Just got off the phone with Holley an they told me If I change to carberator I would need a 12-841 fuel regulator because it would take the pressure coming out of the tank 87 iroc 350 an that I would have to change the 5/16 return line to 3/8 same as the feed. Can anybody give me some feedback on this. Thanks.

 

Part of what they said it true, If using the in tank pump with a carb you should have a return style regulator. Most carbs run around 6 lbs pressure.

Changing the return line size depends, TBI pumps run 9-12 lbs pressure while MPI pumps run as high as 60 lbs. I'm run'n a TBI pump in my GMC with the stock 1/4" return line and it works just fine, If your run'n a MPI pump I'd try the 5/16" return first before changing it out for it may work fine as well.

I plan on doing the same fuel system with the gen 1 swap in my GTA.


There are cheaper return style regulators on the market than the one they mentioned......

 

How would I change the 5/16 line to 3/8 on the pump they are telling me 3/8 for return to regulator 350 tpi to carb. 12-841 regulator Holley. not 5/16 Thanks Larry

 

Pressure doesn't matter to the size of the return line, volume does. If 5/16" was good enough to handle the flow of a stock pump with FI, it's good enough to handle it with a carb.

 

I have had no problems running the stock 5/16 return line in my 92. I'm using the original V6 fuel pump and a return-style regulator to feed the Holley on my 350. I have the Mallory 4309 regulator and run right around 7 psi to the carb.

 

Where do you mount your fp gauge? Summit's listing says it doesn't have a gauge port...kinda odd.

 

Sounds good to me I dont what they are talking about Holley an Mallory said the same to use 3/8 for return.Just one more question can I use Russuel hard line tube fittings to hook up my lines to use braided lines or could I use rubber hose an clamps an do they have to be fuel inj. hose because of the pressure coming out of the tank.Thanks Again Larry.

 

Pressure coming out of the pump won't be any higher than the regulator pressure. Braided lines and AN fittings are nice if they're in your budget.

 

So in other words I dont have to touch the pump in the tank at all . Just hook up a regulator an lines an a relay an thats all correct? If the car sits for a couple monts you wouldnt need nothing to prime it right? Thank You Larry.

 

Fuel should stay in the bowls. The electric pump should fill empty bowls in just a couple seconds if they are empty.

 

With any one of these that suits your choice of plumbing; http://www.summitracing.com/search?k...0fitting&dds=1

 

I mounted my gauge right at the carb. I just used a brass T plumbing fitting. The line comes into the 'bottom' of the T, one side of the 'crossbar' of the goes into the carb, the other goes into my gauge. The Mallory gauge I have also has 4 outlets, so I could have just screwed the gauge into one of those, but I wanted it right at the carb.