Originally Posted by Timox (Post 11899457)

I have a Plus 4BTT that's seems to always want to run hot and am not sure why ? It wants to always run at 275 with not even a race tune on it yet and too me that seems a bit hot ?

It has about 0.8 gallons through it now. Its been rebuilt with a new piston/sleeve/rod and bearings. Changed the carb out with another Novarossi one i had and still the same result.

Car is new MBX7 and drive train spins free as can be. Its also been made light at 3240g so its not like the engine is having to work hard to push it.

Engine has lost its metal pinch at TDC also. No air leaks in the fuel system.

I just don't know what it could be. Its blowing a nice thick smoke trail all the way from bottom to top end..... ?

Any ideas ? If i try to really race tune it it just gets even hotter pushing 300. But if i ritchen it i loose top end and power and run time.

Originally Posted by Timox (Post 11899457)

I have a Plus 4BTT that's seems to always want to run hot and am not sure why ? It wants to always run at 275 with not even a race tune on it yet and too me that seems a bit hot ?

It has about 0.8 gallons through it now. Its been rebuilt with a new piston/sleeve/rod and bearings. Changed the carb out with another Novarossi one i had and still the same result.

Car is new MBX7 and drive train spins free as can be. Its also been made light at 3240g so its not like the engine is having to work hard to push it.

Engine has lost its metal pinch at TDC also. No air leaks in the fuel system.

I just don't know what it could be. Its blowing a nice thick smoke trail all the way from bottom to top end..... ?

Any ideas ? If i try to really race tune it it just gets even hotter pushing 300. But if i ritchen it i loose top end and power and run time.

Originally Posted by aznitronut (Post 11899998)

Monty, how good is fuel economy on the Nova Roma .25? In Truggy.

Originally Posted by Maximo (Post 11899943)

Can you get more airlfow over the head ? or thru the head ? these new low profile Nova's tend to get buried under the body and not get proper airflow thru them..... These are air cooled engines and they will run hot if you don't have proper airflow ....Low profile heads tend to not get as much airflow and will run hotter....... Increase the airflow and you should see a reduction in temperature....

Originally Posted by andy733 (Post 11907477)

looking to buy a new engine and have decided on these two but would like to know which one is better for a buggy

thanks
andrew

Originally Posted by Z-Man. (Post 11910116)

Can anyone tell me the Btta rear bearing size?

thanks