Hey guys, I sold my 12 second 5.0 earlier this year, and just picked up a 97 Z28 (A4 2.73 gear)s with 49K miles for 9K, in good (but stock) shape.

I did a few of the free mods I've found poking about this site and others, and it's time to throw some money at it.

First of all, I'm a nitrous freak, ran a 175 wet shot on my stock bottom end 302 with no problems. Lots of supporting ignition and fuel mods in place though .

I'm looking at spending about 2K or less in mods, so I wanted to bounce my ideas off you and ask a few questions.

1) CAI kits, Lingenfelter, SLP, K&N, any particular advantage of one over the other? This is mod number one.

2) Gears, I've read 3.73's for the auto cars, and since it's primarily a street car and will only see spray to punish the unsuspecting, I still feel it's an appropriate ratio. How do I get the speedo recalibrated to be correct?

Do any of you guys "share" a Hypertech programmer or anything in particular geographic areas to accomplish this?


3) Nitrous, gonna use a Nitrous Works 150-175 wet kit, Jacobs Nitrous mastermind, MSD 6A and probably an inline high rpessure fuel pump. Looking at the instructions in Chilton's, I can see why nobody wants to swap the intank pumps, jeebus what a PITA!

What is the stock piston material in 97, cast, hyper or forged?

By the time I've got the above kit and stuff (plus a bottle warmer)
I'll be in the N2O around a grand I think, so with labor for gears and an install kit, shouldn't this be around 2 grand? What kind of E.T.s would I be looking at approximately on some DR's?

By the way, I flipped through the first 30 pages of this forum, learned a lot, have some good plans for when I have lots of cash (yeah right) but seems like this is a good place to start.

Thanks again,
Chris

 

For a referance for ya. Last year before I decided to pull my motor for my new 383. I was running a 12.10's in the quarter with a 95 T/A with 160,000 miles on her with a 150 hp nitrous dry kit. Would of hit high 11's if it wasnt like 95 degrees out with 90% humidity. Only mods where:
52mm tb
msd 6al box with spark retard for nitrous
1.6 roller tip comp rockers
modified air box
descreend maf
No cat
Edelbrock muffler( Yuck)
4:11 gears

 

Well, from what i have heard...there is a lot that you can do with 2 grand to an LT1 to make it go 12's. There is a heads and cam package from GM, youll have to look around for sure, that costs about 2 grand that guarantees 12s. But that doesnt include labor. For the computer...the best bet is going to www.pcmforless.com they take the stock computer and recalibrate it to whatever you have done to the car. Kick around that site...they have an order form that you can look at with all the different specs that they do. Good luck man...and welcome to the better side...

 

It cost me a little under 2 g's but I did all the labor myself including the rear end. Watch how much nitrous you intend to spray. LT1's have a poor head gasket composition and Nitrous will literally eat them up. I have some nice ones hangin on my wall of "LT1 wall of shame" That had the steel ring literally melted away by running to much nitrous.

 

congrats and welcome!!

1-when it comes to cai i say either the K&N style one or the SLP one. moroso and lingerfelter are basicly the same as k&N but i beleive are cheaper so if its money thing i say go for the lingerfelter, i think its like 149 or something and works pretty nice. if your looking for style then go for the SLP one, its more expensive and looks better, but soppevly gets less gains (HP) due to the metal material it is made of versus the plastic the others are made of (sopposdly soaks heat or something but its arguable) if thats a big deal to you get it cermaic coated or something.

2- if you switch to 3.73 im sure you will feel a BIG diffrence, i think those are one of the best gears you can get (in the respect of balance between power and drivablity)
if you are gonna spray i say stick with those, if not ive heard alot of good about the 4.10s but cant say for sure. but you cant go wrong IMO with the 3.73, i beleive with a power programer you can hook a computer up with your car and do it that way.
they have allot of services that do that, im sure a mechanic will do it for you too.
i dont think you can share the hypertech programers. once you use it on one car you must change the settings back to stock before you can use it on another, but ones you hook up to a lap top can be shared.

3-nitrous....hmmm to be honest with you i dont know much about nitruos, all i know is our stock engines cant take 175-200 shot without ****ing something up, if you want to be safe go for a 75-100 shot, you wont need to change anything, anythign more and i think you will need to modify somehting.
i think if you do all the work yourself it will come out to be far less than 2k
so save some money and do it yourself, you will also learn alot abouit your car that way and be one with it

anyways congrats again on the car and welcoome to the board. any more questions feel free to ask away.

 

Thanks tfs95z28 for the PCM tip, I guess this is the next best thing to borrowing a Hypertech PP+ eh? I've heard of guys buying those from Summit or Jegs and sending them back after they were done too, lol.

Anyway, EvilZ28, thanks for the tip, but since I run a website deicated to nitrous I just gotta ask: Were you pulling enough timing and supplying plenty of high octane fuel? And did you ever damage any spark plugs? I'm not trying to be a d**k or anything, I've just never seen a nitrous failure that wasn't caused by a poorly tuned setup (please don't take offense at this, I am still very new to the LT1/LS1 family of engines and could be very wrong.)

Thanks again for the input guys, anybody else?

 

I pulled enough timing as I used a scanner to make sure of spark knock. I also ran a second fuel pump and put on an adjustible fuel regulator and bumped it up to 56 lbs to raise the rate of the injectors to 28 lbs. I also tuned the air fuel rate up for the nitrous with LT1 edit. I then raised the nitrous to 200 hp. I found out from a couple of very reputable shops that the LT1 head gasket just cant handle it. No offense taken. The LT1 is a breed of its own.

 

I think 3.42's for an auto are what you want. Go with an SLP, or K&N CAI. Do a search for free mods also. I think a hotcam kit and a 100 shot will do you nicely and keep everything under 2 g's if you do it right w/ fuel and igniton taken care of. Do some weight reduction too (spare tire/jack comes to mind).

Don't waste your money on pullies, I know they do a lot on sbf's but not for LT1's. Good luck.

 

n20 set up
gears + install
CAI and a cutout

theres your 2k well spent.

After Im done getting my n20 installed, its 3.73's and DR's for me..


then Ill start praying for the tranny/rear.

 

Lt1 pistons are Hypers and are weak. Be very careful hitting a 150 shot.. 175 shot?? Asking for trouble What year 5.0?? Up to 1992 they had forged pistons and could handle a decent hit of juice

 

I hope you plan on putting in a stronger rear end :-) With what your planing ond oing, espeicaly N20 and DR's your gonna blow the thing apart. Whatcha think guys?

 

check out the N2O forum for a bit of info about nitrous on these cars. I know many people that are spraying 150 shots everywhere, and at least one that was doing a 250 shot or something outrageous lioke that on a stock bottom end...power is power its all how you tune for it.

 

Since hes an auto his rear should last quite a while with only drag radials, with slicks and standing on it the rear may twist an axle. I ran a 125 shot on my 93 T/A for 2 years with no problems until my stock fuel pump failed. I ran the Nitrous works wet system along with an MSD 6A with a timing retarder and a set of 1 heat range colder plugs gapped at .040. on the stock motor with basicly what youre wanting to run I ran a best of 11.78 @ 116 mph. The only thing I really had different from what youre wanting to do is I used a 3000 stall vigilantee converter. I was stuck into the low 12s until I got a purge valve and a window switch as well. I set it to hit right around 3500 rpm which was right before the 60 ft mark about 20 feet. I launchd by foot braking it and it seemed to stall to around 2200 rpm like that . After the fuel pump went bye bye I rebuilt the motor and added 6 inch rods forged pistons , bigger cam, ported heads, headers and alot of other little stuff and it ran 12.2s off the bottle and the only time I hit the juice with it (my wife made me sell the Juice) I ran a traction limited 11.1 @ 128 mph on a 150 shot.

 

One of my friends has a 97 WS6 convertible with an auto tranny.

He ran 13.1 last year with the following mods:

BFG drag radials.
K&N air filter.
Smooth bellows.
3.73 gears.
TB coolant bypass.
Relocate IAT.
3" intermediate pipe.

For the nitrous you should ask in the Nitrous forum. I've heard NX and TNT make good wet kits.

Dry kits can sometimes pose a problem with the stock injector locking up under high load.

 

Yeah, I had a 93 5.0 with hypereucraptic slugs and a 150 wet shot (my own kit with a Nitrous Works plate), but I had a 255 lph intank pump, MSD Digital 6+, Jacobs Nitrous Mastermind, MSD Coil, wires, and 2 heat ranges colder plugs, purge, bottle warmer and blanket, fuel safety and oil pressure safety switches, basically all the fixins, and that's on a 302 (cylinder volume does affect how much of a shot you can spray.)

So anyway, I'm thinking a 150 shot with the above trimmings should work fine on a 350.

Anybody know a good electric cutout to buy?

I assume the stock headpipe is about 2.5-3.0 inches, do you guys typically put the cutout after the cat(s) or closer to the muffler?

Thanks again for the replies,
Chris