I have an 85 convert camaro... It org had the 305 ho TPI... I F**ked the 305 all to hell and now building a 383.. now this is were i need REAL-PRO-KNOW WHAT THE HELL THEY ARE TALKING ABOUT help... I have heard so many "yes you can do it" or "no that will never work" or "just have it blessed and run it on holy water"...
Well now it has come down to it... 1) find someone in here that know what they are doing or talking about (ie; someone who has a shop and knows what they are talking about because they do it for a living) or 2) pull the trigger on my 50cal Desert Eagle and introduce my brain to some lead and the outside world.... here it goes... I am replacing the TPI with a DEMON 750cfm speed deamon....
I need to know if i have to drop the tank-pull out the pump- weld a sump to the bottom of the tank- and use an after market pump like the holley red.... OR can i use a AFPR like the mallory 4200 (i have it)... to lower the PSI to the carband and have it work correctly... see i was told the diaphram (if spelled wrong sorry) will not handle the 75 PSI in the fuel pump... plus the lines would not be big enough give the the flow needed for a carb... and if i used the return port on the mallory i could get vapor lock (or something like that) because the fuel will heat up... I don't know what vapor lock does but it dose not sound good...
so to the point what is the BEST way to go from a TPI to a CARB setup... cost in mind but dependability to...
please hurry i have a sssshhhaaakkkyyyy finger and a hair trigger...
No Realy PLEASE I DO Need Some Help....
In Advance Thank You....
DM...


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THE DEVIL SOLD ME HIS SOUL.....

 

If the regulator is rated for the inlet pressure, no problem (I don't know the specs on the Mallory you have). Use the return line to PREVENT vapor lock. The line size will be fine. Someone who works in a shop for a living isn't likely to know the answers to your questions because you're dealing with a hobbiest issue, not the can't-break-a-fingernail-opening-the-hood-on-my-car crowd. You'll need to wire the in-tank pump through an ignition-switched circuit and an oil pressure switch, since you'll be defeating the factory circuit (but keeping the in-tank pump is still the best thing to do - you'll just reroute some of the factory wiring). Vapor lock occurs when the fuel in the line heats up to the point of changing from vapor to liquid - mechanical pumps aren't good at sucking vapor (if this occurs upstream of the pump), and the vaporization process raises the pressure in the line so the pump doesn't pump any more (if it occurs downstream of the pump). An in-tank electric pump regulated with a return line is the best solution to vapor lock.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.93 limited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam and intake, World 305 heads, Hooker headers & y-pipe, 3" Catco cat).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" Hedders, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere w/open diff & slipping tranny. Daily driver while Camaro was being put together.

 

What you're talking about does work for some people for a while, but there is a much easier, cheaper, and more dependable solution.
You can run a Carter electric fuel pump (the low pressure model) that makes about 6psi, and you will not need any type of regulator. It costs just under $60, and you can sell your other pump and regulator. You can use the stock TPI fuel line to feed the carburetor but most people do replace it with 3/8" or 1/2" aluminum line just because it's so easy and cheap to do.
If you go the other route, you may or may not have problems pop up with fuel pressure creeping. The Holley red & blue pumps are not known for their reliability for daily street use. On the other hand I have been using the same exact Carter pump (not rebuilt) since 1988 to service a 10 second car. In my experience they seem to be extremely reliable.
good luck & no need to shoot yourself!
ODB

 

Five7kid.... Thank you for your reply... The Mallory I have is a 4 port AFPR.... How do I find out if it will handle the PSI coming into it.... Also I do not understand what you mean by the following: You said- "You'll need to wire the in-tank pump through an ignition-switched circuit and an oil pressure switch, since you'll be defeating the factory circuit" What does all that rewireing do... And are you saying that in my case Vapor Lock is no big concern....
Again Thank You.... Get Back.... DM


The ODB... To you as well Thank you for your reply.... now with what you are talking about I would need to remove my tank and pull the pump right.... If so I am trying to find a better way around that if possible... i just dont know how to do it myself and i currently dont have the $$ to have it done right now.... I just need some way to make it work for at least a good 6 months or so then I do plan to drop the tank and have a sump welded to it and do it up right.... But you say Carter is a good pump... I will look into it.... ODB if I am wrong in assuming that you mean to drop the tank and replace the pump that way Please let me know...
And again Thank You..... Please Get Back...

DM


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THE DEVIL SOLD ME HIS SOUL.....

 

Well I've been running the Mallory 3-50 psi regulator w/ the stock TPI fuel pump for over a year now to feed my carb. No probs. Can't remember the part number so I don't know if you have the same thing or not. And the pressure from the stock pump w/ nothing to regulate it isn't anywhere near 75 psi, try 25 or so.

The wiring junk five7kid was talking about is to power the pump, once you ditch the computer control the oil safety switch junk won't operate and allow the fuel pump relay to power the pump. I just wired in a lead that's hot when the ignition is on to run the pump. Works fine so far.

I'm sure running a different pump is the best way to do it though. Some people say they just killed the stock intank pump and left it there, and ran a in-line electric pump. I'm looking into to doing that at the first sign of trouble. Ask around somemore to get the further opinions on that.

I don't work for a shop though...

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Ray87Z
-Vortec headed 350.
86 IROC w/ a cammed 305 TPI.
Formerly Ray86IROC.
www.inter-scape.com/Ray

[This message has been edited by Ray87Z (edited April 16, 2001).]

 

I tried doing this on my cross-fire car but the pump acts as a shut-off and doesn't let any fuel by unless it is on.

I did my fuel injected car like this I found the power wire to the fuel pump and i wired it to a switch on the dash and put in an in-line fuse it is a lot easier than wiring hot leads and oil switches, just two wires and you are all set. and nobody could steal it because they would never figure it out because it is a fog light switch.


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I WOULD RATHER PUSH A CAMARO THAN DRIVE AN IMPORT

1983Z28 350w/ edelbrock performer RPM power package with 64cc aluminum heads, dynomax shorty headers, 700R-4 with shift kit, 750cfm carb, edelbrock 3" exhaust system, ASCD SS hood, 16" IROC rims.

future mods:
completely done over suspension, black paint with flames, Hurst shifter, dakota digital gauge package, procharger supercharger.

 

The oil pressure switch is a safety item in case something we don't want to think about happens. Waiting for the jaws-of-life to get you out will be a lot easier to take if you don't have to listen to that whiring fuel pump and smell leaking fuel while the bystanders toss their lit cigarette butts in your general direction...

 

OF course you can run a "return" style regulator with you in-tank pump. Also, do NOT get caught up in the "it's gotta hold 50+psi" talk because that is NOT TRUE! Pumps don't make pressure, restriction does, as is the regulators job. (ie, if you disconnected the fuel line from underneat the car and could turn on the pump, the presure in the line would be small/nil and the fuel would shoot out 20 feet!!!) You don't need pressure to make flow!!!

Your TPI regulator had a 50psi or so setting so that 50psi or so was in the line from the pump to the fuel rails.

When you use your Mallory, set it to around 5psi or so and you'll only have 5psi or so in the same lines. Pump will live FOREVER that way, too, because it can take 50psi forever and is only gonna see 5 from now on. Get it?

Hook the "return" line from the Reg into the return line for the TPI system and you are good to go.

You should check the pressure in the return system, though, to be certain that the return system is not clogged, metered, dirty, bent, kinked, etc... but if it worked w/TPI, it should work with the carb.

 

Hey everyone thanks so much for the help so far.... Question... I have heard alot about cutting the power to the in-tank pump and putting a in-line electric pump on.... Will it or will it not work..... anyone who has done it let me know.... Again all Thank you.... Keep it coming....
DM

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THE DEVIL SOLD ME HIS SOUL.....

 

What's up,man? Just use the in-tank pump!!!!

 

Seems to be alot of differing opinions and findings w/ running an inline w/ the intank pump just turned off. Most say it doesn't work but at least one or two people here were doing it...

But if the Mallory Regulator you have is the same thing as the one I purchased from Jegs you shouldn't have any problem w/ the stock in tank pump. Like I said one year going strong on mine...

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Ray87Z
-Vortec headed 350.
86 IROC w/ a cammed 305 TPI.
Formerly Ray86IROC.
www.inter-scape.com/Ray

 

The inline Carter pump should pull fuel through the stock pump with no problem at all for normal driving, but if you're planning on making over 300hp then I'd suggest removing it and replacing the pickup tube so there is no restriction.

stock pumps do NOT last forever and you would eventually be pulling the tank to replace it one day anyway. It's not a lot of fun no matter when it happens, but even less so when you need the car to get to work or you're in the middle of a long road trip.

 

I Guess I an in the crowd for leaving the in tank pump, No i'm not going to get in to all the arguing eithor. BUT if you do decide to put a inline pumo in it will pull through the in tank pump. My holley Blue pulled through my stock pump for about six months, Till the stock pump fell off the tube it was on. I made my pick up from 3/8 brake line, and a piece of rubber gas line hose clamped both together, And it has been working fine for the last 6 months. It might not be right but it is working for me.
Later
John

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82 Firebird,408,Dart Iron Eagle 215's,Cam 229/239, .498/.520,TH350 Tranny, 750 Speed Demon carb, Hooker Headers(I.E. POS) Manual steering, Also a cowl for the big hole in the hood.
Shooting for low 12's.
Check out my birds new home.