I have a 87 Camaro that came from the factory with a LG4 motor that used an electric fuel pump. When I got the car the LG4 was gone and a 350 carbed motor was in its place. The in tank pump wasn't being used only a mechanical pump. Now I am running a TBI setup and I am wondering if the LG4 in tank pump will support the TBI motor? The reason I ask is becasue I believe I read somewhere that the LG4 carbed motors used both a in tank electic and a mechanical pump, which leads me to the question of how much pressure the intank LG4 pump puts out. Any input would be appreciated.

Thanks

 

as far as i know, the LG4 has 1 fuel pump and its mechanical. passenger side by the AIR pump....

ps. why go from carb to TBI????

 

no it can not

that pump puts out about 5-7 PSI

TBI REQUIRES 13-15PSI

oh yeah, i'd stay with a carb too

 

keep the carb! TBI in my opinion sucks, TPI looks good and peforms very well with light mods but, falls short in the big HP numbers so if you got carb keep it

 

I have the LG-4 in my Z28 & have replaced the fuel pump on the right front part of the motor. I was not aware that there was anything like a pump in the tank except in the TBI & TPI cars!

 

Ok I should explain a little more. That 350 carbed motor that was in my car is actually a ZZ4. It came out and now has a miniram which will be going into my 1992 RS which had a 305 TBI from the factory. The TBI motor from the RS is going into the 87 Camaro I have. That is the reason that I am using TBI becasue I have the complete motor, sensors and all dropped into the car already. It would be way to much work to take that stuff off and install a carb which I don't even have.

So back to my problem. If that pump isn't going to put out enough PSI to run this TBI motor than will I have to add a mechanical pump to the block? Will having the 2 pumps like the LG4 did increase the PSI to let the TBI run correctly? I could always drop the tank (what a pain) and put a TBI pump in, but I would rather install a mechanical one to help the in tank if I can.

What do you guys think?
Thanks

 

No...I had an 84 Firebird V8 with LG4 engine...after searching around I found that the the L-69 engine of that year had a helper electrical pump simply to help overcome vapor lock issues of a carbed engine.

You need to use an in-tank TBI pump...simply put...to accomplish your goal.

Your Miniram motor in the 92 certainly needs more than a TBI fuel pump to make it work....so use that...

And yes, it will be a huge PITA no matter what option you want. To use the TBI setup, you need a TBI fuel pump and one that is in the right range as well. If you put in a pump with a MUCH higher capacity, then you will need an AFPR to get it back to the 14 psi you need.

HTH,