Chip
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Chip
I have a 1988 f150 300l6 with 4spd and 3.08 gears. I put a crane Cam in and removed cat now I want to install a chip whats the best one and what are some good mods for the 300 l6.
what do people think about putting in a adjustable fuel preasure regulator and 20lb injectors. I have all the parts to do it is it worth while. Allso confused about the article that describes how to do this mod cause he used a adj. reg froma stang and they only go to 45lbs my factory manual says mine will max at 50lbs and idle at 40lb..whats the deal is it a miss print as I have checked my fuel preasure at idle and it was only 32lbs. This concerns me cause maybe I have a fuel system problem that need tobe fixed before I even consider more mods.
Reasone for all this is w/new cam engine is border line lean hardly any color on the plugs but the timing band is good so whats the deal or were do I go from here.
Please help??? (ohh ya I threw my Snap on scaner on and I have no fault codes everything is a ok and I purged my fuel system)
what do people think about putting in a adjustable fuel preasure regulator and 20lb injectors. I have all the parts to do it is it worth while. Allso confused about the article that describes how to do this mod cause he used a adj. reg froma stang and they only go to 45lbs my factory manual says mine will max at 50lbs and idle at 40lb..whats the deal is it a miss print as I have checked my fuel preasure at idle and it was only 32lbs. This concerns me cause maybe I have a fuel system problem that need tobe fixed before I even consider more mods.
Reasone for all this is w/new cam engine is border line lean hardly any color on the plugs but the timing band is good so whats the deal or were do I go from here.
Please help??? (ohh ya I threw my Snap on scaner on and I have no fault codes everything is a ok and I purged my fuel system)
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Joined: Dec 1999
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From: Copley, OH
Chip
Do a KOEO (key on engine off) test on the fuel pressure,you should see 55 PSI or so. If not, there's a problem somewhere but it may not be the regulator. It could also be a leaky injector or a pump problem.
The stockinjectors on a 300 are rated at 14 lbs/hr @ 39 PSI. Ford raises the pressure to 55-58 PSI which changes the thruput to 17 lbs/hr. When you change to 19 lb injectors you need to get your base fuel pressure down to 39 PSI and get an adjustable regulator to raise it back up if you need more fuel. Running 19 lb injectors at 55 PSI raises their thruput to almost 23 # which is WAY more than you're likely to need. The 19# units at 39 PSI are good for somewhere around 185-220 HP peak.
The stockinjectors on a 300 are rated at 14 lbs/hr @ 39 PSI. Ford raises the pressure to 55-58 PSI which changes the thruput to 17 lbs/hr. When you change to 19 lb injectors you need to get your base fuel pressure down to 39 PSI and get an adjustable regulator to raise it back up if you need more fuel. Running 19 lb injectors at 55 PSI raises their thruput to almost 23 # which is WAY more than you're likely to need. The 19# units at 39 PSI are good for somewhere around 185-220 HP peak.
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Chip
Okay I now have 45psi of fuel preasure at idle and when I pull off the vacume line to the fuel regulator I get 58psi. and if I snap the throttle It jumps to about 50psi. So fuel preasure problem cured.
Problem still is all the plugs have no color on them at all the procilin insulator is white (the same w/all the plugs). Before I installed the cam I had 20inches of vac, plugs had a slight (I mean slight) tinge of brown just the way I like them, I allso scaned the engine to make sure all sensors were okay and I purged the fuel system. (I own a snapon obdII scanner and a extend fuel purge kit) all was okay. Installed cam now engine seems to be lean and I need some advice on how to richen it up to put some color on the plugs. My vac after cam is still 20inches and scane came back aokay. If I put bigger injectors in and adj/reg that will give engine more fuel but wont the ecm then sence the rich condition and just adj the injector signal to compinsate? and why isnt it now? are my stock injectors maxed out know? what about just increasing fuel preasure know with stock injectors wont that richen it up?? AHHHHHH brain pain Iam getting confused!!!!!!!!!!!!!!!!!!!!!!!
Problem still is all the plugs have no color on them at all the procilin insulator is white (the same w/all the plugs). Before I installed the cam I had 20inches of vac, plugs had a slight (I mean slight) tinge of brown just the way I like them, I allso scaned the engine to make sure all sensors were okay and I purged the fuel system. (I own a snapon obdII scanner and a extend fuel purge kit) all was okay. Installed cam now engine seems to be lean and I need some advice on how to richen it up to put some color on the plugs. My vac after cam is still 20inches and scane came back aokay. If I put bigger injectors in and adj/reg that will give engine more fuel but wont the ecm then sence the rich condition and just adj the injector signal to compinsate? and why isnt it now? are my stock injectors maxed out know? what about just increasing fuel preasure know with stock injectors wont that richen it up?? AHHHHHH brain pain Iam getting confused!!!!!!!!!!!!!!!!!!!!!!!
