started my car today after installing rpm pefromer intake and 750 quadra jet. runs so much better then with that tpi crap. haven't driven it on the road cause i have a bunch more little things to work out. i have a stupid coolant leak on one of the front bolts to the manifold and i can't figure out why so i'm just gonna get new gaskets. other than that i have some wiring to do for my fans and it ready. What kinda times can i expect with my mods?

91 firebird formula 350 L98

long tube headers

rpm manifold

750 carb

emissions and ac delete

 

whats the specs on the cam and heads?

what is done to the exhaust?

what rear gear do you have?

auto or 5 speed?

i dont know anything hardly but they will wanna know that stuff

 

headmen long tube headers. running open headers for right now. stock 3:23 gears, stock 700r tranny, stock cam and heads. when my car was running very poorly with the tpi fuel system i ran 15.2. the car runs eight times better now which i think will eliminate the old problem i had plus i should get a little bit more power from the manifold and headers. i personally think it will run at least 14.5. thats what it should had ran stock, but like i said the crappy tpi system had problem after problem and my car ran really bad.

 

My L98 with RPM intake, 750 VS carb and hedman shorties went like 14.2 @ 98mph

 

ok i have a problem and i need some help. i did my research on here and i read that some guys kept the stock fuel pump in the tank and ran an electric one instead. i tryed this and i'm not getting enough fuel from the electric fuel pump. its a 4psi pump. how is this done cause i'm running out of cash and time. would a higher psi electric pump work or is an electric pump not strong enough to pull from the gas tank. as far as i know there are no elctric fuel pumps that mount in the tank. the one i have is a in line pump which i read would work on this site from ppl that have done what i'm doing.. so my question is would removing the stock in tank fuel pump fix my problem and if not how the hell have others set this up before?

 

If you're using an inline pump then you must have the existing pump in the tank turned off. The existing pump can supply 250hp worth of fuel at 45 psi. It can supply plenty more at 6 psi. You need to install a by-pass style regulator. Here's a picture of mine. I have all the fuel flow I need. It's JEGS part#793-30-900. It's a bit pricey but it lets you use the very good pump already in the tank. This assumes that the pump in the tank was not the reason the TPI system was running crappy. Don't forget to install a new fuel filter just in front of the rear axle.

 

so you got a regulator and kept the stock pump? how does the bypass regulator work and how does it install?

 

It's just like the pressure regulator for the EFI except much lower pressure. The fuel comes in at the bottom and the excess flow above the pressure setting returns (to the right) to the tank. Top hose goes to the carb. Electrically all you have to do is wire an ignition key+ to the fuel pump relay to make it run when the key is turned on. (like one of the ones that used to go to an injector, it's got it's own fuse) Hardest part is getting the fittings that will hook up to the hose fittings. I used the existing hoses that went to the TPI to connect to the regulator so I would have two less hoses with clamps on them. (Notice the dual hose clamps on the top hose to carb in this pic and the armour on fuel hoses, I don't like fire) That's all there is to it. All the fuel you need at a rock steady 6 psi. (or whatever you choose). Kinda makes installing a second fuel pump downstream sucking on one that's turned off seem kinda silly huh?

 

If you really wanna wire it well, do it to an oil pressure switch. This way, no oil pressure=no more fuel=no more running.

 

Actually both would be best, which is what the factory did. If the oil pressure thing would work the cars wouldn't have the relay. If the car runs out of gas the starter turning the engine over might not make enough oil pressure to ever turn the pump on. This would be the pits. Oil pressure switch should be hooked to either a biga$$ light or an ignition wire under the driver's seat

 

Actually good point. I knew about the gas thing, just figured I've never run outta gas yet so I would take my chances I will however, forget it and wire it to the ignition. Good suggestion

 

so i'd like to determine my problem before i make a move. heres my situation. i did not remove the stock fuel pump from the tank. instead i unplugged it and placed a inline electric fuel pump where the fuel filter goes. it's a 4psi pump. now its all wired and works, but after a while the car runs out of fuel when its running. is it that the new pump can't pull fuel through the one in the tank? is it a must to remove the pump in the tank? to clerify my questions:


Is my new pump good enough for the job at 4psi?


Or is it that it can't pull the fuel past the old pump in the tank, and the fix is to remove the in tank pump?

 

That.

 

thats what i'm starting to believe myself, but the only thing that makes me question that being the problem is that. others on here say i should be ok just unplugging the pump. which i have. i guess i'll pull the stock pump from the tank and if i still have problems then i know its the electric pump i installed.