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Only 32 PSI with 125s and compounds

2K views 18 replies 6 participants last post by  Clunk 
#1 ·
First post, any help is appreciated. My truck is a 2001 5 speed 240,000 miles. Has a Fass 150, BD injection pump, Edge Juice w/ Attitude, and stock over (i think) ~S300 compounds. I just installed 125 horse BD injector nozzles and have gotten almost no power gain over the nozzles i just took out, which I am 90% sure were stock. If I pin it from 1200 RPM in first gear itll blow a short cloud of smoke but then quickly cleans up around 15 PSI. PEAK boost is about 32. Ive read on other posts that people are making that if not more with 60 horse injectors. When I bought the truck it had the juice box under the hood but someone had removed the screen. I then bought a kit from Edge that included just the screen and noticed a small increase in power. Something is telling me the computer is not dumping fuel like it is supposed to even on the 5x5 tune. From a roll in any gear the exhaust is completely clean. So my question is why is the truck not pulling hard with 125s and compounds and peaks at 32 psi. Thank you all, I find myself on this forum almost every week, so figured I go ahead and ask the experts.
 
#3 ·
Its an S366 I believe. It was on the truck when i bought it as a single. Other than that dont know much about it. Didnt spool at all till around 2300 then would light up to 25PSI. Then I added an HX35 in a compound setup which spools fast and peaks around 30 PSI until I added these 125s, now I peak at ~32.
 
#7 ·
Ive checked for boost leaks and beleve im good. Dont know drive pressures becuse I dont have a guage for it yet, that and a fuel pressure guage are on the list.
Also check map sensor.
MAP sensor seems okay, it is spot on with my mechanical boost guage, could that be the problem if say it was only reading up to that 32 PSI?
Check the HX35 wastegate as well.
HX35 wastegate is pinned shut. How could this affect the low boost im seeing.

Reply for all. I cant help but think its an electrical issue. Maybe my programmer is not "compatible" with the box under the hood? Theyre both edge but i did do a roundabout way of making it work. When I called edge they said the box I had was discontinued so they couldnt help, so I went to another distributor that had JUST the screen, sold as an "upgrade kit" for people who had the small edge screen with the buttons and wanted the touch screen. But with all this being said all the gauges work on the screen and there is a difference between all the tunes.So I know its changing fuel an/or timing somehow. Could it be possible its changing ONLY the duration of the injection? and not actually pushing more volume for a given duration? <- If that makes no sense school me, I'm new. It just doesnt seem like its fueling the way it should. Gonna go out and run a check on all the connectors shortly. Thanks everyone for all the replies so far.
 
#9 ·
You're going to want the waste gate functioning with compounds. Is the vp44 wire tapped? The edge situation sounds overly complicated. maybe you could sell that all for a decent price and get a Quad.
 
#10 ·
You need to stop throwing parts at it and test for boost leaks, verify the injectors are good and popping right ( who built your injectors? what did they set pop pressure to?), verify your wastegates are setup right.

Pump the breaks and figure out what you actually have and verify everything is good and working right. 125's are tiny injectors for that setup,

The quad is great, but it won't magically fix issues.
 
#16 ·
You need to repop injectors after doing nozzles. Who's to say what they were popping before the nozzles.

I'd start by getting your boost fixed and doing a boost leak test to fix your other leaks. Then I would get your injectors repopped, and verify your nozzles are working like they should.

Then I would relook at how the truck is running.

as for running clean 125's are tiny for the air your setup can provide, even with a big boost leak.
 
#19 ·
The Edge VP44 pump wire connector often fails to stay connected, I soldered mine.

I get 40psi with my setup.
 
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