[2fast4d]

First post on new site, looks great!!!!!!!!!!!!!!!!!! I was wondering if any body could help me with a valve lift question. I am putting together a 460 for mostly drag use some street. The motor currently has a set of d3ve giving me a little over 10:1 with domed pistons. Thinking of going with more cam for this summer, cam is a 585 lift exhaust and 585 lift intake 253/253 @.50. I will be spraying the motor two stage around 250 total. I have not ran the combo yet, just wanting to get it right the first time. What is the best way to check for the max valve lift to piston clearance problems. Any suggestions on a cam or does any one have anything for sale. I also have a set of c8ve heads, but am concerned the compression would be to much for street use, and i only have a 850cfm carb. Any info would be great, could not figure out how to post pics[/img]

 

[rmcomprandy]

Nitrous is a TORQUE maker not nessessarily upper rpm horsepower so, leave the compression ratio alone but, use a cam with 12 to 14 degrees MORE exhaust duration, (about 256*/268* for sometimes street engine), and keep the seperation wide to cut down the overlap; if you can find a used one or a new one is totally up to you.
You gotta let that extra exhaust out in order to see the best benefits.

 

[2fast4d]

Lift?

Any suggestions of valve lift, and best way to check for clearance. Or will i not be able to support much more with a 850 cfm carb.

 

[Jon]

answers

Max valve lift is not when it is the closest to the piston. You need to put some light checker springs on the heads and rotate the motor 5 degrees at a time checking the distance to the piston with a dial indicator. You need a split duration cam. You can run 10.0 to 1 as long as you have good quench and decent gas. 850 cfm is fine for the street.