Automotive Forums .com - the leading automotive community online! Automotive Forums .com - the leading automotive community online!
Automotive Forums .com - the leading automotive community online! 
-
Latest | 0 Rplys
Go Back   Automotive Forums .com Car Chat > Panoz > GTRA / GTWS / GTS
Reply Show Printable Version Show Printable Version | Email this Page Email this Page | Subscription Subscribe to this Thread
 
Thread Tools
Old 07-11-2013, 01:34 PM   #16
Cobra4B
AF Enthusiast
Thread starter
 
Cobra4B's Avatar
 
Join Date: Jan 2008
Location: Virginia Beach, Virginia
Posts: 1,396
Thanks: 71
Thanked 63 Times in 58 Posts
Re: Where is your fuel pump mounted relative to the fuel level? Pump overheating.

Really appreciate the picture of the filter. Ordered a Summit racing 40 micron screen to replace the fram. Also got a non-liquid filled fuel pressure gauge.

What do you mean about "bottom fed pickups"? Our cell has the pickup that mounts to an anti-surge tank which is on the bottom of the cell. It pulls fuel off the very bottom of the inside of the box. Putting the pump level with the base of the cell like the GTS picture created a perfect siphon. When I took it apart to put the new pump in it took me a second to realize why the fuel wouldn't stop dumping out! Had to jump up and raise the line above the cell.



I fully understand what you're saying about the return being the way to go and I get why it works. If this setup fails to perform I'll go that route I saved the return line from when the car originally had fuel injection.

Oh... the unused "port" on the fuel cell is actually a dipstick for checking level. It's neat and much needed for a guy who changed a fuel pump in the hot paddock at VIR when he had run the car out of gas.
__________________
Brian B.
Panoz GTRA - LS1 swap in progress
#4 Z06 - NASA ST3/TT3
Cobra4B is offline   Reply With Quote
Old 07-12-2013, 09:17 AM   #17
Panoz60
AF Regular
 
Panoz60's Avatar
 
Join Date: Aug 2012
Location: Valrico, Florida
Posts: 144
Thanks: 38
Thanked 27 Times in 24 Posts
Re: Where is your fuel pump mounted relative to the fuel level? Pump overheating.

I probably used the wrong vernacular. By bottom feed, I meant like the one pictured below. This type of "outlet" is probably the most common.


What I believe is that with the type of cell you and I are running, the pump has to pull the fuel up and out of the cell no matter where the pump is mounted, so what difference would it make? I could be wrong.

This is a pic of the top of my cell. It is set-up for two independent pumps, I don't have the second one in use yet, nor do I have the vent connected, but it had a provision for the return line. I plan to plug and vent it and go racing. Eventually when I put the big motor in, I'll upgrade the lines to -8 and add a second pump to use both pick-ups (mine has a pick-up in both corners) For now, I can switch the hose from one side to another based on the track I run. (Sebring is predominantly R turns where Daytona has high G left turns) Anyway- Yours could be modified for a vent pretty easy with a -6 AN bulkhead fitting if you choose to go that route.


PS- If you talk to Pro-Systems, say "Hi" to Patrick James (Owner/Founder). We used to compete against each other here in Florida in A/S Mustangs when I first gave up roundy-round and started road racing. Patrick can drive!!. We got in some great carb arguments too. (He won most of them) Dude knows his stuff.
__________________
Mark W.
Panoz GTRA, Chassis #10
Panoz60 is offline   Reply With Quote
The Following User Says Thank You to Panoz60 For This Useful Post:
Cobra4B (07-12-2013)
Old 07-12-2013, 10:34 PM   #18
Cobra4B
AF Enthusiast
Thread starter
 
Cobra4B's Avatar
 
Join Date: Jan 2008
Location: Virginia Beach, Virginia
Posts: 1,396
Thanks: 71
Thanked 63 Times in 58 Posts
Re: Where is your fuel pump mounted relative to the fuel level? Pump overheating.

With the pump below the fuel level it creates a strong siphon so it doesn't have to pull the fuel up anymore. The siphon provides positive pressure at the inlet. Now if the pump is pushing more fuel than the siphon can provide that's one thing, but I have no idea if that's the case.

Regardless, the pump rad 100% cold on the dyno with back to back to back pulls a few times. It only heats up after 10 minutes at idle.
__________________
Brian B.
Panoz GTRA - LS1 swap in progress
#4 Z06 - NASA ST3/TT3
Cobra4B is offline   Reply With Quote
Old 12-21-2024, 11:16 AM   #19
MarkMc26
AF Newbie
 
Join Date: Jan 2019
Location: Winter Park, Florida
Posts: 21
Thanks: 2
Thanked 0 Times in 0 Posts
Re: Where is your fuel pump mounted relative to the fuel level? Pump overheating.

Digging this one up from the long, long dead...may be useful for anybody still running these cars.

From a conversation I had with John Leverett at Road Atlanta in April 2024, the EFI fuel pumps were all mounted "up high" so they would be easier to change if they failed (quick repair turnaround on the school cars, compared to putting pumps inside the cells). But, the higher location forced the pumps to lift fuel a foot and a half from the bottom of the cells (which they hate), so that decreased pump life right off the bat. "If" they fail turned into "when" they fail and I guess the solution created the problem. I'm pretty sure the carbureted GTS pumps were mounted near the bottom of the cells, on the front/passenger side of the cell, so pump height relative to pickup shouldn't be an issue for them.

Anyway, I've been chasing low pressure/assumed vapor lock issues that understandably started when I built the single exhaust to run down the passenger side (double the heat in the same area), with the muffler currently just a few inches from the single, dead-headed EFI fuel line (vapor lock was horrendous with the return-style fuel system and previous, wildly oversized Bosch pump, getting heated up in both directions). The pump was getting "pretty warm" but I wouldn't call it "hot." As an easy start, a bunch of heat wrap and shielding around the fuel line and underhood hose slightly reduced it but didn't cure it. I moved the Summit-sourced Walbro pump (no sketchy Amazon or eBay sellers with faulty knockoffs) from the usual "up high" location to down on the chassis rail, level with the bottom of the cell, to get help from the siphon after it initially primed (11" square Holley Hydramat in there for the pickup works great). It greatly reduced/delayed the low pressure problem, although it did slightly crop up once in a 30 minute session. Same weekend, switching from genpop 93 octane pump gas to $15/gallon 98 octane Sunoco 260 GTX with its theoretically higher evaporation/vaporization/boiling temperature got rid of the fuel pressure issues over the course of 30 track minutes in anger. So, the next fuel system project will be to run the dead-head supply line down the driver's side, where there is no exhaust. I'll still keep the pump low and outside the cell for ease of trackside maintenance, as long as I don't start burning them up.

Mark
__________________
PGTWC-13 #26, NASA TT3
MarkMc26 is offline   Reply With Quote
 
Reply

POST REPLY TO THIS THREAD

Go Back   Automotive Forums .com Car Chat > Panoz > GTRA / GTWS / GTS

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 08:40 AM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
 
 
no new posts