TBI Spacer 2brl Non Whistling version
- Thread starter cbmind
- Start date
Bill USN-1
F.I. Moderator
Biggest problem I see is you are real Rich.
What motor do you have and what are the numbers on the injectors. See parts FAQ to determine.
What is the fuel pressure? Is it constant?
Your charging system looks good.
The idle screw could be increased a little to lower the iac at idle and get the tps closer to 0 at idle.
The chip looks very familiar. I think I May have the original somewhere in my files.
What motor do you have and what are the numbers on the injectors. See parts FAQ to determine.
What is the fuel pressure? Is it constant?
Your charging system looks good.
The idle screw could be increased a little to lower the iac at idle and get the tps closer to 0 at idle.
The chip looks very familiar. I think I May have the original somewhere in my files.
Orange (55lb hr)? It's a 345 stock innards afaik, Holley duraspark, 8 pin module, 35" tires, 3.73 moving to 4.56 soon I hope, dual exhaust bosch 3 wire sensor. Syock manifolds. 10 psi on fuel with a mr. Gasket fuel gauge 6" from the tie in to the TBI. Using 3/8 an lines, couldn't get to the frame to run hard lines I wanted. Seems constant while stationary revving engine, don't kno while driving. I was getting noise from the iac still after several attempts at adjustment. I went ahead and picked up a new one along with a tps nothing else I'll have a spare. Numbers seem "better" tps voltage before was not climbing above 1, now it will, albeit not by much. Will raise throttle. Now that I know where to look for my darn files I;ll have all kinds of good time to do some data logging! Intthe setup procedures it says you shoot for no less than 40, what would be allowable for my circumstance for my iac? Thanks for the newsbiggest problem I see is you are real Rich.
What motor do you have and what are the numbers on the injectors. See parts FAQ to determine.
What is the fuel pressure? Is it constant?
Your charging system looks good.
The idle screw could be increased a little to lower the iac at idle and get the tps closer to 0 at idle.
The chip looks very familiar. I think I May have the original somewhere in my files.
Bill USN-1
F.I. Moderator
My concern is you are so Rich that I think once you get everything set it will need a chip burned to correct the fuel.
The 40 counts on the iac is just a guideline to keep it from going to 0.
It can go lower but the motor needs to be completely warmed up and checked in your log after driving.
The 40 counts on the iac is just a guideline to keep it from going to 0.
It can go lower but the motor needs to be completely warmed up and checked in your log after driving.
I have more data, still very Rich. Thus very concerned. Have dropped my iac value down to 0 at idle, tps I believe is at .51 volts with a little more filing of the holes. Drove it to nm and back, put it through hell. Did well all things concerned. Seemed like the ECM "learned" somewhat while at highway speeds, driveability was better. Elevations ranged from 2000 fet to 11,500. I am convinced that it is overfueling, I don't think there are any more adjustments I can make to allow it to lean out. To rle out another possibility, I rerouted the return line so that it ties in to the overflow of the filler neck, to eliminate possibility of restriction when draining into the tank, no improvement. I will post data that I logged on the way down there. Thank you for the help. Btw iac is quiet now. Barley know the engine is running. Weird feeling.
Chris
Chris
Here's the log files, could only find the one blm... Will have more data in the morning. Thanks again. Looking for a definite consensus on what course of action I should take next. Thinking I need a new chip. Picked up a computer at the junkyard in didge city, 7747 out of an 88 gmc 5.7 w / 55lb injectors, ran verylean. Blms were in the 140s, curious. Wasn't expecting that. Back to my regular ECM with afi chip.
Bill USN-1
F.I. Moderator
Definately to Rich.
You will need another chip.
You could put the stock one you got in and log some blm. See if it really is lean.
If it's close you could bump the fuel pressure a little.
It all depends an which way you want to go.
What's strange is the original fuel table for your chip was leaner then the stock table but yours is Rich. So I don't know what table is in that one now.
You will need another chip.
You could put the stock one you got in and log some blm. See if it really is lean.
If it's close you could bump the fuel pressure a little.
It all depends an which way you want to go.
What's strange is the original fuel table for your chip was leaner then the stock table but yours is Rich. So I don't know what table is in that one now.
Bill USN-1
F.I. Moderator
Did you tell afi what your fuel pressure was?
Iirc you mentioned you were down to 10psi in an earlier post.
I don't think there is enough room to lower it enough to get the blm's close.
Iirc you mentioned you were down to 10psi in an earlier post.
I don't think there is enough room to lower it enough to get the blm's close.
Yes I did, they came back and decided not a good idea either. Suggested I try advancing the timing to 6-8 degrees. Ran to what I think is in the realm of 6-8. That is, no preignition, but advanced as far as I can go under the 10 Mark. Sent them data to review. Was late in the day, have not received a response, probably in the morning. Little to no change. Attached are my new files. No real improvement in driveability that I can tell. Numbers aren't good either.
Chris Pucci
Active member
Those numbers aren't good... How did the truck run before the efi?
With that little pressure and that Rich, I'm wondering if it isn't something non-efi cause you some trouble.
With that little pressure and that Rich, I'm wondering if it isn't something non-efi cause you some trouble.
Bill USN-1
F.I. Moderator
I considered the return but he states the inlet pressure is steady at 10psi. If the return was restricted the inlet pressure would increase.
The other part with direct control of fuel is map and temp.
Both are steady although the log and blm show that the full range of driving conditions are not covered so the adjustment based on the blm data will only be partial correction.
The other part with direct control of fuel is map and temp.
Both are steady although the log and blm show that the full range of driving conditions are not covered so the adjustment based on the blm data will only be partial correction.
Truck used to be setup with an edeflbrock 1406, squarebore to tquad adapter, stock guts, nothing fancy. Ran like a bat out of hell actually when the carb was in tune. I move around every few months for work, wyoming for awhile, texas, nebraska, Arizona, etc, so I wanted something I didn't have to tune for elevation. Efi. Truck was running great before the swap, only problem however is that when the truck would get up to operating temp, and air temp was at 90 plus, would start running like chit at low rpms. Convinced this was heat problems with the module inside the distributor along with an inop vac advance. When cool no problem. With your distributor, no problem at all.