Hey guys. Long time lurker, first time poster.

I put a Vortec 350 in the 1986 Firebird that my son and I are working on for his first car. The car was originally a carb 305. The new engine will be running a Holley 650 and I'd prefer to run an in tank fuel pump but I'm not sure what sender I need. Also not sure if the tank needs to be swapped for a FI tank?

 

GM used to sell a ZZ4 kit that upgraded the 305 to a 350. The kit is no longer available, but these instructions sound similar to what your want. GM part numbers are included.

https://www.thirdgen.org/forums/engi...tructions.html

 

Aeromotive has a drop in unit. It works awesome in have the full stealth system in my TA. The bigger pump will supply at least 600hp. It works w a stock fuel gauge. You'll need to wire in a 30 amp solenoid and use 10ga wire.

IN-TANK FUEL PUMP & HANGER, 82-92 CAMARO

Part Number: 18071

 

https://aeromotiveinc.com/products/8...47675268170028

I've got the bigger 340 lph pump going in my car eventually. It's a very nice piece if you don't mind spending the $$$.

Probably pretty overkill for a carb application though.

 

It's probably overkill for the OPs build at this point. That said, dropping and swapping the tank is so miserable it's probably best to future proof it. When I put mine in 2 yrs ago I had a 430hp setup. Now a blower is going on and I'm really happy I have the fuel supply for it. I'd rather do an engine or trans over dropping that fuel tank again.

 

I'd buy the cheapest auto-parts store sending unit and pump (assy) that I could get, slap it in there. Then I'd devise a sufficient regulator, and I think it'd run great.

 

This brings up an interesting point and one that I've been investigating so I have something in place when the new high pressure pump replaces the old Holley Blue.
On the Holley side of things, this is the only regulator I've found that's suitable.

https://www.holley.com/products/fuel...s/parts/12-841

The criteria is to go from 45+ PSI pump output to a carburetor friendly 5 PSI.
There are AN and NPT versions available. Return style is mandatory in my case.
If there's anything else (Aeromotive perhaps or Walbro) I'm all ears.

 

There is. I made a return style FPR out of the top of a GM truck TBI unit (the FPR part).

You're not "reducing from 45 PSI". The pump doesn't make pressure, pressure is resistance to flow, so "45 PSI" really comes from the regulator found on many MPFI engines that is designed and calibrated (by the spring inside, + the surface area of the valve) to provide 45 PSI's worth of resistance to the pump's flow. In the case of a carb application, you already have an electric fuel pump that moves fuel...way more than you need. To make that work, all you're doing, is providing ~5 PSI worth of resistance to flow in the return loop (which ANY return style FPR will do w/the right spring). Used on a SBC swapped Jeep Wrangler that was originally a 4 cyl MPFI engine, my home-made TBI FPR cost me about $0.00 and worked great, feeding a typical Q-Jet carb.

 

Ok.

 

Whatever you do, make sure it supports both expected and future power levels with EFI. Having to redo your fuel system because you got a good deal on a Sniper or FAST would be quite the bummer.

 

Another option, you can just hang a pusher pump (like a holley blue) outside the tank and run it to the regulator. My set-up was like that for over a decade before I finally decided to drop the tank and remove the in-tank pump and basically fabricated a carbureted sending unit (which are like hen's teeth to find).

 

Thanks all for the input. It's greatly appreciated.

I ended up plumbing an inline pump near the tank and a regulator near the carb. I'll address adding a sending unit with more PSI if/when we decide to add FI.

 

What are you using for a pump and regulator?

 

Using a Holley Mighty mite pump and Holly return regulator.

 

If I didn't already have this high zoot pump from (now extinct) SX Performance that little Holley looks to be a much better replacement than this noisy Blue I currently have.
I find it interesting in that...
...they are all rated as such. Even though I understand exactly what the quoted text is trying to say.

 

Yep. B/c the pumps have a limit to the resistance to flow, that they are able to over come. That is the rating that you're seeing -a maximum..."up to". The regulator is what gets you to the pressure that you want or need for your combo. Put that pump in a bucket of liquid, apply power to it...how much pressure is it making?

 

While there is a free flow value assigned to many pumps (specifically electric fuel pumps for an automotive application) that number has little value in a working system.
All pumps are rated at a given volume for a given PSI. I think we can agree on that? To refine the suitability for any pump, you would need to know the pumps pressure curve. GPH vs PSI vs voltage, etc. Not all are created equally.
But my topic of conversation, and the OP's original question notwithstanding, regards regulators.
They too are not all created equally, and according to the Holley tech (for what that's worth) I spoke with, some can handle a large transition (60 PSI to 5 PSI as an example) and some can't.
My post with the (Holley)12-841 vs the 12-803 is a reference to that. Can the 12-803 be modified to work with a large output pump? I suppose anything is modifiable although it was suggested to me by said Holley tech that no, it isn't.
I'd really like to see the modification you mentioned, what was involved and what the final product looks like as installed. I'm intrigued.

 

EXACTLY. And that was my original point.


I love that the Holley tech said no...to a part that is sold to go on a car, where.....you're modifying the whole thing! I get his position though....he can't assure you of anything if he greenlights mods.


Let me look and see if I can find pics of that thing. It was a LOOOONG time ago....

 

Yes, the Holley tech certainly has to have a bias. That bias probably aimed at selling parts. That said, even though I have more resources than the average garage hotrodder (thanks to where I make my daily wage) it's often easier to buy than build. I'll venture a guess and say that's where this regulator drops in.
Your particular bit of resourcefulness isn't unfamiliar to me though. I've often had to put parts together that otherwise wouldn't be put together. I suppose that's a reference to your...

 

Yep.

I can't find that pic. And I figured out why: I hosted it back in ~'07 on Photophucket, so that pic...and a ton of my other pics, got....phucked. Picks are gone. Best I can offer is this description and a stock photo that I modified, from a thread where I described it....

"I used a TBI FPR/housing. I chopped off the injector "covers"/hold-downs, pipe thread tapped the in/out ports (in/out/return), reduced the spring pressure to get it down to 5-7 PSI from the 12ish it was factory set to.....and installed it in a convenient place under the hood using a "T" between the tank/pump, and the regulator for my carb feed. Worked flawlessly for years until and beyond when the vehicle was sold"