Using stock Delco mech. fuel pump for modified 350 small block. Appear to be running out of fuel 3rd gear near 6000RPM. Have new 3/8" fuel line and large clean fuel filter. Anyone using Edelbrock pump 1721 or 1722 without crossmember interference? Don't want electric pump if possible. Any suggestions appreciated.
Thanks
Tom Sholl

I had one on my engine with 0 interference issues. They say they make 6psi, but I recommend a regulator.

Get a Carter high volume pump, about $75, will fit without frame interference like those 6 valve types.

I never had any issues with the Edelbrock 1721, but I did need or should I say, felt peace of mind with a regulator.

I run a Holly pump http://www.summitracing.com/parts/HLY-12-834/ with a regulator and no clearance issues on my '67 They are rated at 7.5 PSI and 80GPH.

Using stock Delco mech. fuel pump for modified 350 small block. Appear to be running out of fuel 3rd gear near 6000RPM. Have new 3/8" fuel line and large clean fuel filter. Anyone using Edelbrock pump 1721 or 1722 without crossmember interference? Don't want electric pump if possible. Any suggestions appreciated.
Thanks
Tom Sholl

I am experiencing a similar issue - I think. I was wondering how you determined that it's a fuel pump issue instead of carb issue (float level/jetting/etc...)? I also have a stock Delco which I replaced about 1 year ago. I am thinking about installing a nice fuel pressure gage in the car so I can monitor. I guess fuel pressure dropping while in third gear w/high RPMs would lead me to believe there is fuel starvation due to pump.

Cant go wrong knowing with a gauge. When i first started running my sig combo, I had a stock off the shelf auto zone fuel pump, because I was going for the sleeper appearance. At the time I was running Low 750's in the 1/8th. I didnt see a bit of change when I went to the higher flowing Carter style pump. Just a little food for thought.

Matt:
I'm using the Innovate LM-1 & G4 gauge wide band O2 sensor fuel/air monitor which indicated about 16% F/A in 3rd gear 5600RPM. Changed secondary jets from .101 to .104 with no chg to F/A. Edelbrock says their 650 AVS using .098 sec. jets should be ok with my engine configuration. Didn't monitor F/A in 1st or 2nd being a little busy going down the strip. I am using a 2004R auto trans fortunatley.
Tom Sholl

I had the same issue on the '69 running out of fuel on a 1/8 run. Turned out to be the sock on the pickup in the tank was all screwed up.