Procharger experts needed
#11
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The Edelbrocks are a good deal when you consider they come with the inconel exhausts and good intakes. Valves for your existing heads are going to cost 500.00 alone. Then you have to think about seat work and valve guides. Aluminum transfers heat better which helps to control detonation also.
#12
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Originally Posted by baronbob
I would like to keep my heads but I will look into the heads you suggested. If I keep my heads I guess what you are saying is that new valves, perhaps larger will be wasted compaired to the cost/benefit of the larger port heads and you also state my plennum will still work.
I won't go down that road again...
![Roll Eyes (Sarcastic)](/forums/images/smilies/rolleyes.gif)
Yes, your intake will bolt on aftermarket large oval heads.
I spoke to Tyler Crocket at length about the L-29 engines a few weeks back as I'm rebuilding one this winter. So I have another suggestion for you. I bought a GenVI 454/502 mag cam from him to replace the cam as well.
It has about the same lift but more duration and will work well with the MPI. I think the $100 is worth and extra 30HP. Probably more than 30HP with the supercharger.
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Patrick
#13
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I have a set of 2000 502 mag mpi heads with about 150 hours on them. The heads are complete, the motor ran fine so there is no damage to them. I also have the rocker arms, keepers, and valve covers, cam and lifters that I could package with the heads. Pm me if you are interested.
I decided to go with a set of Canfield heads, a custom ground cam and some roller rockers. Like I said there was nothing wrong with the parts I took off.
I decided to go with a set of Canfield heads, a custom ground cam and some roller rockers. Like I said there was nothing wrong with the parts I took off.
#14
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Originally Posted by BADKACHINA
I have a set of 2000 502 mag mpi heads with about 150 hours on them. The heads are complete, the motor ran fine so there is no damage to them.
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#15
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Originally Posted by Pat McPherson
I don't believe that the GM large oval intake on a 7.4MPI will work on rectangular port heads.
You're right, he'd need to get a new intake. The heads would be that much better than stock though.
#16
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Just a question here...Is this a 1997 or so 330 hp MPI or a 98 or later 310 MPI.
Only the 310 had the Vortech head where as the 1997 330hp version had the peanut ports with a Mag rectangular intake bolted on it.
Dave
Only the 310 had the Vortech head where as the 1997 330hp version had the peanut ports with a Mag rectangular intake bolted on it.
Dave
#18
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Originally Posted by PatriYacht
That's a wierd combination.
![EEK!](/forums/images/smilies/eek.gif)
Both the 454MAG MPI and the 7.4L had the same MPI intake (805233A6). Nice mismatch; rectangular ports feeding into peanut ports.
The 7.4LX was the new 20hp less Vortech motor in 1998.
Very weird indeed...
Dave
Last edited by Nordicflame; 12-14-2005 at 04:17 PM.
#19
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Originally Posted by Nordicflame
Agreed ![EEK!](/forums/images/smilies/eek.gif)
Both the 454MAG MPI and the 7.4L had the same MPI intake (805233A6). Nice mismatch; rectangular ports feeding into peanut ports.
The 7.4LX was the new 20hp less Vortech motor in 1998.
Very weird indeed...
Dave
![EEK!](/forums/images/smilies/eek.gif)
Both the 454MAG MPI and the 7.4L had the same MPI intake (805233A6). Nice mismatch; rectangular ports feeding into peanut ports.
The 7.4LX was the new 20hp less Vortech motor in 1998.
Very weird indeed...
Dave
To bad, if he had the wacky combo, a set of used rec port heads would be a great way to go...
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#20
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Sorry I have not responded sooner. My wife and I went off to San Francisco for a get away. The motor is a 1998 7.4MPI with L-29 heads. The edelbrock large oval heads sound good. How much and where? Will this up-grade effect my piston selection. Should I aim for 8.5/1, 8.9/1???