Aftermarket Upper Intake??

[dan291000]

Is there anyone who makes a performance upper intake to replace this plastic crap?!?! I have searched everywhere and cannot find one...

 

[Rebelution]

If I'm not mistaken, the only other intakes that will bolt up to the 5.7 vortec are the mercruiser marine intake and the ramjet intake. The marine intake needs injectors and a few other things to make it work. The ramjet requires more work and costs a good bit more. From what I understand, neither of these swaps are worth it unless you plan on adding a supercharger.

 

[bowtiefreak]

are they emmisions legal one modified?

 

[992dr]

dan291000,
They dont make just the upper manifold, its a complete manifold. Dont quote me on this but, the reason for the two peice manifold is for access to the rediculous spider mess inside the manifold.

Here's some reading for you, all the info you need for the marine swap.
http://www.pacificp.com/forum/viewtopic.php?t=317

Rebelution,
The LT1 manifold is also another manifold that works, with modifications of course. There is also custom, which is about $1500 and looks bad ass. The marine manifold comes with injectors, ussually they are take-off models. The biggest benefit of this conversion is the ability to use larger injectors. Of course boost always comes soon after, hah. But, this mod is the best for anyone who is looking to make any serious HP, boosted or NA.

Rebelution,
Yes it is emissions legal. Check that link out, its very informative.

 

[steamroller]

neither of these swaps are worth it unless you plan on adding a supercharger.

On a mostly stock application it's not so much the fueling that is the problem it's all the restriction and turbulence that the spider and fuel meter body cause. Think about it this way, what if you dropped that big mess inside of a regular EFI intake? It would definitely hurt power. No one has done any back to back testing that I know of, so how much has yet to be determined.

There's a custom setup for sale on the PPE forums right now, wished I had the cash to throw at it but I've got too many irons in the fire. I can't believe someone hasn't scooped it up yet. If only it were around when I did the 'injector upgrade' lol

http://www.pacificp.com/forum/viewtopic.php?t=9854

 

[Danny_Z56]

Would it be a PITA to swap the LT1 intake onto our L31? This is something i'd really like to do.Getting the LT1 intake would be easy for me.

 

[steamroller]

You would have to machine a hole for the distributor, the intake bolt pattern would have to be adressed and I believe something would have to be done about the coolant ports, not 100% on that though

 

[Danny_Z56]

^ sounds to me its not really worth the trouble,esp if this mod only gained 'maybe' 10hp...(if that...)

I would say that maybe swapping an enitre LT1 motor would be easer but i dought it.Not only that but the LT1 only has 5hp more than our L31's.(B-body LT1 260hp,L31 255hp) Im guessing our clutch fan robs 5hp... As far as torque rating goes,B-body LT1-330tq,L31-330tq....

 

[steamroller]

Yeah the LT1 intake might not be worth it unless you had it laying around and the necessary tools to pull it off, especially if you're completely stock and don't ever plan on doing any mods. The Vortec heads have been shown to be a little better than the LT1's heads too though so that makes you wonder how much of a difference it would make.

The Ram Jet engine is a good comparison IMO. Same heads, same compression, a slightly bigger, but still tiny cam (L31-191/196 RamJet -196/206) 22 lb. LT1 injectors and the different intake gets you to ~350 hp, 400tq with conservative GM tuning. There's no way just that cam is making that much difference