I recently purchased a 2000 C3500 pickup with the 350 L31 engine. I am interested in replacing the weird intake manifold and injectors. I have searched here and am surprised to find no mention of the GMPP EFI intake manifold (Part Number 12498032) for SBC Vortec engines. I find old information about the “marine” intake but nothing about an apparently superior alternative. Why is this?

 

Hey Gary,

Did you do a search for "Ramjet"? I have the Ramjet on my truck. It is NOT a straight forward install on our trucks. I am glad I used it, but it was a lot of work to get it installed. You can check on PacificP.com also.

Jeff

 

you would need a different computer to run with that intake with seperate injectors

 

Not sure about that.

 

now that i think about that i know the 454s have 8 injectors but the 350s are they still like the 97-98s? if they are like the 97-98s it will need somethin different to run the 8 injectors versus the one main injector on the old ones

 

if you are looking into that intake and performance I would look into the 411 PCM swap it is pretty easy and would make you tuning options better.

 

Thanks for the help guys. I’m finding more information now. I don’t think I'll need to replace my 16263494 PCM. I already have HPTuners software that can read the PCM. I just need a license upgrade in order to write. Converting to newer type injectors shouldn’t present any major electrical difficulties. Technically, the L31 already has multi-port, sequential fuel injection. I just don’t like the unusual poppet-type injectors with their plumbing inside the manifold. I haven’t yet decided to change anything. I'm just learning and exploring my options.

 

it is not necessary to replace the pcm for the truck to run but it will not spin past 5800 rpm's. so depending on your cam selection that could present a problem.

 

Good point - thanks.

-Gary