Cam Selection Help
 

NEED HELP SELECTING NEW CAM!!

I'm looking to replace a hydraulic lifter (comp cam 11-236-4) with a hydraulic roller. Any ideas???

mercury marine 454
10.5 : 1 compession
performer RPM intake
750 Rochester quadrajet
crane gold roller rockers
Stock exhaust manifolds
cast oval port heads

Im currently looking at a comp cam 11-451-8
547/547 lift
284/290 duration
112 lobe
110 intake

Would there be a problem with water reversion, with the stock exhaust manifolds??

Would the block need to be modified to accomodate roller lifters???

ANY SUGGESTIONS WOULD BE APPRECIATED!!!

You should seriously consider an exhaust upgrade first. If you are talking stock cast iron exhaust, any cam other than close to stock will revert water.

Next, ditch the Q jet and go with a Holley or Sea Demon 800cfm.

Upgrade the cam to something close to a Crane 168731
http://store.summitracing.com/partde...1&autoview=sku

The block does not need to be modified. You have to use retrofit lifters, valve springs matched to the cam and a different timing chain.

The 168731 by Crane is very very close to the Hp500 EFI cam and I have one for sale with lifters Dyno time only $450.00 plus shipping.

A great person to contact would be "RMBUILDER"/Bob Madara of Marine Kinetics in N.Y. 585-654-8583. He is the cam guru and will custom grind a cam specifically for YOUR application and what you want the engine to do. He has helped hundreds on guys here on OSO and other websites....including me with my own engines.

You need to do the exhaust upgrade before you do the cam. You will not see big gains if you only do the exhaust but it will be needed with a performance build. If I had to do it over I would have done it that way.