new cam / exhaust / maf-sefi-ecu upgrade follow up
08-14-2011, 11:26 AM
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new cam / exhaust / maf-sefi-ecu upgrade follow up
Hey all, A while back on here I posted pics of my 89 f150 5.0 upgrade
- Summit shorty headers, welded to 2 1/4 true dual with thrush turbos (no cats)
- Comp cams single timing chain kit
- Summit 4400 CAM (windsor firing order)
- Comp cam lifters
- meiling (or whatever) push rods
- A9s cpu
- cpu matching MAF
- Custom y-pipe for intake side w/cone filter (spectre)
- New injector o-rings
- MSD Distributor / coil (12 degree advance)
- Regular autolite coppers
I was very meticulous in the SEFI wiring and the truck has left/right bank 02 sensors absolutely no smog with everything blocked off and an egr delete plug. NO CEL's whatsoever as well.
Since then I have added an electric fan , and an intank airtex mustang fuel pump in place of the old transfer pump and am running 5/16 fuel line strait to the filter bypassing the old "hi pressure" pump and diaphragm" I routed the return line the same way but I think i used 3/8 line I don't remember.
Basically the truck was running like crap for the longest time at idle but smoothed out in the higher RPM's. I finally got tired of it and decided to try messing with the fuel pressure regulator. at idle the fuel pressure with the vacuum plugged in would sit at around 30 psi and fall to like 25 even after the new pump/lines (btw this did the same with the old stock pump setup). So I figured ok its time for a new FPR .... Well it does the same dam thing...after I installed the new one..
Idle is choppy and the engine coughs and studders on itself however...When you unplug the vacuum from the FPR and plug the line it runs like butter. PSI shoots to around 40-45 and can idle just above 500 when warm without even the slightest hicup....
Also the TPS has been adjusted to .99 w/the throttle fully closed. So do you guys think with having a mustang ecu but with the truck intake/bigger cam/less restrictive exhaust the ecu is actually calling for more fuel and its time to get an adjustable regulator? I don't think my MAF is to far away from the intake but...the physical intake volume being larger now its getting confusing to figure out. I thought the stang ECU's could compensate.
- Summit shorty headers, welded to 2 1/4 true dual with thrush turbos (no cats)
- Comp cams single timing chain kit
- Summit 4400 CAM (windsor firing order)
- Comp cam lifters
- meiling (or whatever) push rods
- A9s cpu
- cpu matching MAF
- Custom y-pipe for intake side w/cone filter (spectre)
- New injector o-rings
- MSD Distributor / coil (12 degree advance)
- Regular autolite coppers
I was very meticulous in the SEFI wiring and the truck has left/right bank 02 sensors absolutely no smog with everything blocked off and an egr delete plug. NO CEL's whatsoever as well.
Since then I have added an electric fan , and an intank airtex mustang fuel pump in place of the old transfer pump and am running 5/16 fuel line strait to the filter bypassing the old "hi pressure" pump and diaphragm" I routed the return line the same way but I think i used 3/8 line I don't remember.
Basically the truck was running like crap for the longest time at idle but smoothed out in the higher RPM's. I finally got tired of it and decided to try messing with the fuel pressure regulator. at idle the fuel pressure with the vacuum plugged in would sit at around 30 psi and fall to like 25 even after the new pump/lines (btw this did the same with the old stock pump setup). So I figured ok its time for a new FPR .... Well it does the same dam thing...after I installed the new one..
Idle is choppy and the engine coughs and studders on itself however...When you unplug the vacuum from the FPR and plug the line it runs like butter. PSI shoots to around 40-45 and can idle just above 500 when warm without even the slightest hicup....
Also the TPS has been adjusted to .99 w/the throttle fully closed. So do you guys think with having a mustang ecu but with the truck intake/bigger cam/less restrictive exhaust the ecu is actually calling for more fuel and its time to get an adjustable regulator? I don't think my MAF is to far away from the intake but...the physical intake volume being larger now its getting confusing to figure out. I thought the stang ECU's could compensate.
08-15-2011, 01:36 PM
#2
broke white boy
sounds like you answered the question yourself. if it runs better at a higher fuel pressure. get an adjustable one and see if that takes car of it.