Tell me if I have this right...pump saver question

I agree with you that the crack pressure of the saver should be higher than the peak pressure the system sees during a run. And I agree that it is to relieve pressure on the pump when you lift. But I disagree on the part about it affecting the tuneup in any way at full throttle. I was making the point that since the saver orifice in the BV doesn't line up with the poppet at full throttle it can't affect the full throttle tuneup. Period. The crack pressure of the saver poppet at full throttle is irrelevant since it is a closed circuit. I was not suggesting that one should set the saver crack to less than the normal peak, just that it wouldn't matter if you did.

As for number 2, the point I was making was that even if the saver poppet was open at full throttle, where the circuit is closed, the clearances around the BV wouldn't allow enough fuel to pass into the circuit to have any effect on the tuneup, thus supporting point number 1, that the poppet crack pressure is irrelevant at full throttle.

Unless the fuel can find a path to the saver poppet other than the intended circuit, the saver is simply a non-issue at full throttle. That's my story and I'm stickin' to it!

 

Good point Dave. After reading your post I started thinking about the environment my engine lives in and came up with the following:

1. We bypass so much fuel here because of the bad air that making fuel pressure is actually a little difficult without going to super small nozzles. (Many times I run a 155 pill)

2. I don't spin this engine as hard as most of you guys do, which adds to the fuel pressure peak being fairly low.

3. I'm only running 11.5 to 1 compression.

As such, I don't think it's going to put enough fuel in it to hydraulic at this point. I'm actually more worried that it might shut the engine off, even though it will only be on the pump saver for about 1/10th of a second. The asphalt at our track is so old that it makes alot of gravel in the shutdown during an event. To keep the gravel out of the pipes (and cylinders, I found out the hard way), I run the engine to a dead stop and then shut off. It'd suck if it drowned out.

PS, I've got to call you and get some Prizm and some of that stuff to dissolve it too.

-Brian

 

call me anytime..prizm and bonified...IM THE CHEAPEST IN THE WORLD

 

I was just tring to insure you understand as i read on your post on your #1 you stated that it did not matter where crack pressure was set above idle and part throttle but incase someone miss judges a proper safe limit above part throttle and it opens. as for changing your tune-up it would come into play if the poppet opened up while you are staging and bringing rpms up with a 6an line and fuel pressure change at hat distribution block it would alter hat /port split that you had prior to poppet opening
, however small it will alter your tuneup for that launch. How it is going to affect your launch i do not know. so to some it up i believe it alters the balance you got to get egt's and piston temp for proper launch. i hope this helps you understand my thoughts

 

http://www.maddernracing.com/largeimage.asp?ImageID=10&GalleryID=1

Looks to me like the pump saver is tied into the 'port' outlet on the back side of the barrel valve with an additional popet, return, and a pressure transducer. Manzo has a similar setup. Makes you go hmmmmm.

 

OK, now I understand what you were saying. We agree.

This has been a great thread. Thanks everybody. This is what makes this such a great forum.

-Brian

 

I will agree with you as it appears to be that way. it may be possible but unless we see where all the lines run that are attached we can only assume this to be the case. I would like to see his system . I am just going by my understanding on what i have been taught and how i feel safe to do. Like i posted before these systems are complex and this is a good forum for getting advise to help , However people will sometimes have different understandings and it is up to them to do decide on which advise they try as its someone's knowledge. If one person knew it all no use us racing cause we would never win. I know that there are many people that have replied to my questions that have helped me I am just trying to do the same .

 

Truth be told, this picture is what got me thinking about the bypass line so I know it works but wasn't sure if it caused any other issues. I saw it a couple of months ago from a link from this site. Anyone know this car from Div 1? Maybe they could tell us how it works?



I think any bleed past the spool can be compensated for in the tuneup.

 

I had mine the same way,bottom of the B.V.
Seen several guys plug them so now mines blocked off completely

 

monkey see monkey do

monkey see monkey do

 

monkey see monkey do

are these words --------bullets fired at someone? (me)
d jackson