Thread: LS2 intake install

Installing the ls2 intake was just as easy as the LS1/6, All the same things need to be done except the ls2 already has a map sensor port up front. But using the stock ls4 fuel rail and injectors was awesome especially for those not wanting to cut your alternator bracket, like you would the ls1/6.


Cutting the VLOM was a breeze, being the soft aluminum that it is a dremel will easily handle the reworking of the oil passage. If i could do it all over again id just drill throgh the non cut tower into the feed port and tap it. but thats another story. Next time this valley cover cover comes off itll be because im pulling the heads etc...


Its good to know the DT headers crossover pipe fit but barley. the crossover was damn near touching the coupler so i had the crossover shortened 1/8 inch and rewelded at the ball flage joint. now i have plenty of space.


here are the pics from my LS2 swap hope this can help give a visual.


the VLOM cover rough pic of what i was doing the inside.





all welded up





my modified oil cooler block off plate **note The corvette OFAC is not a bolt on item. the holes arent aligned the internal shape is smaller.


here is where the plate is located








Picture of the modified brake booster fitting and additional fitting i added to the front of the manifold






everything mounted up





Also note 05-06 GXP's can use the longer oil filter PF61 acdelco for more oil capacity.


Misc notes.


you will probably either have to peel your map harness out the loom or use an extension, The TB and factory wiring harness can be a tight squeeze with the hoses in the area, my loom pressed against thdogbone mount to the cylinder head, which carries alot of heat. I made sure to wrap with some cloth friction tape then reflectix material so my loom wouldnt burn against that hot ass aluminum





LS2 intake manifold with tb swap on LS4 - YouTube
Thanks for looking and if you have anything for me please feel free to ask.

Make me one.

I think it's great how you keep doing various setups and proving out how easy/hard etc they are.

Jealous. I think this deserves sticky in 5.3 section. Love how the 5.3 section is finally getting some great write ups for others in there

Originally Posted by Kyne

I don't know much about the LS4 but I do know the LS2 intake is arguably the worst LS intake made power wise. Because of the crappy job vibration welding them. Any reason to switch to it other than it has a 90mm TB? There is a company who makes LS6 intakes with a 90mm snout as well.

In stock form sure guest I need to add what I did to make it perform like an ls6 if not better. Runners are all port matched, inlet is 92mm post have removed inside. Gto guys claim 5-10whp just by doing that. I also went around the case and plastic welded it to itself. So no leaks.

And for bang of the buck and if you have the skills to port your own **** ls2 is a no brainer

Originally Posted by Kyne

Fair enough I will say that the ported ls2 intake has fallen out of favor in the 6.0l Gto world since about 2010 I would say. Reason is the power to cost wasn't really there. I am a Gto guy and had this bandaid before too. 5hp over non ported I would say is correct and 10 is pushing it. I just looked and the ls4 engine comes with a 78mm TB so I guess the upgrade to 90mm is a good reason.

The ls2 (ported or not) has never been considered an upgrade from the ls6 found on the 5.7 Gto though and I think that is a more telling example than the 6.0 since it seems keeping the 78mm TB and the ls6 intake than going to a 90mm and switching to the ls2 isn't worth the time and money. Seems the fast isn't an option on the FWD v8 so you are stuck with those stock options. I'm curious if the tpis manifold would be a viable option for the ls4 guys.

Ive also ported numerous ls intakes and in the past two years or so the ported ls2s are a very hard sell. On my Gto I have a full square port top end with the ls3 style intake and have been doing those conversions to a few vehicles and have some spare ls2 intakes laying around that I can't seem to sell.

This isn't any argument though because IMO you've probably fixed the ls2 shortfalls. A little with the porting but I think you really helped it out with welding up the ports correctly so there is no leakage from port to port. Any results to come from before and after that little mod?

We can do f.a.s.t intakes as well just is a little more involved. I'll post the pics and dimensions of the stock ls4 intake. The butt dyno is pleased with this upgrade still knocking out some tuning and waiting for a wideband display so I can get this iteration of tuning done via AFR error and not fuel trims. Eventually I'll be snatching stuff for cam and heads. And I'm sure my trans will blow sooner or later although she's still holding. So far though this thing I pulling a lot more air than my ported ls1/ls2 tb combo and satisfied with the diy work i did. I'll post on later tonight

Im liking where this is going and for the ls4 I believe that ls2 intake is still a great upgrade. Im also interested to see what numbers you can get from it, are you planning on getting it on a dyno after this mod or waiting till after a heads and cam swap? It would be cool to see the differences in-between but dyno time is not cheap.