FM15 with ported heads
Thread Starter
TECH Regular
Joined: Apr 2003
Posts: 446
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From: Lexington, KY
FM15 with ported heads I got my car dynotuned today. Last time I dynoed it put down 399 RWHP and 380 RWTQ on the Superflow dyno. That was with the FM15 (Ron Jeremey) cam.
Since then I had my stock heads ported and polished by Force Fed High Performance and I installed an ASP pulley. With these modifications my car put down:
426rwhp and 394rwtq on the Superflow dyno
Dynojet correction factor was 2.6% which would make the numbers 437rwhp and 404rwtq on a dynojet.
This is with stock size valves. The only additional modification was the change from TSP true duals to a custom 3" mandrel bent system that goes under the axle. This would probably hurt more than help the hp in comparison though.
I am extremely happy with these new numbers and I'm amazed at how much hp can be picked up simply by porting the stock heads. Two thumbs way up for FFHP, they did an awesome job on my heads.
I'll post the dyno graph and flow sheet for the heads once I get them scanned.
Since then I had my stock heads ported and polished by Force Fed High Performance and I installed an ASP pulley. With these modifications my car put down:
426rwhp and 394rwtq on the Superflow dyno
Dynojet correction factor was 2.6% which would make the numbers 437rwhp and 404rwtq on a dynojet.
This is with stock size valves. The only additional modification was the change from TSP true duals to a custom 3" mandrel bent system that goes under the axle. This would probably hurt more than help the hp in comparison though.
I am extremely happy with these new numbers and I'm amazed at how much hp can be picked up simply by porting the stock heads. Two thumbs way up for FFHP, they did an awesome job on my heads.
I'll post the dyno graph and flow sheet for the heads once I get them scanned.
Last edited by LS1Maniac; Apr 13, 2005 at 08:10 PM.
Thread Starter
TECH Regular
Joined: Apr 2003
Posts: 446
Likes: 0
From: Lexington, KY
Originally Posted by TJ
less than 20hp and only 5pd ft with a ported head?
id hope you picked up power under the curve.
id hope you picked up power under the curve.
Originally Posted by LS1Maniac
It was a gain of 27 rwhp and 14 rwtq over the stock heads. For just porting the stock heads and using stock valves I'd say it was well worth the investment.
your hp #'s have been changed.
from the 1st set of #'s you posted, there was a 18hbp and 5pd ft difference.
could have been you posted the wrong #'s to begin with.
now that you edited the post, i look like i cant do math.
Thread Starter
TECH Regular
Joined: Apr 2003
Posts: 446
Likes: 0
From: Lexington, KY
Originally Posted by TJ
your inital post has been edited.
your hp #'s have been changed.
from the 1st set of #'s you posted, there was a 18hbp and 5pd ft difference.
could have been you posted the wrong #'s to begin with.
now that you edited the post, i look like i cant do math.
your hp #'s have been changed.
from the 1st set of #'s you posted, there was a 18hbp and 5pd ft difference.
could have been you posted the wrong #'s to begin with.
now that you edited the post, i look like i cant do math.
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Verdad Gallardo Thread Starter
TECH Regular
Joined: Apr 2003
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From: Lexington, KY
Originally Posted by Bo White
Are they stock size valves or the actual production valves? Good #s either way. 
Gomer, it peaks right at 6500 but it doesn't fall on it's face after that with the ported heads like it did with the stock heads. It actually only looses 5-10hp from 6500 to 6900. The stock heads just don't flow enough to carry on the power band after 6400. I hope to get the graph soon, I'm just waiting on the shop to e-mail me the pic of the graph
.
Originally Posted by LS1Maniac
They are stock size Manley Stainless Steel Valves. They're a lot stronger than the production valves.
Gomer, it peaks right at 6500 but it doesn't fall on it's face after that with the ported heads like it did with the stock heads. It actually only looses 5-10hp from 6500 to 6900. The stock heads just don't flow enough to carry on the power band after 6400. I hope to get the graph soon, I'm just waiting on the shop to e-mail me the pic of the graph.
Gomer, it peaks right at 6500 but it doesn't fall on it's face after that with the ported heads like it did with the stock heads. It actually only looses 5-10hp from 6500 to 6900. The stock heads just don't flow enough to carry on the power band after 6400. I hope to get the graph soon, I'm just waiting on the shop to e-mail me the pic of the graph
.
