exhaust and intake questions
 

Ok well I finally picked up the z28 last week (pics this weekend, I promise). I pretty much knew most what there was to know about 3.8s and performance mods, but know I have to learn a whole new world.

So I thought I would just get some quick questions out of the way. The z28 drives like a cadillac compared to firebird, id like to keep it that way. As far as performance would just like to stay bolt on, car has 2.73s and nitto DRs so hopefully the 10bolt will last a while.

So I think first Id like to get some LTs. I was just curious, when people added LTs, did it effect drivability that much? Interior noisier? More rattles and vibrations? I was looking at some used QTPs with 3" y pipe. Hows the fitment and ground clearance?

LS6 intake and P/P tb. Seems like on tech they go for around 300 usually, but some come with fuel rails and injectors and i think egr provisions? or some type of emissions provisions? So what should I be looking for? I mean I can use my fuel injectors and other parts correct? I just need the intake? As far as P/P the TB, anyone local good? is it that hard to do myself?

Sorry for maybe some obvious dumb questions, the lsx series motors are just all knew to me and so much different then the 3.8 haha. Any tips or insight on what I should get, or what route I should go will be awesome! just let me know, im all ears. Thanks!

As for driveability with LTs there arent really any major issues it will be louder interior wise and u will get some vibrations and rattling...its only natural in these cars lol..As for QTPs not sure how easy they fit dont kno anyone thats used em personally..brand all depends on what ur willing to spend. U get what u pay for imo.

As for the LS6 intake u can get either with EGR or non EGR...id go for non EGR and get rid of all that crap, or u can get the EGR one which may be easier to find and just buy block off plates to delete it. U dont need to change ur fuel rails etc and most used intakes are around 300 so thats not a bad price. Also keep an eye on what ur buying when its used stuff most people dont kno the difference between an LS1 and LS6 intake they have different part numbers so make sure u look at pics before u buy anything. As for porting the TB Don does em for a decent price...U can do it urself tho but its kind of a pita.

Dont worry weve all been in ur shoes at one point..ull catch on they arent a hard motor to learn about or on

I wouldn't start with longtubes personally. If you don't change out the cat back first you aren't going to see any gain. If it were me I'd do a nice cat back (IMO Maganaflow) the LM1 is not a very good piece and makes more noise then power, a real LS6 intake (not the SLP EGR one) Delete the AIR and EGR systems and P/P the throttle body and see how you like it. The SLP lid is one of the best on the market so you should be good there. If you do decide to do headers keep in mind it gets exponentially louder when you delete the CATS, especially if you keep the LM1. The QTP headers are very nice and fit well but their Y-pipe is absolute crap and leaves around 2 inches of ground clearance and bangs all over the floor so I'd stay away from theme. Best headers I had were Kooks, big power gains and professional fitment.

definitely a cat back first and then go from there.

my brother is on the same ride and we'll be putting on his catback tonight. he's on a budget so we ordered up a Hooker c/b. (I have one and love it)
definitely get the simple stuff out of the way 1st. If it doesn't have a lid, get one. any vendor sells the SLP one for $100.

headers best bang for $ ARH/QTP//Kooks. all stainless. again based on budget your thoughts and options change. most of us that run the coated Pace setters love them, but know the risks of rust in our part of the world is high and you'll prob. replace them in 6yrs or so. (personally will likely splurge on stainless when the time comes)

and I'd look into new rear end gears

I really like the LM 1, I love the sounds,and its not as obnoxious as I thought it was going to be, only up top it is.

Ok so should I keep an eye for ls6 intake without EGR and just go ahead and delete that stuff.

Do those kooks headers provide good ground clearance? I wanted to keep cats, but from what Ive read its really not worth it. It costs more, more things to replace, and technically LTs are illegal anyway so even with cats im technically still illegal. So with a catless y pipe and LTs what would be a good catback that isnt really loud? I wanna still be able to pass inspection, but if I have a catback thats stupid loud I dont think my guy is gonna let me slide.

Im sure once I get the LTs and ls6 intake Im gonna need a tune right away? Not only for SES lights because of the EGR and cats, but will also run to rich?

thanks for the good info!! whats the part number for ls6 intakes? so I dont get screwed over.

I would love some 3.73s or maybe 3.42s, but that just seems like thats asking for trouble with the 10 bolt. Im actually nervous about throwing on my nitto DRs. But the BFG g forces dont hook up for crap, even with the 2.73s.

If youre gonna do full exhaust go for Magnaflow or Hooker, the LM1 will be way too loud after that. And gears really would make a world of difference, and by themselves dont make the 10 bolt any weaker, unless you get 4.11s. Its often easier and cheaper to get a used 10 bolt, just make sure you get the right one - 3 channel if no TCS, 4 channel for TCS.

Yeah LM1 gets very loud with longtubes and pretty much unbearable if you delete the CATS. all the GM LS6 intakes will be without EGR be aware that Corvette LS1 intakes had no EGR so make sure it is an LS6 (anything 01 and newer will be). And really for the mods you have now you should have a tune done. But def if you delete AIR or EGR you will need a tune and also if you do headers you also absolutely need to, so plan accordingly so you only have to do 1 tune

Ok, thanks for the info. So is slohawk still doing if you buy some kooks headers off him he'll install them? If I could just do my exhaust, ls6 intake and p/p TB all at once and get it tuned at his shop that would be awesome, and save me some coin on gas money driving up there.

hows the ground clearance with kooks? I heard that I think it was LPP the clearance wasnt great and they also would hit against the firewall or something, so youd get a bang every now and then, anything like that with kooks?

With magnaflow, will I be able to pass inspection? I know magnaflow is one of the more tamed exhaust down low, so you think itll be quiet enough to pass? Or will it louder then my current LM1 set up once I get the LTs?