Hi Guys.
Got a 1991 RS dead cheap. No engine, trans and lots of other things! Enjoying every minute of putting it back together!!
Got a T5 and a 350 (1977 vintage) and will drop them in as soon as the engine has been rebuilt and "warmed over"!
Since all the injection system (TBI) has gone (+ wires and ECU), I am going to keep to the Quadrajet that is on the 350 at the mo, or use another carb (carter, perhaps). Anyway, the whole point of this is not about which carb to use, but the pressure that the stock 305 TBI pump gives out. Assuming that the pressure is 12 to 15 psi at the float bowl needle valve, will this cause problems in lifting it off it's seat and causing unthinkable problems?
If it is too much, what other ways are there of reducing it's output, short of not using it at all?
Eventually, I will go the TPI route anyway, but I want to get the car rolling first. Bear in mind that this is a UK car and all work done in this rainy, soaked, cold country! Thank *** this car hasn't got a sunroof or T-tops!!

PS The yellow '79 Chevy pick up truck in the background has denoted it's engine!

 

Carbs only need 7-8 maximum pressure. Most run fine with only 5 psi.

 

You have two choices. You could rip the fuel pump out of the tank and use the pickups stock pump. Thats a lot of work if your going to swap back to tpi though. You can get a regulator to regulate the 45 psi that the electric pump is putting out down to a carb friendly 5-7 lbs. You just have to wire the electric pump relay to go on with the key. The relay should be in a group of three to the right of the power brake booster. Sorry I don't remember which on of the three it is.

 

Correct me if I'm wrong, but isn't the TBI pump too weak to feed a TPI motor. I thought the TBI pump only put out a few more psi than a mechanical pump.

 

You can get a Walbro 255l/hr electric replacement pump for your car - it's a direct "bolt in" and at less than $100 it's a helluva deal. Then get a Mallory return style fuel regulator (~$75), this'll regulate your pressure anywhere from 3-60psi (IIRC). This is how I have it set up on my TA for my carb and it works fine.

Steve

 

You'll have to go with a TPI fuel pump, TBI gives 7 psi ... the regulator wont do any good ....best thing is to change the pump to a tpi one then get a pressure regulator so you can use your carb and change it to a TPI later ...

 

i just got that Damn fuel pump swapped too!!!!


FCK.... i actually paid labor to have it done... damn....



oh well.... my plan is forming.... thanx guys for the posts. any other tidbits of info?