I would of replied to the last post, but it was locked.

I wonder at what point yall had to do something about the fuel pump in your carbed cars.

I used the stock fuel pump in my 92 firebird 355 tbi with ported and polished vortec heads and a blower, and never felt it was starving for fuel. Not sure how much power it was putting down, but i did have pre blower dyno's over 320hp at the engine.

I am now putting a 383 stroker in the same car that will have a 800Double Pump holley carb, 215cc dart heads, and near 600 lift solid roller cam. We are expecting close to 500hp/500ftlbs.

I'm guessing the poor tbi pump definitely wont support this? I have a holly blue pump, can i safely just wire it inline with the stock pump, or do i need to try to remove the stock pump all together?

My understanding was that the tbi pump can sufficiently keep the bowls full enough unless you stay on the gas for a long time... Anyone offer any input?

Thanks,
Shane Buss
1992 Firebird
2001 Trans Am, hotcam,nitrous, 3000 stall converter, nittos
(p.s. my shanebuss account is screwed up if anyone wants to know why im using this one)

 

I replaced my TBI pump with a Walbro 255 lt/hr direct replacement pump when I dropped my 383 in. 750 Holley with V/S, Sportsman II heads; worked out to around 460HP. I didn't want to risk my new engine on something as simple as a fuel pump that's all. Since I was looking at turbocharging down the road, I wanted to make sure that I'd be good for a while. I have no idea about adding another pump inline, but for peace of mind, I'd swap out the in tank for a decent pump - OR - pull out the in tank and go with one of the inline fuel pumps recommended over on the Power Adder board.

Just my two cents,
Steve

 

Isn't it a royal pain in the *** to pull the stock fuel pump out?

 

The only way the tbi fuel pump will hold pressure for you is with a vacum afpr. I just had a regualr afpr and it would drop to zero psi at wot.
bought a mallory vafpr and it holds steady.

 

That is odd.. Mine doesnt drop to 0 now, nor did it when i had the blower...

I have a normal FPR inline right before the carb, and the fuel pressure seems steady.

I dont have a guage in the car, but i would know if it was dropping to 0...

How much HP you expecting the stock pump to support?

Thanks,
Shane

 

Well, compared to swapping out motor mounts it was a piece of cake. I was replacing a rear end at the same time so I dunno. I didn't think it was that bad. Taking my time it took an afternoon for me and a buddy.

S.

 

You may want to consider going with a 3-port fpr so as to not burn up your pump. As far as replacing it goes, it is much easier if your exhaust isn't in the way. I've dropped the fuel pump on my car twice, and learned a lot. It is kind of a pain in the butt. The GM engineers really outdid themselves screwing that one up. The two tricks that I learned from doing it are: 1)Jack up the rear-end of the car as high as you SAFELY can. This will help.
2) You're going to have to twist the fuel tank for it to drop out and to put it back in. Have someone grab the filler neck to help you guide it out and back in. This is very helpful. That's about it. After you do it once, it's not so bad the second time. Good luck!