N/A 4.3 Chip/Tune

Meano

Meano

New member
I have recently done the Edelbrock 2114 and 98 Vortec head swap. Everything is back together and the car is running, but just off. Timing is bouncing around, and it sounds as if it's trying to adjust itself. I don't know how I overlooked it before, but I'm convinced the stock computer is the issue. I've read good things about the turbotweak chip but for the time being I'm N/A with plans of boost in the near future and I'm not sure if this is compatible. I've called all the local peformance shops and no one messes with chips anymore. Could someone help point me in the right direction? I'm anxious to get this thing back on the road!

Thanks
 
Meano

Meano

New member
Re: N/A 4.3 Chip/Tune

As far as I can tell it is the stock ECM..

I was surprised to find out my "factory" El Camino had 94 heads on it, meaning it was probably a new motor, but I'm not sure if the ECM was ever replaced. Not sure if there is much of a difference between 87 & 94 TBI ECMs either way.
 
Meano

Meano

New member
Re: N/A 4.3 Chip/Tune

12secondSY said:
If it ran fine before you're probably a tooth off in the distributor.
Click to expand...

The timing is set to 0 but bounces around between 0-4 while it's running. Local shop seems to think its because the EGR delete and new fuel curve.
 
Meano

Meano

New member
Re: N/A 4.3 Chip/Tune

Stock cam..

It was a completely stock 4.3 TBI. Threw on the 2114 with a TBI adapter and 98 heads. Those were the only changes I made.
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: N/A 4.3 Chip/Tune

SyTy have a different ECM than rest of the S-Series. (SyTy use a 749 ECM that was in the turbo Sunbirds).

I would guess using the 2114 intake that you changed injectors. The 98 heads flow probably 40% more than the stock LB4 heads. If the TBI use MAP sensor to the fuel the engine it will not know how to compensate for the additional air flow. (20" of HG with Vortec heads is going to be a to more air flow than 20" of Hg with LB4 heads.) It wouldn't surprise me it ran like crap.

I don't know what the TBI owners are using for custom fueling. I am not sure if their is support of the TBI ECM. I would find out what ECM you have (last three numbers of the part number) and look on thirdgen.org in the DIY prom forum.

I know the SyTy 749 ECM can be used for DIY custom tuning. I know some have used the new 411 ECM that will have support of typical tuners.
 
Meano

Meano

New member
Re: N/A 4.3 Chip/Tune

I used the stock injectors, which I'm going to assume is the issue. I knew the heads flowed better, I just didnt think it would starve at idle. I'm going to grab larger injectors and put them in this weekend and see how it runs.

I appreciate the help, after looking at the ECM I should be able to figure something out.
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: N/A 4.3 Chip/Tune

Changing injectors is a stab in the dark. Even if it happens to fixes the idle, it probably won't work across the rpm range.
 
12secondSY

12secondSY

Syty Killer :(
Re: N/A 4.3 Chip/Tune

Meano said:
The timing is set to 0 but bounces around between 0-4 while it's running. Local shop seems to think its because the EGR delete and new fuel curve.
Click to expand...

I have no experience with TBI on anything other than stock so dgoodhue probably knows more about it. I've had times where it all looked good pulled the distributor and reset it just to verify and fixed my problem. Mostly on 4.3L engines too. I don't know why but I've probably done it 5 out of 10 times lol. Never on a V8.

Maybe cover the TB to choke it and see if it smooths out. Or there's always carburetors :)
 
Meano

Meano

New member
Re: N/A 4.3 Chip/Tune

Bigger injectors were coming either way, so now I have an excuse! I'll mess with the distributor a little more tonight and see how she likes it. I was close to saying F it and putting on a carb but it'll only make things harder when I turbo it.

The EBL flash that TeeTopZ linked actually looks like a winner. Going to call and pick their brain before I pull the trigger. Again, thanks for the help!
 
TittyTy

TittyTy

Donating Member
Re: N/A 4.3 Chip/Tune

I used Tbichips.com when I swapped the 2114, 03 vortec heads, and cam on my 88 C1500 Silverado 4.3. Worked great. Although I already had a 670cfm T.B. from holley on there w/bigger injectors, I still had to swap the fuel pump to keep up with demand from the new set up
 
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