I have a brand new set of Crane Energizer Roller rockers 1.5. I thinking about buy a set of the Comp Cams Magnum Roller Rocker and get the 1.6. I have already measured my pushrod length and it's 7.800, How much will the 1.6 roller rocker affect my pushrod geometery?
Second is it worth to upgrade to the magnum on a street hp engine.
Solid Cam
247/251@.050
Gross Valve Lift Intake 0.518 w/1.5:1 Rockers
Gross Valve Lift Intake 0.552 w/1.6:1 Rockers
Gross Valve Lift Exhaust 0.530 w/1.5:1 Rockers
Gross Valve Lift Exhaust 0.565 w/1.6:1 Rockers

Lash Recommendation is .026

Net Valve Lift Intake 0.495 w/1.5:1 Rockers
Net Valve Lift Intake 0.526 w/1.6:1 Rockers
Net Valve Lift Exhaust 0.504 w/1.5:1 Rockers
Net Valve Lift Exhaust 0.539 w/1.6:1 Rockers

The AFR 195 flow numbers at .500-.550 @260-262 I think the 1.6 ratio will be the best to max the efficiency of the heads.
What are your opinions?

are you talking magnum or pro-magnum?

Here is what I want if its beneficial on the street.
CCA-1302-16 1.6 ratio, 3/8 in. rocker arm studs, chromemoly steel, Pro Magnum, roller, rocker arms

i just swapped from some pro magnum 1.5s to their stainless steel heavier body 1.6s roller rockers. i have afr 195s as well, and my cams lift with 1.5s net was .485 /.494 and with 1.6s it was .518 /.527

even with the heavier bodied rocker i picked up .06-.07 and 1 mph. it was a little hotter by about 10* that day than my previous best, so it definitely helped.

You should get a 1/2-1/2 set of 1.5 and 1.6's. 1.6 on the intake is the best combo. 1.6's on the exhaust usually cost power. I have Pro Magnums 1.6 on my intakes and Harland Sharp 1.5 on the exhaust. Pushrods are different lenghts, .100 long on the intakes and .100" short on the exhaust. That's what it took to get the right geometry.

FYI I have the SB chromemoly Pro Magnums for $265 ($275 for BB) to your door, no shipping or handling charges, in the lower 48 states. SB in 1.52 or 1.6 ratio either 3/8" or 7/16" stud. BB 1.7 ratio 7/16" stud. Tons of other engine stuff cheap too! :D

Does anyone know of a company that will sell 8 of each of the PROMAGNUMS? Some places sell the individually, but the price is usually $25 for one.

MaTt

Originally posted by Pat Kelley:
You should get a 1/2-1/2 set of 1.5 and 1.6's. 1.6 on the intake is the best combo. 1.6's on the exhaust usually cost power. I have Pro Magnums 1.6 on my intakes and Harland Sharp 1.5 on the exhaust. Pushrods are different lenghts, .100 long on the intakes and .100" short on the exhaust. That's what it took to get the right geometry. How much does swapping to a 1.6 roller, pushing cam lift to over .500", affect your valvesprings if your valve springs are rated for nothing over a .500" lift? Would you need to swap in stronger valve springs? Or would you be better off leaving your rollers at 1.5?

You do need to check for coil bind, also that the pushrod clears the opening in the head. I spend some 2 hours on my Sportsman II heads with a die grinder clearencing 8 holes.

Matt, call Comp and see if you can get a part number. Mixed set are very common in the racing world vs the street world.

Originally posted by Mz28att:
Does anyone know of a company that will sell 8 of each of the PROMAGNUMS? Some places sell the individually, but the price is usually $25 for one.MaTt The best thing to do is find someone else interested in using the 1.5/1.6 setup and each of you buy a set from Oldani Motorsports and have him split the set and mail them out with 8ea-1.5 and 8ea.-1.6 each. Plus Free Shipping graemlins/hurray.gif :D graemlins/thumbsup.gif

When I built my 383 SBC, I bought a full set (16) of 1.6 Pro Magnums and (8) individual packaged 1.52 ratio rockers.
Then just sold the (8) 1.6 rockers that weren't needed on Ebay...easily!
$20 each...MORE than what I had paid. ;)