So I thought I'ld revisit this. I am not convinced the Accufab regulators are the way to go. I had vacuum leaks in the threads and lost pressure immediately after shut off. At boost the pressure was choppy too. This was after sending it back to them to rebuild it too. So here is a back to back to back comparison of the Accufab, Bosch 237 and the Kirbans regulators. The numbers in the box for the Bosch 237 are not correct but the graph shows the story.
Accufab:
View attachment 225584
Bosch 237
View attachment 225585
Kirbans
View attachment 225586
So, the Bosch is the steadiest of all three but the base pressure is 45 line off. If your chip can adjust all the fueling aside from WOT (unlike the TT 6..1) then this looks like it's a winner. If you need to adjust the pressure to 43 then the Kirban's one beats the Accufab in my test. I would like to see others do this test to compare to my results. For now I'm going with the Kirbans. If I change chips to the SD2 then I would definately give the Bosch a try, Ebay has them for $50.
Thanks pronto. PM send.PM me your address and I'll send the Accuflub to you.
Hey Pronto,
Based on data from Ponto it sure is strange.Interesting stuff here Jerryl. The design of the stock Bosch regulator is a bit different from the aftermarket regulators. Subtle differences at that.
I run a fuel pressure transducer and log it, with an Accufab FPR. The pressure does jump around, I thought that this was due to the pressure fluctuations of the positive displacement pump(s). Now I'm not so sure, need to post filter the heck out of the data to smooth it, even with a tiny orifice at the transducer (mechanical filtering).
RemoveBeforeFlight
That might be why when the pressure rises the fluctuations get larger. The Accufab website does not give the pressure specs that the regulator is good for. Maybe they just spec'd it for 15psi and not more? For retail price of $159 on their website you would think the regulator would be high quality and stable at higher pressures-NOT.At first sight, there are a few design issues as well, and I can see why the pressure would be unstable. The pressure pulses from the fpr inlet hit the diaphtlram and definitely work against the spring and will cause "chatter", especially against a weaker spring.
I will verify and confirm with my Team.