'63 Nova rev problem

I got this car in pieces and spent a year restoring it. It originally was a 6 cylinder with a 3 speed on the column. I put a 350HP 350 with a TH350 in it.
I removed the 5/16" sending unit and installed a new 3/8" and ran new 3/8" hard line all of the way to the Edelbrock mechanical fuel pump. I covered all of the fuel lines where they go next to the headers, so I don't think there is any possibility of vapor lock.

When the temp. is over about 70 deg. F, it revs fine in 1st gear, but seems to run out of fuel in 2nd gears and stops pulling which continues into 3rd gear. If it is cold out, this car runs fine through all 3 gears...pulling HARD all the way to 5500 RPM.

The engine is a .030 1971 350 with 882 heads 1.94 intake, 1.50 exhaust 76cc chamber. Flat-top TRW pistons. Comp cams XE268H cam. Edelbrock Performer RPM, 750 Edelbrock carb. Shortie headers with 2 1/2" exhaust. 34 deg. of total timing...MSD 6A ignition(Tried different timing)

I have had the carb apart several times and adjusted the floats, checked filters, just about everything I can think of. I haven't tried to re-jet yet because the spark plug reading looks good.

Anybody have any ideas?

I'd drain the tank and flush it out and blow air through the line to the fuel pump.
Before i did that I'd chuck the filter in the carb if it's still there.

The tank was flushed when I restored the car and the filter is clean on the carb and the main filter is new. (600 miles on it) I also cut the filter open when I changed it a couple of weeks ago just to see if there was anything in it. It was sparkling clean. I have NEVER had even a HINT of any kind of fuel hesitation or fuel starvation on normal driving. It is only above 70 degrees doing a simulated quarter mile run on the way home from work. I have tried just about everything.

Do you have a vent on the tank, or a vented fuel cap??? Might want to check to make sure the tank can breathe.....

I'd still chuck the filter in the carb because as far as I'm concerned they are too restrictive. Other than that the only other thing I could think of would be the fuel pump.

Wow...it is a non vented cap! I will do a 1/4 run tomorrow without the cap. (I live WAY out in the country in Oklahoma). I will also try to gets some pics of my setup.

fuel pump push rod binding up when it's hot?

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Originally Posted by firebird77clone

fuel pump push rod binding up when it's hot?

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i think it run off the cam no push rod i would bet it is heat

edlebrock carbs are quick to empty out of gas .. my V6 pinto would do what you speak of till i replumbed from the tank to the carb .. and be sure you have at least 5 psi fuel pressure but not more than 7

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Originally Posted by HOSS429

edlebrock carbs are quick to empty out of gas .. my V6 pinto would do what you speak of till i replumbed from the tank to the carb .. and be sure you have at least 5 psi fuel pressure but not more than 7

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While Holleys can stand a little more, Edelbrocks should be run at 5 psi max.

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Originally Posted by techinspector1

While Holleys can stand a little more, Edelbrocks should be run at 5 psi max.

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i stand corrected .. even my pinto regulator is set at 4.5 lbs .:)

Well, as embarassing as it is, I think I found the problem. The flex line that goes between the fuel sending unit and the hardline has a kink in it. I put a picture of it in my profile. Now why it would do only when it was hot makes no sense. Since it is going to be in the 80's today, I will see if that is it and put a result in this thread.

Great advise...thanks!

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Originally Posted by jbright300

Well, as embarassing as it is, I think I found the problem. The flex line that goes between the fuel sending unit and the hardline has a kink in it. I put a picture of it in my profile. Now why it would do only when it was hot makes no sense. Since it is going to be in the 80's today, I will see if that is it and put a result in this thread.

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It would do that as it gets hot due to the fact that liquids generally expand as the heat rises.

Well, to my dissapointment, that didn't fix it. I replaced the hose at the tank with high pressure line and did 2 runs. One with the gas cap on and one with it off.....no change. It still acts like it is running out of fuel in 2nd gear. I am going to post some more pics of the fuel pump setup in my personal photos.

They should be here:

http://www.clubhotrod.com/photopost/...at=500&thumb=1

If you give me an email address, I will send them to you.

Right to the left of the kink in your fuel line the line is too close to the exhaust. I would slip some heat wrap over the fuel line in that area.

Okay, now I am confused. I started out this morning by removing the banjo fitting on the inlet of the Edelbrock carburetor to look inside to make sure there was nothing in there causing a restriction. The ID of the fitting is 5/16"! WTF? I spent a lot of time making sure the was 3/8" from the tank to the fuel pump(The 6 cyl Nova has 5/16" line and sending unit). Is this the right fitting for a 750 Edelbrock Carb?

Sounds like it is vapor locking. To much heat under the hood. Exhaust to close to the fuel line. Edelbrock carb getting to hot. Use a spacer under it. Switch to a Holley.

I re-made the line from the fuel pump to the carb with hard line and isolated it so that it wasn't touching the block anywhere. Then I covered all of the fuel line that is near the header. I couldn't make it do it today....but it was only in the 70's today. So, I am not going to hold my breath until it is warmer.

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Originally Posted by Mikej

Sounds like it is vapor locking. To much heat under the hood. Exhaust to close to the fuel line. Edelbrock carb getting to hot. Use a spacer under it. Switch to a Holley.

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I can agree with that.

Temps were in the upper 80's Wed. and I drove the Nova to work. On the way home I did a quarter mile run. When it shifts into 2nd, it starts to surge...bad, then comes back, then I let off. Man that is frustrating! I think I am going to try one of those thick 1/4" gaskets under the carb to help with the heat. Any other suggestions?

Does it surge or bog? You could try a 1/2 inch phenolic spacer between the carb and manifold to dissipate the heat from the carb. BTW, what kind of air filter are you running?

Did a trip to town, but before I left:

1. Advance static timing 2 degrees
2. Removed the air cleaner
3. Remove primary metering rods and found them to have gouges and scratches. I polished them with steel wool.


Temps are 85 right now and I did 3 runs on the way to the nearest town(20 miles roundtrip). I did the first one on the way just when the thermostat opened before everything was heat soaked. Didn't do it.
Did one on the way home and it only did it in 3rd gear barely.
Did another and it didn't do it at all.

I think after a year of trying everything on my Nova to cure the rev problem, I think I FINALLY found the smoking gun. I took the carburetor apart again to calibrate it using the Edelbrock calibration kit. I removed both of the needles and seats and found that the last chance screen behind the seat on the drivers side bowl was plugged with crud. I also cleaned out the passage with Berryman's chemtool and blew it out with air and a whole bunch more crud came out. Put it all back together with larger jets and rods and it seems fixed. It now pulls hard all through 1st, 2nd, and 3rd. Thanks for everyones advice.

Jeff