If you prime the carb enough to get the car running for a second or two it should work all the air out of the line....you could also fill the float bowl through the vent to give it enough fuel to run for.minutes.... you only used grease to hold the rod in place, you didn't use the bolt through the front of the block?

 

It was my understanding that the BB doesn’t have that?

 

A) Carb needs primed
B) Fuel pump Cam lobe is wiped out
C) Small block fuel pump

If A doesn't fix it, check the other two

 

It does

 

Update, I’m still not getting fuel pressure. I verified the part number and removed the pump to make sure the rod, etc is correct. I re installed, primed the carb five times but no fuel pressure.
This vette was starting very well but had power issues due to low fuel pressure.
I do have good, fresh fuel flow to the mechanical fuel pump.
When I first installed the pump the rod was pretty loose now it seems to be pretty tight, not sure if there is an issue there.
KC

 

Is there good fuel pump rod movement when the engine is cranking over.....careful watch those fingers

 

It does move out to the “full” cam position. It does not return easily.

 

either you flattened the pushrod tip and its mushroomed, you tightened the bolt in the front of the block onto the pushrod or you somehow misaligned the pump arm on the pushrod

 

'Mild roller cam"
What brand?
What type of core?
What type of fuel pump pushrod? Steel, polymer or bronze tipped?

 

Comp cam, I didn’t discuss the pump rod material during the build but it looks like steel. Here is a picture of the cam specs.

 

Big blocks (LS-5=454) do not have the same "holding" bolt arrangement that small blocks have.

 

1) While you have that setup you could drop the open hose end into a bucket and crank it and see if the fuel pump is giving you fuel flow.
The only pump spec I know of is about ~1pt in 60 30 seconds.

Since you have a new fuel pump and still no pressure I would pull it again. PITA. I know. Sorry.

2) On dissasembly check very carefully as it comes apart that the pump lever is sitting on the end of the pushrod, and not stuck beside it or behind the tip.
Look for scratch marks in the wrong places confirming this.
Pull the fuel pushrod and examine it's ends, and for straightness.
It should slide out easily, or with a magnet if you have a lot of grease in there.

3) I checked the part # also, it says it is for a big block. But there is always the possibility it is boxed wrong. Do you have a known good BBC pump or SBC pump to compare it to? Look at the arm curve and length, they are different. Or post pics here with a clear view of the arm. A SBC pump will do exactly what you described ~1 psi. That was the ultimate fix on the red 454 vert in my earlier post. 3 SBC pumps in a row! They barely worked and it barely runs.

4) If nothing yet, then I would check that you have at least 1/2" of pushrod lift from the cam lobe as the engine is turning over.
Be careful with your fingers in there.
Or check while still but at several 90* spots.
If you are suspect about the lobe lift find a way to measure it with a dial indicator.

IIRC the -8 means it is the standard & softer "austempered" cam core.
You may have a flat cam lobe, on the pushrod lobe.
We can always find a way to give you a spec measurement on what the lift should be.
IMHO steel and bronze tipped pushrods have suspect reliability on roller cams.
I would put the Howards carbon fiber ceramic polymer pushrod in there, it was developed for Nascar and roller cams.

At this point I have to believe one of those 4 tests should pinpoint your issue, on why you have no fuel psi.

BTW with that cam I would expect near 425-450HP on an otherwise stock LS5, CR depending.
You said you had it dyno'd.
Result??? Inquiring minds want to know.
And did they use an electric pump on the dyno stand? Most do.

 

Leigh1322, to update my fuel pump rod is sticking . Im thinking this was the problem and not the pump itself. Im currently working on getting the rod out.
We didn’t do a lot of tuning on the dyno but thru factory exhaust manifolds (no mufflers), original quadrajet, intake manifold it was about 389hp and 479 ft of torque. 9.5 to 1 CR.

I looked at some pictures and we did use an electric fuel pump on the dyno. Probably should have used the mechanical as this issue may have surfaced.

The current pump rod has too much resistance to be pulled out for replacement.
KC

 

Pull it out as far as you can install a block off plate and use an electric pump.

 

That sounds like a mushroomed tip to me, on a bronze tipped fuel pump pushrod. Unfortunately I have heard that story too many times.
Race car part; not good for the street.

 

Update: I finally removed the stuck fuel pump rod, replaced it and the fuel pump. I really liked the odds that this would help with the power issue. I did a test drive and no improvement. I then hooked up my fuel pressure gauge and noted the fuel pressure was 0 at idle and with the engine RPM increased. The fuel gauge is new but I’m thinking it may be faulty? The car does drive fairly decent so I’m thinking it has to have some fuel pressure. I’ll probably test with a different gauge and go from there. There is a picture in the thread to see my test set up.
KC

 

Can you post a pic of the fuel pump rod at the end where it may have been sticking?

 

Can you post a picture of your test setup with the fuel pressure gauge?

 

Here is the requested pictures. I haven’t measured it but the end doesn’t appear to have mushroomed. The engine and pump rod only has a few miles.
KC

 

You have a couple things to resolve.

1. Why was the pump rod sticking?
   • Does it roll flat on a piece of glass?
   • That looks like a wear mark on the tip that suggests it was not rotating.
   • Is that a wear mark on one side only 1/2" down from the tip? Better pic?
2. Why is the fuel psi low?
   • Double check the gauge with another gauge, or on another good running engine. You must know if it is accurate. Do you have an air compressor or hand pump or a Mity-Vac hand pump that you can use to double-check the fuel psi gauge with another gauge?
   • Is that a fuel injection gauge kit? It may not read at 5psi at all if the gauge goes to 100-150psi. You could put another gauge on it. 0-15 psi or 0-30 psi one. for a carb.
   • If 0 psi, it is either pump or cam lobe. The pump could have very low flow and do that.
   • Run the pump outlet into a container to be sure it also has good flow. Around 1 pt @ 30 sec. Fill the carb bowl thru the round vent on top and the engine should start and run fine for ~30 sec. with no fuel line attached. Maybe 1/2lid of a paint can spray lid of gas should do it.
   • Deadheading the pump should give you psi. If the bowl is full, the needle & seat should block flow, and you should get 5-7psi. Fill it with a squirt bottle or your paint can lid. You can even plug the pump hose outlet if necessary. The engine should run for 30 sec on the bowl and that is more than enough time to get a reading.
   • If you still do not have any answers, spin the engine (starter button) no gas or ignition, measure the pump rod lift with your finger or a tool, it should be near .330" Let's hope the cam lobe is not bad.

This stuff is not complicated, it is just figuring out how to test it and confirm that takes some ingenuity.