1996-PoloZ28

Hey everybody new to the site, this is my first post. I have recently picked up a 96 z28 m6 and am starting to put together my plan for performance improvements. The car currently has a borla cat back, k&n cai, trick flow elbow, Hurst short throw, and zr1 style ss wheels and tires. I have done a full tune up, next I want to do pacesetter long tubes, y pipe, 1.6 RR, lt4 springs, and a mail order tune. What y pipe is best to use with the long tubes? Will it constantly throw a check engine light without the cats? What tune should I use, pcm4less madz28? Will an aftermarket throttle body help at all? Thanks for any help and suggestions.

bufmatmuslepants

iTrader: (3)

Pacesetters come with a y pipe, any of those tuners is fine, trifecta, Ed wright, etc also. No on the throttle body, stock is fine to over 400rwhp. Your tune will delete rear 02 sensors so no codes.

pillarpod

Welcome to the LT1 world

Pace setters are cheap, but I had to modify their Y pipe to make them fit. Could always have an exhaust shop make you one. It will throw codes if you don't get the cats delete. I went with Ion (madz28) for a mail order.

bufmatmuslepants

iTrader: (3)

My pacesetters fit great, bolted right up to everything clean no mods.

1996-PoloZ28

Thanks for the help guys. Ya this is my first lt1 so I'm still learning a lot.

How bad are the pacesetters to install? Luckily I have a lift in my garage so it will be easy to get to from the bottom if I need to. I drive the car a lot on the street and want to keep it reliable as possible, is there enough benefit to to make it worth removing the AIR/emmisions system? Or should I use headers that have provisions for the lines?

hokeplaya05

iTrader: (3)

get rid of the air/egr stuff, then you can have them tuned out. having a lift will make a ton easier to instal them, i installed mine while i had my motor/k-member out of the car, cant get much easier than that. only way an aftermarket TB will help is if you are 400hp+ and you have your intake ported to match the TB. good luck

bufmatmuslepants

iTrader: (3)

I wish I had just deleted the EGR and air and emissions stuff when I did the headers, theres really no point to NOT get off road ones because you wont pass the sniffer anyways with long tubes in most states as the cats are put too far back to heat up enough to be effective. Just get the off road ones, delete all the emissions crap, it cleans up your engine bay a ton and makes it easier to work on, and anything you can do to make it easier to work on these cars, is a huge bonus.

Austin_Ws6

I went with madz28 for tuning and was more then happy. Only had a couple bolt ons and it really woke the car up. Headers can be a pain in the *** lol. Have you looked into gears? It will wake the car up nicely also.

1996-PoloZ28

I've thought about gears, maybe some 3.73's. I see a lot of people say to go with 4.10's with the m6 but I would like to keep my mileage close to what it is now.

BALLSS

OP

while the LT4 springs are cheap.....given the effort it takes to replace I would go with a better spring as the LT4 springs are barely, at best, a upgrade.

might want to consider Comp 918's or PAC springs of the same #. Will need new retainers and can use your 7 degree locks. also good reports on Alex springs but I have not run them.

replace the valve stem seals while doing a spring swap. FelPro

4:10 + M6 is a good combo. With a 27" tire I tach 19++ rpm at 80 mph in 6th. There are online gear/rpm/mph calculators to figure out RPM's for a given gear/tranny you can check out. Note 4:10 can be known to be weak if launching high rpm clutch dumps with a tire on the 7.5 rear end.

bufmatmuslepants

iTrader: (3)

FWIW my buddy just bought a 95 formula M6 this weekend stock with just an intake and flow master catback, before we went to test drive it we went for a ride in mine, with mods in sig. At 40mph in 2nd on 295 tires, if I mash it it spins (50 degree air and no LCA relos yet could have helped). Then we drove the stock manifolds stock tune formula with only 82k miles, which is in great shape, and the power difference is incredible. We're going to the track in the next couple weeks, and the ltx shootout on the 16th, but I don't expect the formula to run better than 13.9 at 100. Just headers and a tune more, I was at 12.5 at 110 still on stock tear end, suspension, waterpump and valvetrain. Headers and a tune wake these cars up SO MUCH. Just the power from 5-6000 increase is incredible, I shift mine at 6200, the stock car runs out of breath at 5300 and begs to be shifted.