I bought a 97 z28 recently. It has equal length headers, off road y pipe and flowmaster cat back. Still has original shifter and original air box. Service engine soon light is on (o2 sensors?). I dont have a garage at the moment or really any tools. Would regular exhaust shops check/install those to see if the light goes off? Car runs great but definitely has a fat tune on it. Kinda dont want to drive it as im afraid to wash cyl walls down. Dont smell gas on the dipstick tho? Any advice? Most appreciated. Thanks

 

Drive it to autozone and have them check the codes.
O2s are fairly easy to replace.
Save some money and do them yourself.
But yes, an exhaust shop can do it.
But make sure you research the code first.

 

Thanks for the reply. Money not issue. Right now its more of a domestic issue. I dont even have a floor jack that will roll underneath the car! I have gotten a hold of a shop and told them what i have and they have experience with f bodies. Some guys are saying i may need an extension harness because of the 3" ory? This is my first f body for like 9 years! Ive been into corvettes as of late. Ive had a prior 93 z and a 98 z.

 

Is there any certain type to use? Like oem or high dollar aftermarket? Headers, ory, and catback are only mods on the car. Everything else is bone stock. Mods here on out will be done by myself so, there wont be any ???

 

Get OEM (AC Delco) sensors.

Trust me on this.

KW

 

Thanks man, will do!

 

If he didn't extend the O2 harness then they might not be plugged in. Be careful of shops, the LT1 is the Harry Potter of the F body world, it lives under the stairs and nobody knows about it. Make sure the shop knows LT1s.

 

Yeah thats a good ? I just bought the car a month ago and the guy i got it from said the o2 sensors were either not plugged in or ? He just had the headers, ory, and catback installed a couple days prior the car being put up for sale on cl. He runs a marine biz and something happened where he had to sell the car asap. He had it on cl for 6k for couple days then it went to 5k for couple days then it was 4.5k lol. I called him and said ill give ya 3.5k today for it and he said ok for that day only. His wife wasnt happy about selling it as he had just spent a lot of money on the full exhaust and sound system. Its a cream puff car that has 118k miles and everything else is bone stock. Even still has orig shifter and air intake. I have a mgw shifter, hurst leather ****, and bronze shifter bushing coming today.

 

A reputable shop down the road from me who it seems works on performance cars as i see corvettes, mustangs, and some loder muscle cars sitting there from time to time tell me that they have some experience with 4th gen fbodies? I guess i will find out when i take it there to see whats going on?

 

I want to do a cai also. Right now im leaning towards the trick flow elbow in black powdercoat with the slp cai? I had the moroso cai and a 1le elbow in my 93 z28 i had 10 years ago. My 98 z28 i had 9 years ago had a slp lid. From what ive seen and heard, any ole cai pretty much gets the job done? After the cai, i either want to get a handheld tuner like a hypertech or ? Or should i just get it dyno tuned?

 

Im also on the fence about a 160 thermostat? I read some lingenfelter books i have on lt1s and they said that gm has them run a little hotter for a reason? Like some kind of parasitic loss retention through the higher temps? Would a 160 therm cause an issue if the manufacturer wanted them to run at a higher temp or was it just for some kind of emission or gas mileage reason? Been looking at the slp 160 thermostat anyways and the car is not a daily driver but although the price point in which i paid for the car and the fact that its not really a rare car or anything i would like to drive it more than i do my 03 ZO6.

 

Yep, yet another question. Ive been told that before i can take it to the dyno that i should have a fuel pressure regulator on the car as they will need to adjust while tuning? Im looking at an aeromotive fpr and an aeromotive fpr gauge? Anybody with any experience on this?

 

MAX...

First sort out the 02 issue. AC Delco only on those. If you can turn a wrench and connect a plug....you can and should do this yourself. With the long tubes you likely need extensions so do a search on where to get those. If the headers do not have bungs for the 02's to screw into than you need to go to a muffler shop and have them weld them in and at that point just install the 02's

Don't run a 160 stat unless you have the PCM tuned for it. A mail order tune for a stock motor with CAI, headers will be fine. You will need to bleed the cooling system if putting in a 160 stat

Stay away from Aeromotive anything. If you do need a adjustable FPR get a BWD (Borg Warner) one which should be able to get at local auto part store. It is a direct fit for the OEM one

 

Max97z28, I just bought a 1996 Z28 (my 5th f-body) and here are some thoughts.

My car came with a K&N CAI. It is nice, fits well, but getting the filter on is a PITA. I took it all apart to clean it and it was a 2 person job to get the filter on. One to hold it the CAI from the top, the other to push the filter on. I put a Moroso CAI on a 1995 I owned and don't remember it being that difficult to get the filter on. I think if you have headers/exhaust a CAI is mandatory. More air in + more air out = more power. You have the exhaust end of it taken care of.

I installed an SLP airfoil. Don't know if it works or not. But it was cheap and easy to do so why not?

I installed a 160 thermostat. Easy enough to do (you have to take the elbow off the throttle body to get to the thermostat housing) I also reprogrammed the fans with a Hypertech I bought off Kijiji. I would suggest draining some antifreeze before install. Some came out when I installed it, and I didn't think it was much until I moved the car and there was a substantial puddle below the car. Thankfully the opti didn't get wet. Also, I didn't have to bleed my system for some reason. It was fine. After I put everything back together I ran the car with the rad cap off for about 15 minutes. It "burped" a few times while I did that so I assume it was letting air pockets out.

On a sidenote, the LT1 came with a 180 thermostat from factory so going to 160 isn't a stretch but is pointless unless you reprogram the fans. Also, some say your oil will not get hot enough to burn off contaminants but some say it does. I think on short trips it would be an issue however it would be with any car not getting to operating temperature. But it def runs noticeably cooler with zero effects as far as I can see. I believe my car has the intake manifold oil leak, and I haven't smelled that slight smell of hot oil since I did the thermostat, however it def does not fix the problem. I think the engine just does not get hot enough to burn the oil seeping from it. Could be my imagination, too. lol

Some say your fans are running all the time but I didn't notice it at all. When idling they come on more often but not much. That is my experience, some say otherwise.

As stated, I bought a Hypertech off Kijiji. Some like them, some don't. It depends on what you are doing. If you want to reprogram fans, get new gears, different sized tires, change shift points and firmness, rev limiter, I would say it is fine. The nice thing is you don't have to send the PCM in to anyone, and you can change it back to stock if necessary. It comes with a tune and some say it works, some say it doesn't. I understand that if you install the 160thermostat in conjunction with the Hypertech tune it "may" work. Only one way to find out, which I will do when I change my tune with a rudimentary before/after with a g-tech. But I don't think it is the answer for a serious tune if you get heads/cam etc. Not a chance.

I did the throttle body bypass. Went to Napa and got a 1/ 8" barb fitting, two #6 hose clamps, and two nipples to cover the openings when you remove the hoses. Good luck. I never swore so much before. The drivers side is easy to take off, the passenger side was a bit**. Some people cut the hose off but I refused to and payed the price with lots of swearing, skinned knuckles... also, I didn't lose any rad fluid but I did use a turkey baster to take some out of the rad just in case.

If your car was mine, the first thing I would do is get that check engine light taken care of first. The hypertech can read codes, or you can buy a cheap code reader from Amazon for under $20. Or take it to someone to read them but I want to do it myself so I know exactly what is wrong and what to expect when I take it to a mechanic.

 

Ok guys, i appreciate both responses and especially appreciate the responses being specific. I will get me a set of ramps and a floor jack that will slide under the car and get that thing up to where i can get my big *** under there to see whether those headers have the bungs or not?

Only thing i can see from looking under the car are the collecters hanging down on each end and they are welded to the y pipe.

My buddy has a 91 gt he bought new with 21k miles that has 1035 rwhp! On 110 oct. He told me today he has an actron scanner of some type that we can use to diagnose the codes.

Im just excited to have gotten another fbody to play with and mod as my corvette has very low miles and i want to leave it stock so, i im pretty excited!

There again, i appreciate the responses and advice and i will post what my findings are when i get the work done.

 

DO NOT waste the money/effort/time on an adjustable fuel regulator on a near stock, naturally aspirated engine.

Hell....I still have a OEM regulator on my 475HP (or so) 396ci solid roller LT1/4.

Seriously.....it ain't needed!

KW

 

What he said. Adjustable fuel pressure regulators are used more often when they're not needed than when they are.

It will likely cause you more problems than solve.

 

Yeah it will be a while before im at that level (396)! So, i wont worry about it then. Just want my car ready to get a baseline with what i got. Thanks guys.

 

If someone tells you that a adjustable fuel pressure regulator is needed for tuning a setup like yours, Run from that shop!!

 

I got under the car and found out the o2 bungs are on the collectors and currently they are capped off. There isnt any o2 sensors at all.

Elsewhere in this forum, some people are recommending going with the oem ac delco o2 sensors for a c5 corvette rears and im under the impression that they already have the extended harnesses with them? Shall i get those or just get the original ones for my car and extended harnesses?

I installed the MGW short shifter yesterday and also put in the bronze shifter bushing along with a camaro ss leather hurst shift ****. Its awesome!! Only problem i have is that its kinda hard to get into reverse? Anyone else have this problem? I noticed that the under the console shifter boot was kinda tight. Maybe i should have cut a little bit off it to better acclimate the new shifter because of its design? Anyways, thanks as always for any input and advice.