TBI Issues, #8 Cylinder Dead

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bucket

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My '85 and '86 TPI motors have the large cap stock and I've often thought about converting to the small cap for better firewall clearance. I guess I won't be doing that.
 

Jims86

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My '85 and '86 TPI motors have the large cap stock and I've often thought about converting to the small cap for better firewall clearance. I guess I won't be doing that.

You can do it on your 86, and just change the PROM. They used that ECM till 89.
As far as the 85, that has a real slow ECM, and If I were you, I would convert it to the later ECM if you want to keep MAF, or even the 90-92 speed density ECM.
 
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bucket

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You can do it on your 86, and just change the PROM. They used that ECM till 89.
As far as the 85, that has a real slow ECM, and If I wer you, I would convert it to the later ECM if you want to keep MAF, or even the 90-92 speed density ECM.

I've already had Brian at TBI Chips cange the 86's prom a few times and I need to do something again. I guess then would be the time to do it huh? I'm thinking I'm going to shitcan the whole MAF setup though and go with SD. That damn MAF sensor has been giving me drivabilty issues for almost 10 years. I could tell you the whole story, but it would be like 5 HRPC stories all put together. I'm sick of the intermittent problems though, it's bad enough now that the car can't even be driven when it acts up. It can go for a week without screwing up, but sometimes it will screw up 5 times in 2 miles.
 

89Suburban

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Damn I love this discussion!! :popcorn:
 

Jims86

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I've already had Brian at TBI Chips cange the 86's prom a few times and I need to do something again. I guess then would be the time to do it huh? I'm thinking I'm going to shitcan the whole MAF setup though and go with SD. That damn MAF sensor has been giving me drivabilty issues for almost 10 years. I could tell you the whole story, but it would be like 5 HRPC stories all put together. I'm sick of the intermittent problems though, it's bad enough now that the car can't even be driven when it acts up. It can go for a week without screwing up, but sometimes it will screw up 5 times in 2 miles.

Yup, I really like the 7730 ecm from the 90-92. Its faster, but it wont respond as well as the MAF system will to big changes, like cams or heads. Small price to pay IMO.
The only thing I had a problem with,was the rough Idle....which I know now was due to the big Dizzy.
Kind of a bummer.
 

Jims86

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Damn I love this discussion!! :popcorn:

There is a lot to be learned. I did my first EFI conversion when I was 16....still learning new stuff all the time!
 

Guardian

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I still have the harness and ecm for mine, but have not installed it yet. I need to do some more research before I pull the carb and go to the TPI.
 

Jims86

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I still have the harness and ecm for mine, but have not installed it yet. I need to do some more research before I pull the carb and go to the TPI.

You have any pics of your TPI....Post em up...Make this a real EFI Post!
 

Jims86

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I still have the harness and ecm for mine, but have not installed it yet. I need to do some more research before I pull the carb and go to the TPI.

You have any pics of your TPI....Post em up...Make this a real EFI Post!Hers my old one:(
You must be registered for see images attach
 

Guardian

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Only pictures are of it not in the truck. Couldn't get the bugs worked out on the dyno before I went back to work so am currently running the same engine on a carb. And yes, all I did was change the intakes. I have people ask all the time if it still has the EFI cam in it.
 

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