help with rpm

[Bnice]

have a 355 sbc hei 65,000 volt kmj dis. 4412 2bl. 640/642 lift roller cam bowtie 64 cc angle plug heads 2v intake 14 to 1 comp.6in rod running 600 gear 3000 lbs car running on a LARGE 3/8 mile track wide corners same gear as everyone else cant get over 5000 rpm sound great runs good no pull down straightaway???????

[rubbinsracin]

that little of carb probably doesnt help. what are you jetted at in your carb?

[raceman17]

What cam is in the motor? You may need to add more gear also.

You should have no problem turning 6500-7000 rpm on that size track. We do it every weekend with a .500 lift hydralic cam, vortec heads, and a 4412.

How old are the valve springs? Are you floating the valves? Is the motor breaking down any? What kind of transmission?

[Bnice]

cam is like 296 304 640 645 and i have ran carb and same gear at smaller track same bottom end and heads an ran 7800 heads are all new valves and springs set at 215# do u yhink cam deg would make a 2500 rpm diff couse i should be running 7500 like always did before with basic same set up has no miss sound great plug reading is good ????????????????

[Egoracing]

Make sure the carb butterflies are opening all the way and/or not over centering and starting to close the openings.

[Bnice]

yes carb is fine even had a new 4bl same rpm the vacume adv.was locked in dis. but was done by well back yard guy and its all the way back looked at a aftermarket lock and its in middle could this b problem

[raceman17]

Did you go back and set the timing after you added the aftermarket lockout for the vaccuum advance? It should not matter where the advance is locked out as long as you go back and set the timing.

[Bnice]

set timeing at 38 deg will run car sat and see what we come up with let u know

[Bnice]

set timing at 38 deg will run car sat and see what we come up with let u know