I know that vacuum seems to be better choice, however I was wanting to know if a fixed psi set, say 20psi with a JET regulator. Then the fix psi is properly tuned in the ecm on a dyno, for proper idle a wot...

Is that even possible to do with great tune & dyno? Or will it be the better choice be the vacuum regulator?

I was about to purchase the JET regulator, in hopes of it powering my 383. with about 18-20 psi constant with a hi flow pump of 100psi!

Will the stock regulator made adjustable, be any better than the JET? or just as good? Or will it be able to output a higher psi than the JET if set up properly? I couldn't find these answers with a search.

also, 100psi pump, AFPR, and 350 injectors is that sufficient to run a 383 daily? once everything is tuned in.

 

pumps are rated in psi, any pump will make pressure. The trick is to supply volume. Any pump will make zero psi unless there is a restriction in the line, this is basically what a regulator is, an adjustable restriction that maintains a certain pressure.

With that said, a regulator is a regulator when it comes to tbi. You can get a stiffer spring to gain more pressure from topdownsolutions, which will be much cheaper than a blingy regulator from jet.

Stay away from the vacume referenced regulators unless you get the EBL system. Trying to tune for the vacume referenced regulator is a royal pain in the ****, and really doesn't work all that well. The EBL has a table that allows it to handle the varying FP.

It's a complicated subject, but basically your motor won't require a varying fuel pressure that a vafpr provides.

 

i know any pump will make pressure, but I understand the TBI is a low pressure unit, versus the high pressure TPI unit. correct? So what I was getting at his ditching the TBI pump, for a TPI or MPI pump? I had this 1 in mind: http://store.summitracing.com/partde...?part=EDL-3581
255lph and 100 psi of max pressure.

I sort of figured the JET unit was crap... I will just modify my stock unit, to a fixed psi, say 20psi, with the high flow pump. Then get it tuned in that state, at the psi.

Thanks for answering about the vacuum regulators, that sorta confused me some. I'm glad I don't need one actually.

what is the max psi the stock TBI pump will flow, granted I do the FPR mod??

 

Sorry I really didn't explain that very well. The max pressure a pump will make is completely dependent on flow.

A stock pump will reach 150 psi when feeding a weed-wacker, when feeding a healthy V-8 it won't provide much more than stock pressure.

The walbro 255 will supply any pressure you desire as long as you are making less than 500 hp.

Pumps actually have a flow vs. PSI graph the shows what they are capable of, the lower the pressure the higher the volume and vise versa.


Short answer, you need a bigger pump. The 255 will work, but be warned the TBI fuel return passages are a little small and some guys have a hard time getting the fuel pressure under 15psi, which in your case won't matter. The walbro 190 doesn't flow enough to over power the return line, but won't supply as much fuel as a 255, then again the 190 will supply enough fuel to max out any TBI system......confusing enough for ya?

 

ok, so the more restriction, the more built up pressure... makes perfect sense. Ive heard alot of the walboro pumps, but summit doesn't seem to sell them. I will settle for the edlebrock 255, even though it will be a little too much, but like you said, I need the pressure anyways.

sort of confusing, but I think I got it now...

check your PM boss, I have a unrelated question.

 

The eldelbrock is a walbro pump, everyone pretty much sells the same stuff in their own packaging.

 

cool beans.... lol

I will get that pump, and modd my regulator today......... thanks man!