Wondering what I should set my adjustable fuel pressure regulator at when I install the Accel 17# injectors in my 3.4L crate engine. Should I set it at the speced 40.5-47psi shown in the shop manual for the 2.8L? I have a pressure meter on the fuel rail and it's an 88 GT. Thanks for any help.
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02:08 PM
PFF
System Bot
avengador1 Member
Posts: 35468 From: Orlando, Florida Registered: Oct 2001
ideally, you want to set it by reading what the ECM is working with - cant remember if a low BLM means you need higher pressure or the other way around...
Those 17 lb injectors are more then enough for a stock or even slightly modified 3.4
And for anyone thinking they need 19 lb injectors on a stock or even modified 3.4 forget it. Way too rich. I am talking like 11:1 rich. First hand experience with using 19 lb injectors.
If you don't have a way to read real time data/what's going on inside your engine via the sensors then the best way to do it is to set it by "ear'. Every engine is different. Be very anal about setting it. Little minute adjustments, then drive and see how it behaves, then check the plugs, then repeat until it's right. It works, i've done it and helped others do it this way and, if you do it right, you can get rid of the hunting idle and have a very well running car.
------------------ Activities Director N.I.F.E. www.fierofocus.com
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11:59 PM
Aug 31st, 2004
Electrathon Member
Posts: 5241 From: Gresham, OR USA Registered: Dec 2002
ideally, you want to set it by reading what the ECM is working with - cant remember if a low BLM means you need higher pressure or the other way around...
You want the BLM to be as close as possible to 128. If the number is high you are running lean. If low you are running rich. There is no way of knowing that it is slightly off unless you are seeing scan data. The computer will adjust for the problem. The system will work best though when running correct.
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01:40 AM
Black-Azz-GT Member
Posts: 2326 From: Florida Keys Registered: Oct 2003
im not 100% sure on this so someone correct me if im wrong.
but just cause say a GM injector says 19lbs, doesnt mean that a ford injector at the same PSI will also be 19lbs does it?
are the injectors rated by what the PSI they are supposed to push?
that whole sentence above probably didnt make since but who knows.
i ran the stock 17lb injectors in my 3.4L and it ran VERY rich, with my stock FP, when i switched to mustang 302 injectors, with stock FP it had 128 on the BLM and didnt seem to be running rich anymore.
matthew
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12:45 PM
fierobear Member
Posts: 27106 From: Safe in the Carolinas Registered: Aug 2000
I'm having problems with my 3.4, and I'd like to figure this out.
I've tried 2.8, 3.4 and 305 injectors. Right now, I'm running 3.4's and I'm still having problems.
Recently, a friend of mine put his scan tool on my car and we went for a drive. He says it is running very rich at idle (I have the hunting idle, +/- 500 rpm), and it is running very lean at cruise. Block learn is at 60. TPS and Oxygen sensor voltage doesn't seem to change much (TPS is new).
He said that the fuel pressure should be set to stock (and that I should put the stock regulator back on). Turning it up won't help. The injectors aren't delivering the right amount of fuel, and the ECM can't keep up. The car won't pass CA smog check II, with very high NOX. The EGR solenoid and valve are new. Vaccuum has been thouroughly checked, no leaks. There are no engine codes.
I'm having problems with my 3.4, and I'd like to figure this out.
Right now I am using 17# injectors that are pintle type. From reading the archives, the stock 2.8 injectors are pintle so you need to make sure the new ones are also pintle type otherwise the computer can't control it properly. There was only one person out of many that could get the other style injectors working right. I am also using the stock regulator. The engine takes about a minuite to warm up a little and then has a solid idle at 1100. I just finished the motor in May. During the buildup I spent lots of hours reading in the archives different peoples opinions on this subject and this is what I came up with. I have also taken sensor data and sent it to Darth and he said that it was pretty close to where it should be at. I think that I may get a chip burned later, but for right now it is running great. -Mark
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01:26 PM
fierobear Member
Posts: 27106 From: Safe in the Carolinas Registered: Aug 2000
Right now I am using 17# injectors that are pintle type. From reading the archives, the stock 2.8 injectors are pintle so you need to make sure the new ones are also pintle type otherwise the computer can't control it properly. There was only one person out of many that could get the other style injectors working right. I am also using the stock regulator. The engine takes about a minuite to warm up a little and then has a solid idle at 1100. I just finished the motor in May. During the buildup I spent lots of hours reading in the archives different peoples opinions on this subject and this is what I came up with. I have also taken sensor data and sent it to Darth and he said that it was pretty close to where it should be at. I think that I may get a chip burned later, but for right now it is running great. -Mark
I don't think it is the computer the problem but the programming of the PROM. I'm running disc type with custom PROM and they work perfectly. My FP is around 43.
Right now, the 3.4 injectors are in. Are they pintle-type?
If they are the 3.4 Camaro injectors then I think that they would be the disk type and not the pintle type.
Alex4mula: Well I'm glad that it works for a few people. Maybe most people using that setup just can't get the prom burned correctly. Out of all the searching through the archives I only found 2 or 3 people that it worked for. I think you were one of them. I'm just trying to point out what worked for me.
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05:34 PM
82-T/A [At Work] Member
Posts: 25624 From: Florida USA Registered: Aug 2002
