Question: Frankenstein C4

[DocHook]

Hello everyone, I am brand new to this forum. I am 71yrs old and bought a 1990 C4 project. I used to be a good mechanic back in the 70's and mid 80's I always wanted a corvette but being on a fixed income now I couldn't spend a lot of money for a project. I wanted something to tinker with. Well I got it! I paid $900.00 for my C4 with title. The body is straight but needs a paint job and a new top. Interior is nice, I purchased from a very nice guy that has a lot of old cars but he didn't know much about it. I apologize for getting a little long winded here yet I think a little background is necessary. Okay, got it home and opened the super heavy hood expecting to see the spider looking TPI, nope mounted atop was later model 94+ LT1 intake. I don't know what I have except maybe a yard ornament. It appears to have ran judging by the oil film covering the motor. Was told the transmission went out so the car was parked (I got another Transmission with the car) The reason I call it Frankenstein C4 is it may have the LT1 intake with yellow injectors yet the distributor is behind the intake and it has a belt driven waterpump, no optispark. I didn't know it was possible to bolt an LT1 intake on a l98 motor. Maybe they put LT1 heads on it? Who knows with enough orange RTV you could make anything fit. I am about a 12 pack away from bolting a new intake and carb on it. I just need advice on what I have and will it work or is a carb in my future? I will try attaching some pictures. Thank you everyone and let me know if I should start ordering some nice annual flowers.

 

[Tom Bryant]

Welcome to the CAC.
That is interesting. I haven't messed with these much. It looks like the Tuned Port throttle body is in place. I'm wondering if all of the fuel and electrics from the Tuned Port are in place but just the LT1 intake casting has been changed. Might have been an attempt at a better flowing system. I think I'd change the fluids then check all of the basics on this, just like it was Tuned Port, and see if it will run.

Tom

 

[DocHook]

Thanks for your reply Tom, it appears that this was some long forgotten conversion kit. I think I will attempt to get it running as you suggest, but I purchased an original tpi system just in case. You never know? In case I go back to TPI I will send Egore to find it a new brain.

 

[DocHook]

Welcome to the CAC.
That is interesting. I haven't messed with these much. It looks like the Tuned Port throttle body is in place. I'm wondering if all of the fuel and electrics from the Tuned Port are in place but just the LT1 intake casting has been changed. Might have been an attempt at a better flowing system. I think I'd change the fluids then check all of the basics on this, just like it was Tuned Port, and see if it will run.

Tom

This c4 is a bit of a hot mess, but I am having fun with it so far. I bought a new top, battery, and ignition lock cylinder for it. The keys are lost so I will have to get with a locksmith for the proper key resistance or maybe a VAT bypass. I have fun tinkering with things. I found a used tpi setup on marketplace for a 100 bucks just incase that lt1 manifold is not viable. Thanks!

 

[Tom Bryant]

The TPI intakes weren't known for flowing too well in a high-performance state. There are all sorts of runners and base plates made for the TPI system to increase performance. From what I have been able to find, the LT1 casting is better performing than the TPI above 5200 rpm but the TPI way outperforms it in torque below 5000 rpm and also shows better hp below that point. The TPI would probably be a better around town and normal driving intake if it will bolt on. I watched a video where they removed the LT1 intake and mounted a TPI just for comparison's sake, and the TPI had to be modified to bolt on. It could be that your heads have been changed too. Check the ECM to see if it is for the TPI or the LT!. It looks like you will have some fun tinkering with it.

Tom