Can anyone inform me of the logistics of putting a power chip into the 302 of an 88 full size Bronco? It has SD EFI on a complete rebuild but I have been told by the shop that had to send my ecm out for rebuild after being struck by lightning that it's a California Bronco and that you can't install upgrades or aftermarket chips or ecm units for those Bronco's.

Can I just install the power chip anyway? Can I just replace the ecm with a non California unit and then add a power chip? Does anyone know if the California ecm's govern down these engines because it's brand new but I'm not getting any more power out of it?

I would spend the time looking for these answers in the forums but I don't have enough time left in my life to read all 7 million posts to find what I am looking for.

Any help or pointing in the right direction would be greatly appreciated.

 

For the '88 you should be able to use any chip module made for a EEC-VI computer. Our chips can be used for EEC-VI and EEC-V ECM's as long as you have the tuning software to support the vehicle. It being Cali I am not 100% certain on tuning gains. It being that far back in years I am not sure with out a Definition to tell what there is for adjustability in the tuning. You'd need to start there.

Have you checked the Bronco forum to see what others have done?

 

Sorry Jody.. but chips are a complete waste of money on this vintage truck, the only thing they can do is advance the timing and you can do that for free by simply turning the distributor.

If you got your engine rebuilt to '88 spec and you still have the stock exhaust on it that is your problem, the exhaust is a cork but even worst the stock cam is rediculously small and severly limits engine output. The solution is to install a better cam(Comp Cams 31-255-5) and replace as much of the stock exhaust as you can get away with, there are CARB legal headers and replacement Y pipes available for these trucks, check out Summitracing for your options. You can use a non california EEC in this truck, there are many different calibration codes but overall there's not enough difference in any of them that you would be able to tell from the drivers seat. I'd suggest you source a used or parts store replacement for your EEC instead of having it "rebuilt".. likely to be cheaper and quicker.

 

Sorry Conaksi, but this is Diane. I don't know what or if any tuining would be effective. I didn't recommend a chip, but we do have the available harware for the ECM to accomodate his needs if he desires to persue finding someone to tune for it. I have to agree there was probably limited parameters in the PCM to be able to make effect adjustments.

 

Thanks for the input guys and gals. The engine was rebuilt with an Engine Pro MC1734 cam with specs to keep it playing nice with the Speed Density fuel injection. I have a feeling that fuel injection system is part of the problem.

The exhaust is stock except for a set of shorty headers from LMC. I installed those to eliminate the problem with the passenger side exhaust manifold cracking. Other than that, it's all stock. What would you recomend for upgrades??

For the purpose of advancing the timing, how much would you recomend and will the computer just compensate for the adjustment anyway?

 

The stock cam is THE bottleneck in this vintage motor, the Comp cams 31-255-5 has been swapped in by quite a few here on this forum and they report surprising power increases and no SD EFI related issues.
The stock cats are also quite restrictive, several companies inclusing Bassini and Magnaflow are producing direct replacement Y pipes with and without cat converters that flow a ton better.
Base timing can usually be bumped to between 12-14deg(from 10) before detonation becomes audible on 87 octane, and with a high output coil and better wires the plugs can be gapped wider and timing further bumped to 16deg or more depending upon the grade of fuel used.

 

Well, it's too late to change the cam now. I'll just see what I can get out of the timing and exhaust.

 

If you don't want to go deep inside the motor after the cam you can still get some more valve lift by adding 1.7 rockers, these won't produce the gains a cam would but they will certainly help and you only need to remove the upper plenum and valve covers to install them.

 

I advanced the timing and got quite a bit of boost from it. I am pretty happy with that so far but I am having a problem with it stalling when from idle, I give it a bit of throttle to get the Bronco moving and then let off. This only happens after it warms up. I haven't run the diagnostics yet but feel either a vacuum leak somewhere or a bad sensor that I haven't changed during the rebuild. Does anyone think that the O2 sensor might cause this?

 

seems like you got the timing a little out of whack when you advanced it