Ok, so my build is finally getting closer and closer to being done, and while I'm waiting for more parts to come in, I've been looking at everything electrical. I'm pretty sure I have a few problems.

I am building a 355 Vortec TPI LT4 Hotcam full roller engine to be paired with a ProBuilt Street and Strip 700-R4. I decided to switch to MAF after having tons of problems with MAP in the V6, so I bought a standalone wiring harness for a 165 and got a 165 ECM to make it all work. I have all the sensors that I need to run it save for the VSS, knock and O2.

Another reason I decided to switch to MAF was because it would be much easier to tune with the much larger cam profile over stock that the LT4 hotcam was going to give me. But now that its all coming closer to being done, I've started to realize that I'm going to have problems putting it all together and having all the information that the dash displays, sent to the dash.

So what can I do besides getting a new harness for a 7730 and finding the proper PROM to run the V8 and replacing my V6 prom? I'm pretty much trying to interface 86-89 engine wiring with 90-92 vehicle wiring...

And if it comes back to a 7730, how would I go about tuning it to make it work correctly for the obvious valvetrain mods? Thanks guys.

 

Buy a dokota digital sgi-5 to convert your magnetic pulse 4k ppm signal to a optical 2k ppm for the 165 and 4k ppm for the speedometer.

 

I don't want a digital dash, I want to use the stock dash. And considering that I already have a stock dash set up for a V8, I don't want to make the change. I'm thinking my only option is to ditch the 165 and go with the 7730 and just find the right PROM, in which case, I have a perfect 165 ECM and fuel injection connection harness for sale....

It would be awesome to run the 165 though because of the obvious benefits of tuning with the different valvetrain.

 

Than what is your question ? I gave you the solution of what to buy.

http://www.summitracing.com/parts/dak-sgi-5

 

To make the 165 wiring work with the stock vehicle wiring and be able to use my stock dash. The Dakota Digitals are just god awfully ugly IMO...

I won't go that route, thats not a solution to my problem.

EDIT....I thought you were telling me to get a Dakota Digital Dash.

Alright then..this will convert me over to make my speedometer work right, but the connectors that I would be bypassing in my service manual seem to cover more than just me losing my speedometer.

 

You don't need to mount the box in a visible location mount it next to the ecm.

 

Alright so I guess my real problems are the C100 and the C207 connector. I'm trying to find all the pinouts and see whats different.

 

http://www.austinthirdgen.org/index.php?pid=19

 

The ECM and the gauges do not communicate at all. The senders for the gauges are independent of the ECM. The only exception is if the speedo is an electric speedo and not mechanical, which is what I believe the later 3rd gens had that used the '7730. So then this really comes down to what the transmission you are using has to send vehicle speed information to the cluster or ECM.

 

This is becoming more of a wiring question now, but what can I do about the C100 and the C207 connectors? I cant find a 7730 V8 TPI harness anywhere locally, or a 350 computer to run it.

 

Since you don't like the idea of the sgi-5 you can find the 730 and sd harnesses in the classified section but the expensive part of the swap will be a real sd 350 memcal.