I am just looking to see if anyone knows where I can get a used Ls6 intake with the egr provisions. So if you have one or you know someone that does, I am looking to buy one. The next thing is if I cant find a used one slp has a brand new ls6 intake for about 550. Am I better to get the slp intake or the fast 90 for about 200 dollars more. And then the last thing, if the fast 90 is the better way to go will I be able to use my ported and polished throttle body or will I need to get a 90mm throttle body to go with it. But I would like to just find a used ls6 intake most of all Thank you all so much.

 

You will see more horsepower from the FAST intake than you will from the LS6. The difference will be small, but the FAST is better equipped to grow with you if, for instance, you some day decide to bolt on a supercharger or something.

There is a smaller (75mm I think) throttle body that works with the FAST, but I don't think you can use your stock one.

 

Can't help you there. But keep an eye on ebay and the for sale section at ls1tech. If you're patient you'll find a used one.

Well that depends. If you are sticking to bolt ons then the fast 90 is a waste of money. Heads and cam cars however have seen 10-20 rwhp gains over ls6 intakes. If you plan on internal engine mods then get the fast 90/90 setup. Otherwise I would just get a LS6 intake and use the money saved towards another bolt on or suspension upgrade.

If you get a fast 90 then you need a 90MM throttlebody so no your ported throttlebody will not work. You can get a fast LSX intake with a 78MM opening. That would work with your current TB but it's going to gain little (if anything) over a LS6 intake. Not worth the extra money IMO.

So I say go with the LS6 intake unless you are planning on big mods in the not too distant future and don't mind spending $1200 on a high flow setup.

Good luck.

 

I don't know of many LS6 intake manifolds that have the EGR provisioning built into them (maybe California-spec cars?)... I've never seen one before.

You can use the LS6 intake with a ported TB up to the cam-only or lightly ported heads + cam level along with a ported stock TB up to around 450rwhp NA. The FAST 90/90 is worth roughly 15-20rwhp over the LS6 at that point.

I'd recommend posting a thread in the Parts Wanted section of this site and searching this site and other LS1 friendly sites for parts.

This is the incorrect forum to post a question like this into.

Mike