Having not been satisfied with my first peanut port dyno test, 475 541 HP 582 TQ, a customer was nice enough to give me a second chance at this combination. 469 CID 9.6 comp, Isky 280 mega cam on a 112, ported 236 peanut port heads, RPM air gap intake, 850 holley, 1 inch 4 hole spacer, GM LS6 stamped rockers, moroso pan 5.5 quarts of 30w oil.
236 peanut port dyno test, second time around
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and to think I recommended 'worked' PP heads to a guy building a 434 BBC just yesterday....suggested good through 5500 with 434 cubes...yet power still rising at the end of the chart with 475 cubes. Hmmmm, might take a 434 to 6000 rpm. Hmmmm 396/402 to maybe 6400-6500 rpm...hmmmm
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what type of spacer? just a phenolic one? or is it tapered?
aaron
aaron
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That's a torque curve that a marble wouldn't roll off of and with big numbers. Nice job.
I'm not asking for details, but how extensive was the port work?
I'm not asking for details, but how extensive was the port work?
Strait edelbrock 4 hole
It was about the same work that I do to the 781 or 049s, 280 by .400, about 290 @ valve lift
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Mark, I think I hate you, J/K. Those are the numbers I'm hoping to get from my 509 with more head/cam. Have you set a price on this combo yet? I noticed you still offer the 475 with solid or hyd cam, maybe sell the hyd engine with PP since there isn't much power difference?
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That's a stump puller!!! It looks like the H/P was still climing at 5600 is there a reason for stoping there?? 280 @ .400 That is pretty good flow for those little dudes.
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Wow. I wonder what the torque numbers were from 2000-4000 rpm? Close to 600 I would suspect.
Mark would these heads (after your work) be suitable for a street 496 or is that just asking too much? The reason I ask is the power band looks like it would handle a low reving stroker. Say, no more than 6200 rom?
Mark would these heads (after your work) be suitable for a street 496 or is that just asking too much? The reason I ask is the power band looks like it would handle a low reving stroker. Say, no more than 6200 rom?
That is what I am wondering
Very nice! I had a set of peanut port heads on a 461 that was in my 71 corvette, had about 8.75:1 and a comp XE cam 480/485. I thought they were great on the street, kept the 3.08 gears and stock stall in the car and could still fry the tires off from a rolling start if I wanted to. I think these heads have an undeserved bad reputation. Thanks for sharing.:thumbsup:
X2
Great job Mark! :thumbsup: I am sure the customer will be very happy with the performance
Considering you did about the same amount of work on these heads as the 781-049's, what do you think the power difference would be if you did your own dyno shootout. Would your 781/049's blow the peanuts away or would the peanuts own the bottom end numbers and get stomped on the top end?
As for the 280 Isky, I love that cam. I run that same grind in my chevell's 427 with pocket ported 781's and it flat out rips (at least did before I hurt it. Several years of abuse, and my stupidity caused a little damage)
Great job though. Aren't those flow numbers in line with unmodified GM rectangle ports?
As for the 280 Isky, I love that cam. I run that same grind in my chevell's 427 with pocket ported 781's and it flat out rips (at least did before I hurt it. Several years of abuse, and my stupidity caused a little damage)
Great job though. Aren't those flow numbers in line with unmodified GM rectangle ports?
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I have been reading this forum for a long time now, but this is my first post. I'm building a 427 .060 with PP heads #360, not 236. Is there any difference between this 2 heads? Mark, did you ever got around to flow test yr PP 236 with a stock GM Aluminum big port intake? Great info about the PP heads, Mark! Thanks.
I think the low lifts are better than a 840 or 990 head, but I think a 990 peaks about at 310, and a 840 peaks about 280 on my bench, I think 570 hp and 600 tq would have happened if it was a 475 instead of a 469, and had roller rockers instead of LS6 rockers, it sure was responsive, thanks Mark
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