New idea for piston pump upgrade!

[darestie]

So I really want to convert to a piston pump before I install a 366 spring. I'm a little sore about spending the $190, i'd much rather find a way to make the $90 2nd gen pump work without spending a fortune on a regulator. I ran across this write-up on making a homebuilt regulator for around $20. It would require a bit of experimenting in order to get a spring/shim pair that would hold a target 15psi, but it's a pretty simple concept. I will run the return line back into a T in front of the LP. PLease share your opinions/suggestions.

Here is the write up link
http://www.cumminsforum.com/forum/general-tech-articles/17179-homebrew-fuel-regulator-bypass-valves.html

[Ace]

I wouldn't risk the front seal on the VE for something like that. You are going to have $25-30 in it after you buy all the brass anyway. Just get a real regulator.

[RSWORDS]

I run a mallory regulator that was $99... Works VERY well.

[burnt_servo]

they have a steel ball bearing as a check valve ,mated against a brass fitting for it's sealing surface .

my concern would be the bearing pounding out the brass sealing surface .

maybe replace the brass piece with a piece of stainless , then use some lapping compound to lap in the bearings profile into the new stainless sealing surface .


with that said , what is your time worth ?
what do you do if it fails on the side of the road ?

[ZSkibo]

I 2nd the Mallory. No problems thus far and I get boost referenced fuel pressure.

[PToombs]

Don Tank on here said to remove one of the springs and it would lower the pressure. I've never done it, so I can't say for sure, but it might be something to look into.

[dragrdan]

Actually what Don said was to switch the spring from the low psi pump(or one of equivalent pressure) into the hi psi pump.

[darestie]

Those Mallory regulators are designed for gas, would running diesel be a problem?

Can you buy just the low pressure spring from cummins? Then I could just swap it out.

I may just do the Mallory regulator, can someone post a picture of how they ran the lines and what fittings they needed? Thanks.

[dragrdan]

I don't believe you can get just the spring, but if someone has a low psi pump sitting around, maybe they can pull the spring, measure it, and get the spring rate?

I do know that the 2nd gen lift pump is a higher volume pump than the low psi pump, so that using it(either with a regulator, or spring change) has that as an added benefit.

[ahale2772]

I 3rd the mallory , it works great and is cheep zskbro has a post called "my new fuel system"

[dpuckett]

Ok, If you buy a $90 lift pump, then put on a $100 Mallory regulator, arent you back up to the $190 that the original poster is trying to avoid?

I think you can buy the springs independently to switch from a high pressure to low pressure. I'll ask Don if I think of it.

DP

[dragrdan]

Ok, If you buy a $90 lift pump, then put on a $100 Mallory regulator, arent you back up to the $190 that the original poster is trying to avoid?
I think you can buy the springs independently to switch from a high pressure to low pressure. I'll ask Don if I think of it.

DP

Yes, plus extras(plumbing to adapt it in), but you do get the added benefit of a higher volume pump.

Ideal low cost would be the 2nd gen pump with a low psi spring tho.

[ahale2772]

I think the low psi spring might make the pump lazy though, being that its a higher volume could be wrong...all I know is that alot of guys that have the 15 psi pump say they can still bring them down to 5 or less psi at WOT...I'm having trouble keeping my pressure to a minimum of 15 at WOT ...thats worrth the extra money in my mind...do it right once id say

[Ace]

...all I know is that alot of guys that have the 15 psi pump say they can still bring them down to 5 or less psi at WOT

That problem is the plumbing, not the pump. Show me one who upgraded or replaced the in-tank pickup. You can install as big of lines as you want, 1/2", 3/4" ten inch, it don't amount to a hill o' beans if it's still sucking through the 9/32" pickup inlet hole.

[dragrdan]

I agree 100% with Ace. If you havent done something with the pickup in the tank, every other fuel system mod is for nothing. You can only flow as much as the littlest flowing part of the system, and that is it.