Hey guys i just came across this 92 corvette with a 6 speed. I will upload pics when i can. Overall the cars runs nice and looks very good. It has 114K miles which i think is very low for its year. Any advice in taking car of an lt1? Or specifically a c4? It is stock, but apparently the owner but a "borla" exhaust system. He also mentioned that the car had a "hyper" chip. How can i verify if thats true? When i want to start modding where should i start? Iv heard these differentials arnet that great.I have so many questions and hope you guys can guide me through it. Any input would be appreciated guys, thanks.

Joel

 

"hyper" could be "Hypertech"...not regarded as any "performance" improvement.

They were typically hand held device you plug into the data port and are vehicle specific per VIN. you could change things like gear ratio, tire size, shift points and supposedly "performance" tune and load that program and your stock one would be stored in the device if you wanted to return to stock. Don't know if the 92 ones were HH or a "in-line" deal like the JET ones were. If in-line it would be attached to one of the cables of your pcm

 

thats not that low of mileage, I'd change the tranny fluid and diff and carefully inspect everything before modding anything, look for oil leaks LT1s are notorisous for them. Hypertech as mentioned, sucks get it off your PCM asap. Optisparks are supposed to be changed at 100k miles i believe so might want to look into if it was done, but if not its best not to mess with a working one anyway. other than that regular oil changes keep her running good!

 

Like mentioned above with a car that old with so few miles, change all fluids, engine, trans, rear diff, coolant, flush brakes, and then do a tuneup to get you a nice starting point with NGK TR55 plugs, and some Delco or Taylor or MSD wires (people bash Taylor, I've used them for years with no issues). Once that's done, rev the snot out of it and see if you get any misfire up top (> 5000rpm) and try to uncover any other weak points like an old failing opti, fuel pump or coil. If no issues arise, do long tube headers and full exhaust behind them. Then a cold air intake of some sort, then a mail order custom tune.

Seeing as your a newbie, some key words to stay FAR FAR away from that you may hear old school small block guys say:

LT4
Vortec
Hypertech
Edelbrock
Adjustable fuel pressure regulator
Bigger MAF
383
CC306

If anyone gives you any advice that includes any of those words, kindly nod and dismiss everything they have said.

 

x2 and I too use Tayor wires with much success. oh and free mods might be something worth looking at, TB bypass for one, ICM cooling mod is free and easy and helps keep the ignition control module cool.

 

Given it's a '92, there is no PCM. It has an ECM, which means the Hypertech is a chip or piggyback. To use it, the previous owner would of had to replace the stock t-stat with a 160 degree. The piggy back didn't really do much. I think it turned on the fans earlier and enriched the a/f slightly. To get to it, flip your ECM over and you will find a small panel. Take off that panel and you will see the piggyback.

Since you have a manual, the rear is a Dana 44. Plenty strong enough to handle up to about 450rwhp. The weak points would be worn u-joints on the half shafts.

As for modding, it's like any other LT1. Only difference being you will be paying 2x as much for parts. The dreaded corvette tax.

 

dont be like me and buy a supercharger and cam as your first mod

 

Dont put a 383in it either you might faint from the extra torque

 

When i bought the car the owner gave me a fat binder with everything about the cars history with replacement parts and oil changes. He even gave me the original sticker on the window when he first bought the car in 92. Optispark was replaced at 98k miles. No leakes at all and engine runs flawless. I checked her fluids mines tranny fluid and rear end. I would like to start with some nice headers and a full exhaust system...my issue is that i live in california, not sure what i can and cant get
I would also like to do gears as well for now.

 

LOL california your screwed. just dont get shorty headers. im not sure if kooks long tubes w/ catted pipe are legal there but they are about the nicest headers.

 

What is wrong with a 306? If you say "lazy lobes" you are the one who needs the kind nod and dismissal. That cam along with a good set of heads was responsible for getting many f-bodys anywhere from the high to low 11's in the mid/late 90's. What's wrong with a 383 again?

 

Dougs makes a smog legal 1-3/4shorty they are nice and fit well

Hotcam or something similar with a good tune will pass smog

Have used that, ported heads/intakes they run pretty good for what they are
Actually an aftermarket set is the way to go. By the time you pay to put good seats larger valves porting etc etc to do it RIGHT youll still have an inferior set of used heads and spend about as much as a real good set that are new and make better power. You can easily get an honest mid-high 3xx at the tire and be legit, good for a low 13/high 12 in crappy Ca air with a sticky tire on it.

You got the D44 rear end they are plenty strong the ZF6 is about indestructable just keep your hydraulics (slave etc)in good working order.
If shifts get funny thats usually the problem.

 

What he said ^^^^^^^^^^^^^^