L31 5.7L Vortec - CSFI conversion to MPFI

Hello.

I got one truck with this engine, they installed a procharger and brought it to me for a tune. As you know the spider injectors have not enough flow for forced induction so I want to swap to regular injectors with rails.
I have seen some threads where several people have used a marine intake with rails that is supposed to be almost plug and play with minor modifications. However the threads are very old and the pictures and links don't work anymore so it's not clear exactly which intake and rails to use.

Does somebody here have the part numbers the parts I need to do this conversion? I only need part numbers for the things I need (intake, rails, gaskets etc), I can do all the mods, wiring and tuning needed, I just want to be sure I have a complete list of everything needed to be able to provide an accurate quotation to the owner.
Hope somebody can help.

Thanks in advance.

Holley might be an option: https://www.holley.com/products/inta...SABEgJ3WPD_BwE

dave w

In-tech had a couple of those intakes for sale...

http://www.gearhead-efi.com/Fuel-Inj...25hp-manifolds

Thank you very much guys.

FYI, it's not cheap. Decent used intakes were bringing big money, last I checked new ones were in the $1500-1600 range, and use a 4 bolt throttle body. I did mine a few months ago, but that was because I was given a new take off a friend of mine had for free. The thread over at ppe has about all the info you can find on the swap.

http://www.pacificp.com/forum/viewto...er=asc&start=0

The external injectors are the key so you don't have to rely on the "spider". I'll help what I can :)

Quote:

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Originally Posted by In-Tech

The external injectors are the key so you don't have to rely on the "spider". I'll help what I can :)

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That they are! I am really enjoying the dual plane setup. I cleaned up the ports in the dual plane and opened the runners up to match the port opening of my 210cc aluminum heads. Swapped to a 1200 cfm 4bbl dry throttle body and a 4" air intake setup with a 100mm MAF housing. My 11:1 383 runs so well with that dual plane. Engine modeling software is showing about 540 ft/lbs of torque at 4,000 rpm and 530 hp @ 5,700. With a 5.13 rear gear and a 2,800 rpm high STR converter in the 4L85E its fun to drive despite being wrapped up in a 3+ ton van.

Ignore the carb sitting on top. Only used it for spacing to get the overall height ballparked for fitment. I ended up with a 1" open center nitrous plate as a spacer between the throttle body and manifold. Have yet to hook it up but I bet that 383 is a monster on a 100 shot.

HaHa, yepper, 100hp shot, yuck... start out at a 175hp shot :D

I can't find my drawings and strobe pics from the early 1990's. A 3 bar plate works so much better to atomize the fuel. Think top bar with normal degree exit of nitrous in a V and twin fuel bars exiting fuel so nitrous blows thru the fuel at a 90 and stratisfies in an upward pattern. Everyone to this day still puddles fuel in the center of the manifold.