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Re: The POS is a goer once more..... But....
Posted: Mon Dec 13, 2010 8:43 pm
by ToRy 70
We're all mad here.
Just don't expect a cure-all with FI, I had plenty of fuel pressure issues that I don't want to start another argument about here.
Re: The POS is a goer once more..... But....
Posted: Mon Dec 13, 2010 10:16 pm
by Fiatdude
OK 2 things
1. you're running a freaking side draft suck ass carb -- put a holley (AJ's 2 barrel 500 cfm is light years more advanced than that carb) or go FI -- If you insist on running that POS you've got to have a boost referenced regulator or that thing will continue to lean out on boost. (you have to increase the fuel pressure to get enuff fuel into the bowl at any boost pressure) CarCraft in Riverside CA has them (they advertise on here) and they work good. IF you insist on running that carb and thinking about making any HP, be prepared to run that thing without almost no jets in it to get enuff fuel thru it -- goes for the float bowl too.
2. I've ran thru a bunch of Blues and Black Holleys -- they are overheating because you aren't running enuff fuel thru them to keep them cool -- figure out a bypass that lets some fuel circulate thru them
Re: The POS is a goer once more..... But....
Posted: Tue Dec 14, 2010 5:02 am
by Humpty
Scored a Carter Black today.... Gonna fit that up tomorrow and give it a shot..... I have a malpassi rising rate FPR on there now, but have had some problems getting the pressure right..... Gotta stick with the Weber too.... For now at least.... I understand your comments about the Holley Carb option, but really not an option for me.... It would be next to impossible to fit it under the decklid I reckon.... At least with it placed where the weber currently is.... If I moved it further around the shroud next to the firewall, the intake tract would be stupid long, and would possibly cause more issues.... Think I will go EFI before I go Holley.
Re: The POS is a goer once more..... But....
Posted: Tue Dec 14, 2010 10:48 pm
by Fiatdude
Humpty wrote:Scored a Carter Black today....
If I moved it further around the shroud next to the firewall, the intake tract would be stupid long, and would possibly cause more issues.... Think I will go EFI before I go Holley.
TOOO much pump -- been there done that -- will burn itself down -- -- -- Intake can be as long as you want -- might lose a little instantaneous throttle response but .. Killer top end -- LOL can you say tunnel ram
Re: The POS is a goer once more..... But....
Posted: Tue Dec 14, 2010 11:04 pm
by Humpty
Fiatdude wrote:
TOOO much pump -- been there done that -- will burn itself down -- -- --
Bloody hell..... I just picked it up!!!!..... Special freakin order!!!!..... Can't take it back!!!!!!!..... Was told it'll be fine..... FARKIT!!!
I've been asking these questions for months and getting different answers everytime.... Tried every combo known to man.... Can't get anything to work....
I hope someone else will learn from all this....
Re: The POS is a goer once more..... But....
Posted: Thu Dec 16, 2010 9:48 pm
by MarioVelotta
Could you do a quick drawing of your current fuel system. In paint or freehand on paper, I don't really care. Just want to see a pic.
Re: The POS is a goer once more..... But....
Posted: Thu Dec 16, 2010 11:34 pm
by Humpty
MarioVelotta wrote:Could you do a quick drawing of your current fuel system. In paint or freehand on paper, I don't really care. Just want to see a pic.

Re: The POS is a goer once more..... But....
Posted: Thu Dec 16, 2010 11:47 pm
by MarioVelotta
Can you put a pressure test on your return line? With such small pump pressure I wonder if the return it fighting tank pressure, just shooting on the dark. Also you say it goes crazy lean. Could it be possibly going rich instead giving a false lean from all the extra oxygen? Have you pulled plugs after it dies to see if there is just a ton of fuel in a cylinder unburned... Plugs good not fouled up?
Just thinking out loud

Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 3:49 am
by Humpty
MarioVelotta wrote:Can you put a pressure test on your return line? With such small pump pressure I wonder if the return it fighting tank pressure, just shooting on the dark. Also you say it goes crazy lean. Could it be possibly going rich instead giving a false lean from all the extra oxygen? Have you pulled plugs after it dies to see if there is just a ton of fuel in a cylinder unburned... Plugs good not fouled up?
Just thinking out loud

What????.... No comments on how cool my
"quick'n'dirty" diagram is?
But yes.... I believe you are on the right track.... I have not tested the return line for pressure..... But the local 'boosted knowledge bank' suggest the same thing.... Hence the current upgrade project of changing out the 3/8" lines for 1/2".... I have not pulled the plugs, but feel the plugs to be ok.... The car starts and runs sweetly after the 'crazy lean' experience... If this issue continues after the upgrade, I'll be sure to check the plugs....
Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 6:46 am
by Hotrodvw
That's a damn fine diagram if I do say so my damn self.

Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 7:06 am
by turbobaja
Very nice diagram Humpty! Is the Malpassi returning reg the only one in your system now?
I can't imagine the return line needing to be any larger than 3/8". I'd be curious how your plugs look too.
Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 7:13 am
by Hotrodvw
The return line needs to be full flow, same size as the supply is ideal, or next size down. Are you using the stock line for a return, or??
Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 8:16 am
by Humpty
Cheers fellas..... Good to see my 20 years as a graphic designer haven't gone to waste!!!!
Hotrodvw wrote:The return line needs to be full flow, same size as the supply is ideal, or next size down. Are you using the stock line for a return, or??
As for the lines.... As of yesterday, all lines are 1/2".... They were 3/8" before that.... And the Malpassi is the only reg being used....
Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 8:43 am
by Hotrodvw
Good gravy son! 1/2"??! You shouldn't have any flow problems for quite a while.
Re: The POS is a goer once more..... But....
Posted: Fri Dec 17, 2010 9:18 am
by Humpty
Hotrodvw wrote:Good gravy son! 1/2"??! You shouldn't have any flow problems for quite a while.
Nothing beats over kill!!!!
