LS2 427n/a #'s not what I thought
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LS2 427n/a #'s not what I thought
here is what I have. resleved ls2 ported/polished ls1 heads 244/244 612/612 mti s1 cam 90/90fast 1 3/4 headers 3" y pipe gmmg exhaust. numbers came back at 455/460. was thinking and wanting over 500. all thru a m6 car peaked quick at 5800-5900. Guy that did the tuning and dyno said it makes it power quick.
with that said I know there are better heads and maybe even a diff cam that would get me there. I just dont know where to start. any info would be apperciated
with that said I know there are better heads and maybe even a diff cam that would get me there. I just dont know where to start. any info would be apperciated
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Do you have any shots of the graph or any other information from your session? There is a lot to guess at here.. At first thought, yeah, I would guess the heads are holding you back. But we need more information to give you a better idea where to start. Any more information on those heads would be helpful.
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ugh dont say that. Something like that wouldnt have shown up some how during my session.
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Honestly, you said that it was done making it's power quickly.. that's where I'm curious.. If those heads have been used for a couple of years, and are the original springs from MTI, maybe the springs are worn out, causing you to float the valves? If you are going to run a compression check, why not do a check up on your valve springs to see where they're at? That shortblock sounds like a nice foundation, so if it checks out alright... I would recommend pulling the heads, and shipping them to a Vendor like TEA or AI.
Advanced Induction offers a rebuild service on cylinder heads for under 500 bucks that will have them working as new. As a bonus, if there is anything wrong with them, they can make the necessary repairs/replacements, restoring any lost performance.
I'd say its money well spent! Moreover, if you decide that you want to run a different cylinder head, having these gone through and brought back to prime condition will make it much easier to sell them, giving the next buyer a solid head to work with... It would make it a much easier sale.
The more info you can get on your build, the easier it is to trouble shoot, and diagnose any problems that might pop up. This is where it pays to be an informed buyer, you know? Good luck, keep us updated on any progress!
Advanced Induction offers a rebuild service on cylinder heads for under 500 bucks that will have them working as new. As a bonus, if there is anything wrong with them, they can make the necessary repairs/replacements, restoring any lost performance.
I'd say its money well spent! Moreover, if you decide that you want to run a different cylinder head, having these gone through and brought back to prime condition will make it much easier to sell them, giving the next buyer a solid head to work with... It would make it a much easier sale.
The more info you can get on your build, the easier it is to trouble shoot, and diagnose any problems that might pop up. This is where it pays to be an informed buyer, you know? Good luck, keep us updated on any progress!
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That shortblock sounds REALLY nice, actually. And the Cylinder Head is older, but may still be a performer! We don't know yet. He has nice parts, he just needs to invest some time and money into the little details. Those heads may need a few hours of work, but when finished, he may find 50 horsepower!
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FAST 90+ 1 3/4 long tubes+ a 3" ypipe are all less them optimal for a 427. If it were at least a ported FAST 90+ 1 7/8 headers+ 3" true duals id almost guarantee he'd reach his goal.
My guess on the reason is peaked early is the intake and exhaust couldnt keep up at higher rpms. ANd the above shows restrictions in the intake and exhaust. Clear those up and youll have a stout combo.
Also, speed density or maf tune? If a maf what size is it?
My guess on the reason is peaked early is the intake and exhaust couldnt keep up at higher rpms. ANd the above shows restrictions in the intake and exhaust. Clear those up and youll have a stout combo.
Also, speed density or maf tune? If a maf what size is it?
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I dont think he is going to pick up 50 RWHP from a change in primaries and a port job on his FAST manifold. NO, those headers aren't enough for a 427, and he's leaving some on the table. And YES, porting that FAST manifold, or a switch to the 102, would help his combo make more power, but ONLY if the motor will spin that high... We haven't seen any information from his trip to the dyno. NO graphs, no idea on his tune, no real SPECIFIC details on his combo. So the best we can do at this point, is guess.
I agree he is leaving a considerable amount of power on the table with his 1 3/4 headers and untouched FAST 90, but I don't agree it's worth 50 RWHP....
I agree he is leaving a considerable amount of power on the table with his 1 3/4 headers and untouched FAST 90, but I don't agree it's worth 50 RWHP....
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FAST 90+ 1 3/4 long tubes+ a 3" ypipe are all less them optimal for a 427. If it were at least a ported FAST 90+ 1 7/8 headers+ 3" true duals id almost guarantee he'd reach his goal.
My guess on the reason is peaked early is the intake and exhaust couldnt keep up at higher rpms. ANd the above shows restrictions in the intake and exhaust. Clear those up and youll have a stout combo.
Also, speed density or maf tune? If a maf what size is it?
My guess on the reason is peaked early is the intake and exhaust couldnt keep up at higher rpms. ANd the above shows restrictions in the intake and exhaust. Clear those up and youll have a stout combo.
Also, speed density or maf tune? If a maf what size is it?