The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Engine Starves for Fuel When I Hit Second Gear

Marv D · 10-14-2009, 07:31 PM

The one question no one has asked yet,, what fuel pressure gauge are you using that says it's only 2psi? The one common denominator here and I didn't see anything saying the gauge was verified. I will say this,, if it's an autometer with an isolator so you can read fuel pressure inside the cabin,, your kidding yourself if you think it is anywhere near accurate. But typically those show low VERY low when cold, and pressure increases as underhood temps rise.

OK, I'm going back to you have a CARB problem, not a fuel delivery problem. Without getting into a peeing match here, I will promise you that 2psi of fuel pressure in 5/16" will keep enough fuel in the float bowls to get you through 2nd gear. And backing up,,, I will tell you for absolute fact that you can run to nearly 1/2 track under WFO throttle with a 600HP small block before you run out of gas with the fuel pumps OFF. The BG float bowls are not any smaller than a Holley 4150 so at very WORST I'd say your at the 1/8th in high gear before it starts starving. Also think about this. A 5/16" line with 2psi of pressure IS fuel delivery. So your going to make it past 1/2 track pulling in high gear before it drains the float bowls. So,, running out of fuel pressure...... I'm not going to buy it.

WHY you have low fuel pressure?? I don't know and I wouldn't be concerned at this point till you have your carb issue straightened out.

Try this,,,, borrow a KNOWN working Holley and slap it on the truck for a few test passes. See if it's the CARB, or fuel delivery. I bet a dollar to a donut that although you do indeed have something showing low fuel pressure, that is NOT why it's falling on it's face in 2nd gear.

I hate to try and compare apples and orangutans, but I'm right in line with 383RAM and here is a FACT. I'm sure DJ and some of the other quicker guys that data log can verify the same scenario. My smallblock Nova dyno'd 797HP, runs 9.teens at 147 and I use a single Mallory 250GPH pump with an-8 fuel line. When I launch I drop to 1.5 to 2psi of fuel pressure. It recovers to 3+psi 2.5 seconds into the pass. It is not until 8 seconds that the fuel PSI ever recovers to 5.5psi or above. And I am NOT starving for fuel anywhere along the pass.

So... I again say. BORROW A GOOD WORKING HOLLEY CARB and watch your 2nd gear problem magically disappear.

10-14-2009, 07:31 PM	#24
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	Re: Engine Starves for Fuel When I Hit Second Gear The one question no one has asked yet,, what fuel pressure gauge are you using that says it's only 2psi? The one common denominator here and I didn't see anything saying the gauge was verified. I will say this,, if it's an autometer with an isolator so you can read fuel pressure inside the cabin,, your kidding yourself if you think it is anywhere near accurate. But typically those show low VERY low when cold, and pressure increases as underhood temps rise. OK, I'm going back to you have a CARB problem, not a fuel delivery problem. Without getting into a peeing match here, I will promise you that 2psi of fuel pressure in 5/16" will keep enough fuel in the float bowls to get you through 2nd gear. And backing up,,, I will tell you for absolute fact that you can run to nearly 1/2 track under WFO throttle with a 600HP small block before you run out of gas with the fuel pumps OFF. The BG float bowls are not any smaller than a Holley 4150 so at very WORST I'd say your at the 1/8th in high gear before it starts starving. Also think about this. A 5/16" line with 2psi of pressure IS fuel delivery. So your going to make it past 1/2 track pulling in high gear before it drains the float bowls. So,, running out of fuel pressure...... I'm not going to buy it. WHY you have low fuel pressure?? I don't know and I wouldn't be concerned at this point till you have your carb issue straightened out. Try this,,,, borrow a KNOWN working Holley and slap it on the truck for a few test passes. See if it's the CARB, or fuel delivery. I bet a dollar to a donut that although you do indeed have something showing low fuel pressure, that is NOT why it's falling on it's face in 2nd gear. I hate to try and compare apples and orangutans, but I'm right in line with 383RAM and here is a FACT. I'm sure DJ and some of the other quicker guys that data log can verify the same scenario. My smallblock Nova dyno'd 797HP, runs 9.teens at 147 and I use a single Mallory 250GPH pump with an-8 fuel line. When I launch I drop to 1.5 to 2psi of fuel pressure. It recovers to 3+psi 2.5 seconds into the pass. It is not until 8 seconds that the fuel PSI ever recovers to 5.5psi or above. And I am NOT starving for fuel anywhere along the pass. So... I again say. BORROW A GOOD WORKING HOLLEY CARB and watch your 2nd gear problem magically disappear. __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.