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TPI tuned port injection 85-92 Chevrolet multi point injection. The LT1 would replace it in 92 although the Z28 and firebird would use it until 92.
SPID label is on underside of glove box door.
Yep you nailed it in both posts! I think it was worse years ago. These days some are just happy to have a vette or whatever. I find it hilarious most c4's were auto. No question my car would be more fun stick, but it has a certain character to it as auto. Now a stock auto is just plain lame and anyone driving one is a pansy!
Be careful, be careful!
Don't enrage, callin' "pansy"! There are a few lurking about with thin skin and soiled diapers!
He means the lid on your console. I put 3.07 gears in my 94 and made a big difference. Much snappier around town and lost little, if any, highway mileage. I still get 25/26. I bought a used 3.07 center section from a member here and put it in myself.
It's a 94 coupe base LT1. Completely stock no mods whatsoever. I'm not sure what gears I gave in it now, someone on this site told me it would be on the SPID sticker somewhere on the car but I can't find it. I'm just gonna assume I have 2.59 . Would a change to 3.07 be more logical,cheaper and more importantly little more fun. It's my first Vette ever and I'm not complaining or nothing but even with the ASR off I can't even do a hole shot. I'm gonna be 50 this year so I'm not looking to beat the snot out of her....... Just wanna have a little fun is all. It's a car I only plan on using it perfect weather other then that it's in storage
If you are turning like 1800-2k at 70mph you might have 2.59. If you look at the metal tag on the rear end it might say 2.59. If you vin has GM1 it might be 2.59, if you lift the car and count the turns on your drive shaft and it comes out to be 2.5 turns or so for a full wheel rotation you might have a 2.59.
If I recall a '94 you can reprogram the speedo rather than change gears.
Technically all c4's 85-96 were TPI, but the LT1 is the short intake runner and more power, the L98 is sometimes referred to as the TPI.
You will know if you have a 2.59 it will be like an old 70's car basically. A 3.07 was the performance gear and kind of snappy. Still a lower gear really wakes these cars up and feel the seat of the pants..
Last edited by pologreen1; Apr 17, 2019 at 10:09 PM.
It's a 94 coupe base LT1. Completely stock no mods whatsoever. I'm not sure what gears I gave in it now, someone on this site told me it would be on the SPID sticker somewhere on the car but I can't find it. I'm just gonna assume I have 2.59 . Would a change to 3.07 be more logical,cheaper and more importantly little more fun. It's my first Vette ever and I'm not complaining or nothing but even with the ASR off I can't even do a hole shot. I'm gonna be 50 this year so I'm not looking to beat the snot out of her....... Just wanna have a little fun is all. It's a car I only plan on using it perfect weather other then that it's in storage
You could go to GM and get a total printout for all the features you have with the VIN.
I'd say that if you don't do much more to the car, maybe 3.45 or 3.54 if they offer it for that hole shot
my LT1 with the 3.54 gears is a blast to drive on all levels. from stoplight to stoplight is accelerates hard and from a start will break the tires loose if you turn the ASR off. at highway speeds (70mph) it turns 2250 rpms and gives me around 20 mpg. in addition acceleration from 70 to 90 is brisk. I see no down side unless you want to drive 150 mph. I have fun with the manual cars, every time they shift I pull ahead. cost for me was $2000. but if you do it yourself about $500.
"TPI" means tuned port injection. Here in this thread, it refers to the L89/L98 engines, in other words "not an LT1/LT4." Although I believe the LT1/LT4 engines have tuned port injection also...? But they don't have the long intake runners like the L98. Many other differences between these engines but I am limiting my comments to the fuel/intake question.
"TPI" means tuned port injection. Here in this thread, it refers to the L89/L98 engines, in other words "not an LT1/LT4." Although I believe the LT1/LT4 engines have tuned port injection also...? But they don't have the long intake runners like the L98. Many other differences between these engines but I am limiting my comments to the fuel/intake question.
Actually LT1/LT4 engines are considered MULTI PORT FUEL INJECTION(MFI)
Last edited by Y-bodluvr; Apr 18, 2019 at 11:19 AM.
Ieven with the ASR off I can't even do a hole shot.
You most likely have 2.59’s my 95 I had 3.45’s 2800 stall, shift kit, tune and some bolt on/free mods I had to upgrade to 315 Nittos and it could still light those up if you mid yours similarly I’m sure you will be more than happy..
I don't think they suck. But to make them not suck even more install a shift kit, and maybe even a trans brake. I put a shift kit in my '71 LS5, TH400, shifts hard and fast and lights em up in every gear. Note, this will shorten the life of your transmission but the fun makes up for it.
I was thinking of going with the 3.54s from Zip corvette and using my rear with 2.59 gears as my core(refundable $400). Will that work? Or do I have to have a 3.07 rear to move up to the 3.54s?
What this means is at any given speed, you have more force to accelerate, but you are probably concerned about highway speeds as well.
3.54 at 70mph is about 2300 RPM (In my 6-speed I think this is about 1900 LOL)
3.07 at 70mph is about 1980. RPM.
Here is an idea of a WOT run with a 3.07 Gear:
And Now with the 3.54 Gear:
For S&G's, here is a 4.10, that would require about 2600 RPMs to run at 70mph
If you were tracking it more, we would talk about the number of shifts, anticipated trap speed, traction and a whole host of other things. If you were a weekend warrior I would be all over that 4.10 until you had a trap speed over 115mph (Roughly 425hp to the wheels). I have a supercharged LT4 and don't put that much power down.... yet!
Last edited by vette196; Apr 18, 2019 at 12:10 PM.
Depends.....if I had to sit in traffic all the time it would be an auto. Love sticks but they suck in bumper to bumper.
Had both auto and stick, if I get another C4 it wont matter which, condition will make my decision. Not like Im after something fast anyways, just a cruiser on the cheap w/working AC, kinda like the first one.
If electronics dont bother you 8-9k can get you a pretty nice C5 these days.
