LT-1 Conversion and Fuel?????

[Mciamp99]

For all those who have put a late model LT-1 into a C-3, how did you handle fuel delivery? I am currently using a 96 pump in my tank, but am having some problems with this set up. Is anyone using the same, or is anyone using an external Pump? If you are using an external pump, which type and where is it mounted? If internal, what tyoe and how is it mounted? I think if I can resolve my fuel delivery problem I will be all set so I am hoping the CAC can help solve this problem for me.

 

[Last Ride]

Mine is in-tank, but I am not sure what brand. I know it is an aftermarket unit, and I have never had any fuel delivery problems. Sorry this is not of much help! Good luck.

 

[patsnitrovette]

ive used both setups,i had a 89 pump on the end of my stock sending unit,and it was loud so i removed it and went with a holley inline pump mounted to the frame right between the tank and the body witha fuel filter in front of that right after the sending unit feed line.The inline is a little quieter but i have to make a heat shield cause its right above my flowmaster mufflers.What kind of problems are you having with the intank one,is it running fry when youget low on fuel?Ive seem some guys make a sump in the tank to fix that,but youll have to remove the tank and have it welded somewhere.

 

[Mciamp99]

What is happening is that the fuel pump is shuting off after some amount of time. The time varies with no rhyme or reason. It is not the PCM shutting it off, or the relay. It has power when it dies. I also have Fuel Injectors and spark, but no fuel pressure. The motor will be running fine then the pressure drops and it stalls. After 20-30 seconds the pump will kick on again. I am on my second pump and can find nothing wrong in the lines, wiring or anything else. It is like the pump is getting hot and then quitting. I am close to the end with this project but frustration is starting to set in. I think if I go with an inline pump it would solve my problem.

The only other thing I can think of is that the Pump on C-4's is set vertically on the sending unit. I have it set horizontally on the bottom of the tank. But it also ran for several months and I had driven it about 65 miles before this problem occured. I have also changed the relay and pressure regulator, I am sure it has power when it quits and I am sure it is not being shut down by the PCM.

 

[patsnitrovette]

I know that the way my 89 pump was sitting on bottom of the tank also horizontally,it worked fine but just loud being on the bottom like that.

 

[offshore]

It wouldn't be the first time I've seen a new pump go bad!

 

[Mciamp99]

Pat

Do you know which Holley you used? Did you also use manual regulator or did you put one inline as well? I would be interested as I am giving my intanke one more try this weekend then going to external route. Thanks, Michael

 

[patsnitrovette]

truthfully not sure which one ,i think its a older one it was new when i bought it but not in a package,the newer holleys look different then what i got,im using the factory regulator and works fine.if remember right 13-???? only thing is last night it gave me trouble,wouldnt build pressure,till 6th or 7th time trying then it was fine,now today it fired right up,thats the first time its done that in a month since i installed it.i think im gone to install the intank back in this weekend and run both,one for nitrous(inline) and the intank for normal running,but i need to quiet it down some,maybe ill wrap it in rubber.

 

[wichitacorvette]

I just finished my tpi conversion... i used and external and took off the rear bumper and mounted it to the frame between where the taillights go...... worked out nicely........ up high to be well protected yet low enough to get good fuel flow ill post pics later tonight. i used a pump that came with my FI kit i got from affordable-efi.com and it seems to be a great pump, not too loud but still keeps pressure right on point.