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Modified 150 HP Fuel Question
Posted by: eimis ()
Date: April 11, 2018 07:23PM

Hey guys,

I recently got everything back together for my 1964 Spyder.

List of items added or modified:

External wastegate set to 10 PSI
Hybrid turbo from a 150/180 HP
Pertronix ignition
Holley fuel pressure regulator
Holley 350 CFM two barrel modified by lowbugget.com for turbo applications

When I get to about 3000 RPM, the engine sputters and doesn't want to keep going or build boost. I'm thinking it's a fuel pressure problem as no matter how I adjust the air/fuel screws or the adjust-a-jet on the carb's metering block, it still wants to stumble. Does anyone have any pointers of where to start with my problem solving?

Thanks

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Re: Modified 150 HP Fuel Question
Posted by: MattNall ()
Date: April 11, 2018 07:28PM

Got a gauge on the system... Holly's want 5 psi IIRC





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: Modified 150 HP Fuel Question
Posted by: eimis ()
Date: April 11, 2018 07:30PM

MattNall Wrote:
-------------------------------------------------------
> Got a gauge on the system... Holly's want 5 psi
> IIRC

The regulator I have tops out at 4 PSI. Do you reckon that's part of the problem?

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Re: Modified 150 HP Fuel Question
Posted by: MattNall ()
Date: April 11, 2018 07:43PM

Possibly.... you need a gauge to see...

Buy one of these and use your DVM! $12

[www.ebay.com]





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: Modified 150 HP Fuel Question
Posted by: thewolfe ()
Date: April 12, 2018 08:16AM

Could also be an issue with what low bugget did. I bought a modified holley from them once with an obvious fuel problem. It was dumping gas into my engine, off the scale rich diluting the oil and the guy swore up and down there was something wrong with my motor yet it ran perfectly before the carb swap. This was after the wrong air filter was sent not once but twice. I finally sent the thing back to them and they fixed the fuel problem but the dude still would not admit that him or his shop had made a mistake. I don't deal well with people like that and won't ever buy anything from or recommend them to anyone after that experience.

Nate Wolfe
Portland OR
65 Corsa 180

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Re: Modified 150 HP Fuel Question
Posted by: eimis ()
Date: April 12, 2018 12:14PM

thewolfe Wrote:
-------------------------------------------------------
> Could also be an issue with what low bugget did. I
> bought a modified holley from them once with an
> obvious fuel problem. It was dumping gas into my
> engine, off the scale rich diluting the oil and
> the guy swore up and down there was something
> wrong with my motor yet it ran perfectly before
> the carb swap. This was after the wrong air filter
> was sent not once but twice. I finally sent the
> thing back to them and they fixed the fuel problem
> but the dude still would not admit that him or his
> shop had made a mistake. I don't deal well with
> people like that and won't ever buy anything from
> or recommend them to anyone after that experience.


What problem were you having? I thought it was my pressure retard since the diaphragm was ruptured on it. But after I replaced it I still get the bogging about 3000 RPM.

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Re: Modified 150 HP Fuel Question
Posted by: thewolfe ()
Date: April 12, 2018 12:29PM

Different problem. I couldn't even drive my car. It would idle fine but as soon as I gave it any gas it would literally dump a geyser of fuel down the throat and cause the engine to die from being extremely over rich. Do you have a wideband afr gauge? That will give you good info on what might be going on. If not, I would recommend installing one. Makes tuning non stock carbs much much easier.

Nate Wolfe
Portland OR
65 Corsa 180

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Re: Modified 150 HP Fuel Question
Posted by: eimis ()
Date: April 12, 2018 01:48PM

thewolfe Wrote:
-------------------------------------------------------
> Different problem. I couldn't even drive my car.
> It would idle fine but as soon as I gave it any
> gas it would literally dump a geyser of fuel down
> the throat and cause the engine to die from being
> extremely over rich. Do you have a wideband afr
> gauge? That will give you good info on what might
> be going on. If not, I would recommend installing
> one. Makes tuning non stock carbs much much
> easier.

No, I don't have any gauges other than the tach right now. I plan on installing some new gauges that work.

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Re: Modified 150 HP Fuel Question
Posted by: roger65180 ()
Date: April 12, 2018 04:38PM

I agree with Nate an air fuel gauge makes tuning a carb on turbo cars much easy'er also put a gauge on the fuel line those fuel regulators are in my opinion junk . I would remove the regulator and test your pump pressure a stock pump should be 3 to 5 lbs

Roger R
Madison Wi
62 ct pg turbo
65intercooled 180 4sp,autocrosser
62 Rampy

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Re: Modified 150 HP Fuel Question
Posted by: eimis ()
Date: April 12, 2018 04:55PM

I think I figured out 90% of my problem, at some point in time my timing was set to almost 0 degrees. Found this out when I put my timing light on the car today. Put it back to 24 degrees and it seems to have smoother out the roughness.

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