shroud.

Check your pulley ratio.

If your using a thermostat or restrictor plate (washer) make sure it is the right size and working. I run a 7/8" restrictor.

Recently I was running about 15 degrees hotter than normal, and after pulling the heads we found the head gasket was blown between two cylinders. Water was going into an one cylinder and burning out the exhaust with no signs on plug, outside of head, ect. We were just loosing water.

Sorry about running on here, just trying to add a little insight to other areas to look at.

Good luck, and Race on.

(Wish I was at Boone right now. I miss it!!!)

if it ain't fun, then don't run

A. Bighurry
Dirt Full Roller

Total posts: 35
posted September 21, 2005 08:04 PM  
You might check your timing. Lazy ignition timing will cause similar problems.


Back to the Archives