MLS Install
- Thread starter MLS
- Start date
Monte Lauer
Active member
Bill USN-1
F.I. Moderator
Re: TBI wont build pressure.
You can buy the chips or could when I looked them up years ago, at GM. The netres chip was $14. Don't know what the bin chip was. By the time you buy both you could probably just hit a local yard and pick one up.
From my FAQ's.
You can buy the chips or could when I looked them up years ago, at GM. The netres chip was $14. Don't know what the bin chip was. By the time you buy both you could probably just hit a local yard and pick one up.
From my FAQ's.
Bill USN-1
F.I. Moderator
Re: TBI wont build pressure.
Depends if your auto or manual.
5.0 or 5.7
I use asdu for the 345 auto.
But now I have to ask what your other parts are?
Where did the injectors come from? They need to match the chip and engine also or more tuning will be needed.
Don't forget you also need the netres chip.
You need to replace both chips under the cover when switching from v6 to v8 or the other way.
Depends if your auto or manual.
5.0 or 5.7
I use asdu for the 345 auto.
But now I have to ask what your other parts are?
Where did the injectors come from? They need to match the chip and engine also or more tuning will be needed.
Don't forget you also need the netres chip.
You need to replace both chips under the cover when switching from v6 to v8 or the other way.
MLS
Member
Re: TBI wont build pressure.
The original 6299 ECM and harness I got together off a 92 suburban that I assumed was a 5.7l. The 7747 ECM I just tried, I got at the jy from a wrecked Chevy with no engine. I did not think to look and see if it had any info on engine or trans. What's next?
The original 6299 ECM and harness I got together off a 92 suburban that I assumed was a 5.7l. The 7747 ECM I just tried, I got at the jy from a wrecked Chevy with no engine. I did not think to look and see if it had any info on engine or trans. What's next?
Bill USN-1
F.I. Moderator
Re: TBI wont build pressure.
I already looked up the ecms and said the 6299 was from a 5.0l. The 7747 was from a 4.3l. So the questions above still apply. What are the other parts from.
Do you have 4.3/5.0/5.7 injectors?
You have to pick the parts to match the engine. You can't just grab a part from anything and expect it all to work together on your engine.
At least not without lots of chip tuning.
There are numbers on top of the injectors if it's not to rusty.
Could be 5206 or 5279 or something else.
I already looked up the ecms and said the 6299 was from a 5.0l. The 7747 was from a 4.3l. So the questions above still apply. What are the other parts from.
Do you have 4.3/5.0/5.7 injectors?
You have to pick the parts to match the engine. You can't just grab a part from anything and expect it all to work together on your engine.
At least not without lots of chip tuning.
There are numbers on top of the injectors if it's not to rusty.
Could be 5206 or 5279 or something else.
Craig
Active member
Re: TBI wont build pressure.
I figured I would post this here, so you would not have to find it. The numbers are on top on the injectors where the wires connect.
Color code black/white
engine 2.8l
flow lbs/hr @ 13psi 33
TBI bore 35mm
GM part # 5235430
color code yellow/blue
engine 4.3l
flow lbs/hr @ 13psi 45
TBI bore 43mm
GM part # 5235203
color code green/white
engine 5.0l
flow lbs/hr @ 13psi 40
TBI bore 43mm
GM part # 5235279
color code orange/black
engine 5.7l pu
flow lbs/hr @ 13psi 55
TBI bore 43mm
GM part # 5235206
color code yellow/brown
engine 5.7l copcar
flow lbs/hr @ 13psi 65
TBI bore 43mm
GM part # 17084327
color code blue/black
engine late bb pu
flow lbs/hr @ 13psi 80
TBI bore 51mm
GM part # 1708430
color code d red/d blue
engine early bb pu
flow lbs/hr @ 13psi 90
TBI bore 51mm
GM part # 5235231 "
I figured I would post this here, so you would not have to find it. The numbers are on top on the injectors where the wires connect.
Color code black/white
engine 2.8l
flow lbs/hr @ 13psi 33
TBI bore 35mm
GM part # 5235430
color code yellow/blue
engine 4.3l
flow lbs/hr @ 13psi 45
TBI bore 43mm
GM part # 5235203
color code green/white
engine 5.0l
flow lbs/hr @ 13psi 40
TBI bore 43mm
GM part # 5235279
color code orange/black
engine 5.7l pu
flow lbs/hr @ 13psi 55
TBI bore 43mm
GM part # 5235206
color code yellow/brown
engine 5.7l copcar
flow lbs/hr @ 13psi 65
TBI bore 43mm
GM part # 17084327
color code blue/black
engine late bb pu
flow lbs/hr @ 13psi 80
TBI bore 51mm
GM part # 1708430
color code d red/d blue
engine early bb pu
flow lbs/hr @ 13psi 90
TBI bore 51mm
GM part # 5235231 "
Chris Pucci
Active member
Re: TBI wont build pressure.
I have a whole bunch of chips in my garage -- so if you don't want to buy one off ebay -- I'll send you one. I think I have half the codes you listed above at least...
Just add it to the bill when you get your springs from me. Can't cost more than $1.50 to mail one to you...
I have a whole bunch of chips in my garage -- so if you don't want to buy one off ebay -- I'll send you one. I think I have half the codes you listed above at least...
Just add it to the bill when you get your springs from me. Can't cost more than $1.50 to mail one to you...
MLS
Member
Re: TBI wont build pressure.
That would be great if you could do that chris. Hopefully I can get those springs soon, just been tied up and can't seem to get to newberg. If you have the asdu chips I'll owe you big time!
Bill, I got the #'s off the injectors last night, 5235279. I know they are from a 305 but will these still work on my 345?
306 linden dr.
Tillamook 97141
That would be great if you could do that chris. Hopefully I can get those springs soon, just been tied up and can't seem to get to newberg. If you have the asdu chips I'll owe you big time!
Bill, I got the #'s off the injectors last night, 5235279. I know they are from a 305 but will these still work on my 345?
306 linden dr.
Tillamook 97141
Chris Pucci
Active member
Bill USN-1
F.I. Moderator
Re: TBI wont build pressure.
You can run them but will need to bump the fuel pressure to match.
You will be running a 5.7 chip that thinks it's driving 5.7 injectors.
So the fuel spray will be less then needed. Add to that the actual injector is smaller so the spray will be even less.
Here's the problem:
even if you bump the pressure to match the injector max volume of the 5.7 injector, the flow rate at each pulse will not be the same. So the blm's will still be out and will require tuning.
If you look at the attachment you will see that to adjust the pressure of a 5.0 inj to match the 5.7 (40-55lb/hr) the pressure needs to be increased to 25psi to maintain an 85% duty cycle on the injector.
You will also need to increase the bpw setting in the chip.
The 5.7 bpw is ~135 the 5.0 is 148. You need almost 200 according to the calculator. Now this is for max flow out of the injector without it having to run in the on position all the time. I will say that the calculator seems to be close for a 5.7 but the bpw calc for a 5.0 seems to be off. So only consider it a guideline.
So can you use them, sure. Will it be right, no.
The stock regulator can only be turned up to about 15psi.
That will take you from 40-43lb/hr. Not exactly the same as 55lb/hr.
You May be better off running a 5.0 chip for now and turning the fuel pressure up as needed.
You can run them but will need to bump the fuel pressure to match.
You will be running a 5.7 chip that thinks it's driving 5.7 injectors.
So the fuel spray will be less then needed. Add to that the actual injector is smaller so the spray will be even less.
Here's the problem:
even if you bump the pressure to match the injector max volume of the 5.7 injector, the flow rate at each pulse will not be the same. So the blm's will still be out and will require tuning.
If you look at the attachment you will see that to adjust the pressure of a 5.0 inj to match the 5.7 (40-55lb/hr) the pressure needs to be increased to 25psi to maintain an 85% duty cycle on the injector.
You will also need to increase the bpw setting in the chip.
The 5.7 bpw is ~135 the 5.0 is 148. You need almost 200 according to the calculator. Now this is for max flow out of the injector without it having to run in the on position all the time. I will say that the calculator seems to be close for a 5.7 but the bpw calc for a 5.0 seems to be off. So only consider it a guideline.
So can you use them, sure. Will it be right, no.
The stock regulator can only be turned up to about 15psi.
That will take you from 40-43lb/hr. Not exactly the same as 55lb/hr.
You May be better off running a 5.0 chip for now and turning the fuel pressure up as needed.
Attachments
Last edited:
Bill USN-1
F.I. Moderator
Re: TBI wont build pressure.
Keep in mind he needs both chips not just the bin.
Edit:
just checked my mail and got a package from a guy with a 5.7 bin and netres chip that is looking for a 4.3 set.
So if you don't have both then these 2 guys can swap sets and you could send him a 5.0 chip to try.
I can send mls these 2 and he can send his to the other guy.
Keep in mind he needs both chips not just the bin.
Edit:
just checked my mail and got a package from a guy with a 5.7 bin and netres chip that is looking for a 4.3 set.
So if you don't have both then these 2 guys can swap sets and you could send him a 5.0 chip to try.
I can send mls these 2 and he can send his to the other guy.
Last edited:
Chris Pucci
Active member
Re: TBI wont build pressure.
Are the little chips id'able? Somehow they have become seperated from the bigger chips....
Are the little chips id'able? Somehow they have become seperated from the bigger chips....
Bill USN-1
F.I. Moderator
Part # is in the parts required FAQ.
MLS
Member
Bill you lost me on the injector bpm. If you want to send the 5.7 chips I will put my v6 chips in the mail as soon as I get an address? Kind of stuck between you and chris right now. Either on works for me.
I'll keep my eye out for the right size injectors for now. I just want/ need to get this pile running soon. Thanks for all the help so far.
I'll keep my eye out for the right size injectors for now. I just want/ need to get this pile running soon. Thanks for all the help so far.
Chris Pucci
Active member
I have an asdu and a #16060837 chip ready to send out...
I also have a set of:
color code orange/black
engine 5.7l pu
flow lbs/hr @ 13psi 55
TBI bore 43mm
GM part # 5235206
if you want them you can 'buy' them too.... (unknown condition)
I also have a set of:
color code orange/black
engine 5.7l pu
flow lbs/hr @ 13psi 55
TBI bore 43mm
GM part # 5235206
if you want them you can 'buy' them too.... (unknown condition)
Last edited:
Chris Pucci
Active member
Last edited:
Bill USN-1
F.I. Moderator
If you plan to get 5.7 inj then use the 5.7 chip.
You guys work it out what you want to do and let me know so I know if I need to send out some chips.