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Opeler
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2,995 Posts
Are calibration parts (jets, etc.) the same between original Weber and Czech / China knock-on carburetor?

:thinking: Holley fuel pressure regulator is not reducing pressure?
Maybe you can return pressure regulator and /or fuel pump?
https://www.racetep.com/manufacturer/carbs-and-injection/weber/electric-fuel-pumps.html
Holley Fuel Pumps with Regulator: This is a very common combination and it has alot of problems. The pump puts out too much pressure so you have to buy a regulator for it. The Regulator is just a restrictor that inhibits flow. This causes a huge loss of Volume and overloads the pump causing alot of noise and premature failure. This results in the float bowl going low or empty under hard acceleration and causes cornering problems.

Gordo, This is what I ordered last week off Amazon https://www.amazon.com/gp/product/B07BBDSZP1/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
This is what was recomended and fixed my problems, 4 gal/min. HTH. Jarrell
That's the one I installed last Fall and reinstalled today.
Ask Racetep if fuel pump is above 4 psi, buyer can return? Does not look like Carter P90091.
https://www.racetep.com/manufacturer/carbs-and-injection/weber/electric-fuel-pumps/lower-cost-singe-carb-pump.html
Lower Cost Weber Carb Fuel Pump For Applications Below 150 HP. Single Or Dual Carbs Street Applications
NO REGULATOR OR RETURN LINE NEEDED OR USED.
Lower Cost Single Carb Pump or Dual Carbs below 150 HP
SKU: efp_0002 $79.00

Will not fit current location near GT Gas Tank.
https://www.racetep.com/manufacturer/carbs-and-injection/weber/electric-fuel-pumps/carter-4070-fuel-pump-with-mounting-bracket-kit.html
Carter High Volume Low Pressure Fuel Pump With Mounting Bracket Kit
No Pressure Regulator Needed. No Return Line Needed.
This is the pump to use for Dual, Triple, or Quad IDF/IDA Webers or any Track car with a 2 Barrel or more Weber carb.
SKU: efp_0001 $89.95
 

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Just Some Dude in Jersey
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14,286 Posts
Discussion Starter #385

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Opeler
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1,160 Posts
I used to use star tron. Had to have my motorcycle carbs rebuilt twice. All the motorcycle shops around me use Liquid Performance Ethanol Equalizer. Best stuff out there. Expensive but it is the best.

Karl
 

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Just Some Dude in Jersey
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14,286 Posts
Discussion Starter #388
:veryhappy

I've reconnected the fuel lines to the reg and the Edelbrock pump and I'm slowly tuning my timing and carb with test rides. Today I will probably stop by Horror Freight and grab one of those cheap gauges that FT suggested. I've got to get a trustworthy handle on how many psi that reg is actually allowing through. I unscrewed it a lot to get to the 2psi I had set it to with the gauge, but since I can't trust the gauge, due to both new pumps reading way higher than they should, my setting could be anywhere. I may have it set to over-regulate and I might only be getting 1psi for all I know.

The car runs pretty good, but I'm a little stumbly when accelerating. I want to make sure that that isn't caused by fuel starvation. Yeah, I could just run a straight fuel line to the carb and bypass the reg, but since you guys have me all paranoid for the first time in 40 years of electric fuel pumps in my GT's, I now have to play a merry dance with multiple gauges, multiple regs, and multiple fuel pumps until I feel I can trust my fuel delivery system.
 

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Über Genius
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8,934 Posts
Doesn't your Dakota digital whatchamajiggit have an input for fuel pressure. All you need is a sensor for it, right?
 

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Senior Contributor
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4,971 Posts
Doesn't your Dakota digital whatchamajiggit have an input for fuel pressure. All you need is a sensor for it, right?
I have never been able to find a sensor that is good for gasoline. They all say specifically "not for use with fuel". I have the PLX multigauge and I thought it would be great to bring in fuel pressure too but so far it is a no go.
 

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Registered
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690 Posts
:veryhappy

I've reconnected the fuel lines to the reg and the Edelbrock pump and I'm slowly tuning my timing and carb with test rides. Today I will probably stop by Horror Freight and grab one of those cheap gauges that FT suggested. I've got to get a trustworthy handle on how many psi that reg is actually allowing through. I unscrewed it a lot to get to the 2psi I had set it to with the gauge, but since I can't trust the gauge, due to both new pumps reading way higher than they should, my setting could be anywhere. I may have it set to over-regulate and I might only be getting 1psi for all I know.

The car runs pretty good, but I'm a little stumbly when accelerating. I want to make sure that that isn't caused by fuel starvation. Yeah, I could just run a straight fuel line to the carb and bypass the reg, but since you guys have me all paranoid for the first time in 40 years of electric fuel pumps in my GT's, I now have to play a merry dance with multiple gauges, multiple regs, and multiple fuel pumps until I feel I can trust my fuel delivery system.
If you have a fuel starvation problem, it's because of a lack of volume, not pressure. A carb doesn't need fuel pressure to squirt fuel in the engine, the air/fuel mix is sucked in by the pressure difference in the venturi. Stumbling at acceleration is usually caused by too small idle/transition jets or an acceleration pump that doesn't work as it should.
 

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Member
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1,183 Posts
If you have a fuel starvation problem, it's because of a lack of volume, not pressure. A carb doesn't need fuel pressure to squirt fuel in the engine, the air/fuel mix is sucked in by the pressure difference in the venturi. Stumbling at acceleration is usually caused by too small idle/transition jets or an acceleration pump that doesn't work as it should.
Or incorrect timing. Has the timing ever been verified or is it still being set by ear?
 
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4,231 Posts
:veryhappy

The car runs pretty good, but I'm a little stumbly when accelerating. I want to make sure that that isn't caused by fuel starvation. Yeah, I could just run a straight fuel line to the carb and bypass the reg, but since you guys have me all paranoid for the first time in 40 years of electric fuel pumps in my GT's, I now have to play a merry dance with multiple gauges, multiple regs, and multiple fuel pumps until I feel I can trust my fuel delivery system.
Start right now,next Carlisle comming soon.Not eat ice cream or sitting in the Garden:lmao:

A 2.5 with SSD and electric fuel pump:thinking:
You need a next gauge cluster:haha:

https://www.flickr.com/photos/rohanpatelphotography/27434627839
 

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Just Some Dude in Jersey
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14,286 Posts
Discussion Starter #395
The Frozen Dude suggested I get this cheapie gauge kit from Horror Freight to get a second opinion on my fuel pressure:

https://www.harborfreight.com/Fuel-Pump-and-Vacuum-Tester-62637.html?fbclid=IwAR0HJyFEWPQF-QSCCqiaVkoJs2KtF_I_-dYMLLXmzEjvyxFmzg5Joygc5ng

I just stopped by Horror Freight, couldn't find the one he linked to, and bought the gauge below instead. It's not the same as what JJ found, but it is a combo vac and pressure gauge. But it says it's for Nitrous and says nothing about testing liquid or fuel pressure. However, the gauge JJ found is also a pressure/vac gauge and it actually says fuel pressure, but it also says it can sense vacuum which is gaseous. Both kits come with the same assortment of fittings and hoses. I'm only likely to use this gauge once and I don't care if it gets destroyed by the fuel getting into it. Do you guys think it will get the job done?

https://www.harborfreight.com/2-inch-led-lit-boost-vacuum-gauge-98478.html?_br_psugg_q=nitrous
 

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Just Some Dude in Jersey
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14,286 Posts
Discussion Starter #397
Or incorrect timing. Has the timing ever been verified or is it still being set by ear?
Well, what is "correct" timing? PJ says that his engine runs best at 10* of advance, Charlie says his Kadett likes 8*. In my opinion, correct timing is when the engine starts, runs, and performs best. If you're dead set that 15* of advance is correct, but your engine runs like junk, and you keep doing stuff to your engine to try to make it runs great at 15*, but you can't do it, but when you set it to 12* the angels break through the clouds and blow their trumpets with happiness, then 12* is best. I put 225K on my previous GT and it ran great when I sold it and it's stilling running 15 years later. I have no idea what the timing was at various points during the 18 years I drove it every day. I tuned it by ear and seat of the pants for best overall performance.

Now as a reference point to begin timing an engine, yeah I could see the value of knowing what the timing was before I did something that changed the timing. I'll start with that timing mark, but if the engine doesn't perform good overall, I'm going to play with the timing a degree or so fore and aft to find the sweet spot. My engine is modified: Bigger pistons and valves, a RallyBob customized locked plate dizzy with different mech advance springs and altered/limited range, no vac advance, a side draft which shoots gas in a little quicker, etc. All these things make my engine a little different that a stock 2.4 with FI.

Apparently I know what I'm doing with my ear and my azz, otherwise my previous GT with a 2.0 and a Combo cam wouldn't have lasted so long and ran so good.

:veryhappy
 

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Just Some Dude in Jersey
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14,286 Posts
Discussion Starter #398

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Member
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Well, what is "correct" timing? PJ says that his engine runs best at 10* of advance, Charlie says his Kadett likes 8*. In my opinion, correct timing is when the engine starts, runs, and performs best. If you're dead set that 15* of advance is correct, but your engine runs like junk, and you keep doing stuff to your engine to try to make it runs great at 15*, but you can't do it, but when you set it to 12* the angels break through the clouds and blow their trumpets with happiness, then 12* is best. I put 225K on my previous GT and it ran great when I sold it and it's stilling running 15 years later. I have no idea what the timing was at various points during the 18 years I drove it every day. I tuned it by ear and seat of the pants for best overall performance.

Now as a reference point to begin timing an engine, yeah I could see the value of knowing what the timing was before I did something that changed the timing. I'll start with that timing mark, but if the engine doesn't perform good overall, I'm going to play with the timing a degree or so fore and aft to find the sweet spot. My engine is modified: Bigger pistons and valves, a RallyBob customized locked plate dizzy with different mech advance springs and altered/limited range, no vac advance, a side draft which shoots gas in a little quicker, etc. All these things make my engine a little different that a stock 2.4 with FI.

Apparently I know what I'm doing with my ear and my azz, otherwise my previous GT with a 2.0 and a Combo cam wouldn't have lasted so long and ran so good.

:veryhappy
I’m not suggesting that there is a magical one size fits all, but rather that it is important to know where the timing is currently set and how that compares with what it was when the engine ran well. You can never have too much data. My 2.0 with dual DCOEs runs best with 8 degrees BTC. If it’s performance suffers sometime in the future, that would be one of the things I would verify in the troubleshooting process.
 
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