Got my car running this week and am having alot of problems. I changed the in tank pump to a walbro 255 and am running a Mallory FPR. At first i would have to change the FP what felt like every time i started it now it will not drop below 9 i can take the screw right out and it wont go below 9. The only things changed since it was running at 6.5 was it now has a 1/2 tank of gas and i changed the jets so im pretty pissed.

 

TTT I really want to drive my car please someone give me a hand

 

I live near flint Michigan if anyone is local that wants to take a closer look. I will pay for gas or whatever i just want my car on the road.PM me for my number

 

Make sure your return line doesn't have any restrictions, such as an adapter that's too small.

 

I have a elbow that comes right out of the regulator. But like i said it was fine it would hold the right pressure until i changed jets and and put more hen 1/2 tank of gas in it.

 

I guess I don't understand the chain of events. I was under the impression that it wouldn't keep a steady pressure after you changed the pump.

 

It was ok then just one day the pressure wouldnt drop below 9 psi. Today i went out a bit ago and its fine???? i dont get it im going to change the diaphram even though the regulator is new.

 

That still sounds like inadequate return flow.

 

we will find out tommorow i have a new regulator coming under warranty if i get the same **** ill have to run a big return line

 

Ok so the surging out line stuff is gone but my pressure is still constantly changing ill set it drive for 10-15 minutes and its different. Usually it will go down i dorve for a bout a hour the other day and then it started acting funny and i opend the hood pressure was at 0 i had to adjust back to 6.Will heating of the gas say from my dual exhaust cause this constant change in pressure?

If i cant figure this out before week out im putting a pick up tube in and going to a external pump or maybe try running a new return line.

TIA

 

Are you revving it up for a bit while setting the FP?

I know guys that just set the pressure and go, then have issues like this because they didnt rev it up a bit to allow the gas in the bowls to go down low enough to allow fresh gas into the bowl giving a true reading of the pressure...

 

Are you using the vacuum port on the reg? It is only needed for supercharger applications.

 

Ill give the reving and setting it a shot. Im not using the vacum booster thing. Ill let you know how it works out.

Here is a clip of my car running http://media.putfile.com/383-stroker-iroc

 

please note in the clip the vacum port was hooked up because i was desperate trying to get something to work. I later found out that it was not helping

 

Well i cant wait any longer im tired of dealing with this problem im going to buy a holley blue and regulator put a pickup in the tank and figure something out for a filter. Anyone intrested in a 20 minute used Walbro 255 and a mallory fpr let me know