Im thinking about installing a higher flow mechanical performance fuel pump. Can it cause any damage, say to my carb or anything else? Does it have to have a fuel return system used with it. In addition to re-routing the fuel line to help with a vapor lock/low fuel supply issue, I was thinking about making this upgrade as well. I just want to make sure that it wont hurt anything. What say you?

Car is a '71 Satellite, 360/904, 600 cfm eddy #1406 carb, eddy performer intake, stock replacement points dizzy with Pertronix Ignitor 2 system with Flamethrower 2 coil, Bosch Platinum plugs, I run 93 pump gas, 2.76 rear gears...

thanks
roe

hi
i would use one that has a psi no higher than 6.5 for a street car .

looking at the part details, its says that the max psi for the high flow is 7.5 psi and max flowrate of 80 GPH.

The stock replacement is listed at 7.5 psi and max flow rate of 30 GPH.

Heres what I found while looking:

Airtex Stock replacement: 30 GPH max flow 7.5 psi $22

Holley: 80 GPH, 7.5 psi $86

Holley: 110 GPH 6.5-8 psi, $127

Edelbrock: 80 GPH, 7.5 psi $79

Edelbrock: 110 GPH, 6 psi $140

With a stock replacement being 7.5 psi, would it be safe to get the 80 GPH Holley at 7.5, or should I spring and pay the extra for the Eddy 110 GPH at 6 psi?

roe

for 1, you need to be running a fuel pressure regulator with that eddy carb, so that the carb sees no more than 5 psi.
and 2nd, i have built,and ran many,many high 11- low 12 second street/strip big-block cars running stock,airtex/carter replacement mechanical fuel pumps. just don't see that combo of yours needing more fuel volume or pressure than a stock fuel pump supplies.

Get that fuel line heating issue taken care of and you should be good to go.

650 Eddy will not like much more pressure than the stock pump provides. What problem are you having? How thick of a gasket do you have below the carb? Should be at least 1/4" thick, even better a 1/2" thick 4 hole phenolic or wood spacer if you have enough room to still get your hood shut.

didn't know that I needed a fuel pressure regulator with a stock pump, will look into getting one though.

fuel line will be re-routed tomorrow, just was trying to do my homework on whether a higher volume pump was a good idea, and if so which one to run. I guess that's how I should have worded it. I guess I figured that a higher volume fuel pump would also help with my issue and be a good upgrade if the carb can handle it.

fuel line will be re-routed tomorrow and then go from there.

The stock "airtex" will b plenty of enough flow for you just take care of the prior heat soak prob. I cant see the airtex having 7.5 psi & I would put your vac gauge on it at the carb inlet at idle to check as most have a fuel psi side & if it does show that much actual you'd need to regulate it down.

just out of curiosity what happens when a carb sees too much fuel pressure?

on an eddy carb,the excess fuel pressure (over 5 psi) pushes the needle off the seat,and the fuel runs out 2 bowl vent holes in the front venturi face of the carb. the extra fuel can cause a slight to moderate dead spot right off idle,and a rich condition at idle. will also cause the engine,after it has been ran and up to operating temp,on restart,you will have a seemingly flooded issue,where you have to push the throttle down quite a bit for the engine to restart. any of that sound familiar?
most stock,parts store mechanical pumps will put out between 6-8 1/2 psi. even a 150,XXX mile stocker can still be putting out 6 or more psi of pressure.

If my fuel pressure is too high and causing the issues with my carb, will it go back to normal after installing a fuel pressure regulator? Or will the carb need to be serviced/replaced in addition to the fuel regulator being installed?

Man I had no idea a stock airtex type would put out that much psi and I'm having "some" of those symptoms on my Eddy 1406. Better dig out my vac gauge & find out

Roe,i have one of the small cheapy regs from purolater you can have to plumb in your line

it took care of the pressure on my edelbrock carb

PM your addy if you want it

re-route the line,add that in and give it a try.shouldnt have to replace the carb but may need to re-set the float level

it worked great with my stock cheap autozone fuel pump

Look at the last Q&A on this page:

http://www.edelbrock.com/automotive_new/misc/tech_center/install/carb_faq.shtml

Well, I noticed that lately I have been guilty of something that I hate to see happen...Someone not following up on their own thread with updates after recieving help from board members. Most of the time thats how I learn about new things, by following threads that ask for help, and reading the updates as to what helped solve the issues. So Im going to start following up on my own threads, starting with this one.



Thanks again to Scratchin for the fuel pressure regulator. I have that plumbed in line now, and set at 4.5 lbs of pressure. That helped some with the issues I was having. Mainly it let me be able to tune the carb better with the idle mixture screws when it stopped the pressure from pushing too much fuel at idle. Before the reg, the idle mixture screws really had no effect.

Next I also installed the cooler temp thermostat at 180 deg which has helped to keep the engine bay, and therefore the fuelpump and carb cooler. I also kept the stock fuel pump which is performing fine.

The car was still not where I thought it should be, namely because of the slight off idle bog.

So I focused on timing. I began to bump up the initial timing and the motor ran better and better. The higher the initial timing got, the better it ran, the smoother the idle, and the smaller the off idle bog until it disappeared. In dont know exactly what the timing is at now, but the timing mark is high enough that I cant see it on the balancer when using the timing light. My last adjustment was a little too big, so Im going to slowly back it down to where I want it. I hear a wierd noise that I cant really describe, when under heavy acceleration that was never there before and I think I just went a little to high on the initial with my last adjustment. Its kind of a metallic, pinging kind of sound.

But the motor is definately running stronger, its breaking the tires loose a lot easier. Also, as the timing was bumped up, my vacuum reading also went higher, at idle in park and in gear, and the idle quality is much better. With the higher vacuum readings the brakes are better. And my cruise rpm at 70 mph seems to have went down, but I'll verify that later. It started to rain and I didnt feel comfortable testing it out on the wet road.


Question: with me bumping the initial timing up, do I need to try and limit the total advance of the dizzy somehow? Its a stock replacement single points dizzy with a Pertronix Ignitor 2 kit and Flamethrower 2 coil. I've never fiddled with the advance curve in any dizzy before. I just dont know if advancing the timing by turnning the dizzy changes the total timing, or just the rpm at which it comes in.

set the initial w the vac gauge method then yes shorten the slots to get 35 (SB) then work w the springs esp as the sound you are hearing is pinging & is very damaging, stay out of the throttle till you get it squared away, then hookup/tune the vac adv (if used).