1st tests on Factory Magnum cylinder heads

[IQ52]

My son and I had a pretty good laugh when we first saw the new iron 360X head a few years ago. Now we've had a real good belly laugh over the factory Magnum head. We have been asked to build a '96 360 for a truck. The plan is to use the stock heads so Cody went to work on them. Using a maximum lift of around .500" lift this is what he developed.

Lift...............stock 1.92 intake................ported 2.02 intake

.100....................64......................................71 cfm
.200...................131....................................143
.300...................182....................................201
.400...................217....................................243
.500...................215....................................260

There is more available in that strange looking intake port, but the effort involved to get for a pickup truck didn't seem worth the effort. Well actually the effort expended was far more than we charged for.

Lots of people would like to have the exhaust flows on the intake side. Never tested the stock exhaust.

Lift.............ported 1.62 exhaust

.100....................59 cfm
.200...................136
.300...................201
.400...................217
.500...................221

 

[RustyRatRod]

Flows like a bitch in heat.

Oh and Rodney says your flow bench is happy. lol

 

[IQ52]

Rodney may be right, we're a pretty happy bunch around here. I'm happy to have a flow bench. Happy that my son is such a good porter. Happy that it looks like the dyno may be up and running this summer. Oh, and remember, the magazine editors laughed themselves silly when we told them we would make 100 HP more than any of the other 451 strokers in the dyno contest. It turned out to be 135 HP more than the others. Who's happy now?

 

[RustyRatRod]

Yeah. Whenever he says that...and he does a lot, I just pull up the Duster video. LOL You caint argue with dyno numbers.

 

[RustyRatRod]

Oh, and remember, the magazine editors laughed themselves silly when we told them we would make 100 HP more than any of the other 451 strokers in the dyno contest. It turned out to be 135 HP more than the others. Who's happy now?

But Jim, what I've always wondered was, how much MORE would it have made without the water failure? Yall got it goin on bud, that's just all there is to it.

 

[IQ52]

But Jim, what I've always wondered was, how much MORE would it have made without the water failure? Yall got it goin on bud, that's just all there is to it.

The engine they ran without the water was our 500" engine with 906 heads. It made 730 HP @ 56% leak down, with the 15 warped and bent valves and collapsed rings.

The 451 with Edelbrock RPM heads made 723 HP during the contest, to best the other 451s by 135 HP, and later made 787 HP.

 

[RustyRatRod]

DAMMIT man. That's just all I got. lol