Thread: L67 mild mods

3in dp or nothing.

The stock catback has no restrictions. It can flow up to 350+ WHP.

Your choice on mufflers.

Add a short 22.5º elbow and slap the filter on it and stick the IAT in the elbow.

your stock exhaust after the downpipe/headers will flow perfectly fine. mufflers dont restrict anything at that point.
why would you NOT get headers?
its going to flow SO MUCH BETTER and you can actually run the 3.4 pulley on more timing. dont chince out on builds.
you need an O2 sensor.
you can mount your filter right on the TB and tuck in the IAT sensor, or you can build your own little intake system.
the PCM you can either ziptie to something nearby in the bay, or you can let it flop. its meant to take abuse and water damage.

Why in the hell would you run the car without O2's?

Can someone please lock this thread, I am convinced that the OP is just trolling everybody. There is no way after us giving him all this info should he still be asking all these damn questions, and he keeps repeating himself in a lot of his posts.....


/end thread

Without an intercooler I would put the filter as far away from the TB as possible. You can just put the IAT inside a coupler with no problem. I just let my PCM sit underneath the filter right behind the headlight. There are PCM trays you can buy or make but Ive never used them. Make sure you get a modular pulley system and start with IMO a 3.5 and scan. As far as doing a cam, yes you take it out thru the front cover. But you have to pull the lifters out.

EDIT: Technically we run our cars without the O2 in open loop mode. But unless youre tuning off a wideband you need your upstream 02. Also thats how you tune NIC cams. But I assumed he meant getting rid of the rear 02.

Either filter will work.

Originally Posted by jsnyder49090

We have a 5000.00 Snap On Solus at work i will scan it for sure. I will build my own downpipe it will be 2.5 all the way out with a free flowing 2.5 muffler as the only restriction.I dont want it real loud not sure what kind of muffler to run maybe a borla. I been listening better guys i am thinking about the headers are the SSCA as good as the SD? Do they both have issues that need addressed? How much is shipping for the SCCA didnt say on their site? The SD's went for about 215 shipped on ebay last auction.I like what t24moore said use the pulley,intake,stat,plugs,tune and scan only.The thing is i am upgrading the exhaust full 2.5 no cat, least bend as possible, no 02 so i can tuck it in close.I am debating the headers PER Grand Prix Forums Members! Couple questions when making your own CAI should A Mount the filter right on the TB?B Use a short piece of pvc or silicone coupler and mount the IAT sensor in that? Or should i make a homemade intake and put it near the old filter box or fender? Also i removed the stock airbox what should i do about the PCM ? I would like to add a cam can this be done like a LS engine do the lifters pop up ? Am i able to cam it with just removing the front cover?

What a mess.

And of course you like that, ya cheap &$#@

Originally Posted by rynoman03

Put a 2.8 on it and call it a day already!

Knock Knock City *****.

Originally Posted by thomas mcnulty

Headers are very much heat creators. Worth it though

considering that even doing cai on a grand prix barely provides solid hp numbers gain vs going open cone, the heat created is insignificant compared to opening up the most restricted part of the exhastust, be it ****ty manifolds and u-bend. these fking cars knock stock. even n/a.

jsnyder is just going to shell it.

Then he'll be back in a month complaning about having to pull his motor because it's broke.

But that's just the fun of trolling, right?


Please visit www.trollinggpfisfunforeveryone.comz

Originally Posted by Nixon

And of course you like that, ya cheap &$#@

I could save him the trouble and swap motors w/him. Lol.

LOL again Nixon, myself as well as others ran this way for years with ZERO KR, and I been to the track many times with that setup running mid 13s and drove home with no problem. Seems like a lot of you have only been messing with these things for a year or two but think you know it all. Go over to 3800 Pro or even Clubgp. It seems like this is the only place thats scared of running a 3.5-3.4. Not trying to start **** but it seems like a lot of you all just read and take it at face value. As long as he scans and isnt getting any KR then he should be fine, if not he can always pulley up. It would be different if pulleys were expensive but they are cheap as hell with an MPS. One thing no one ever mentions anymore is letting fuel trims learn before you romp on it. Our PCMs even in stockish form are a lot smarter than people think. I think thats the biggest difference nowadays on why maybe many of you all need custom tunes and valve train mods for pulleys people used to run without issue on a damn near stock car for ages with no problems.

Thats what the aftermarket PCM is for. That is not a band aid.