Engine mods - EFI conversion
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Instructor
Joined: Apr 2016
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From: Stony Brook New York
Engine mods - EFI conversion
So I am want to go with an EFI conversion kit, but i am not sure if I can without having to do a whole lot of other mods as well.
I have an 81' and as mentioned and want to swap out the quadrajet for EFI and run true dual exhaust as well. I also don't know why my car has an O2 sensor when it's not an EFI model ...
If I do this Do I need to remove the ECU as will? and if I do that, how do I get the converter to lockup, replace the converter? That may not be worth doing the upgrade then, or make that a winter project sometime in the future ...
I have searched and read a bunch of post's on this but I am thoroughly confused as to the answer.
Thanks guys.
I have an 81' and as mentioned and want to swap out the quadrajet for EFI and run true dual exhaust as well. I also don't know why my car has an O2 sensor when it's not an EFI model ...
If I do this Do I need to remove the ECU as will? and if I do that, how do I get the converter to lockup, replace the converter? That may not be worth doing the upgrade then, or make that a winter project sometime in the future ...
I have searched and read a bunch of post's on this but I am thoroughly confused as to the answer.
Thanks guys.
Race Director
Joined: Apr 2003
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From: Tampa, Florida
Yes, you can do it without a whole lot of other mods, but then again, it depends what consider 'a whole lot' of mods.
There are basic throttle body style kits that go on like a carb and complete multi-port kits. Some people do it for a few hundred bucks with scavenged parts while others spend thousands.
There are basic throttle body style kits that go on like a carb and complete multi-port kits. Some people do it for a few hundred bucks with scavenged parts while others spend thousands.
Thread Starter
Instructor
Joined: Apr 2016
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From: Stony Brook New York
I guess I should have qualified everything ... Sorry.
I am considering a basic throttle body EFI system, like the Holley one coming out later this year. But that would cause the ECU to not communicate with the Quadrajet and cause a check engine light. I can get an O2 bypass module, but still can't figure out the carb bypass route.
I don't want to remove the ECU if I can help it. I have a TH350 tranny that is solid and I am not ready to replace the torque converter just yet.
I am considering a basic throttle body EFI system, like the Holley one coming out later this year. But that would cause the ECU to not communicate with the Quadrajet and cause a check engine light. I can get an O2 bypass module, but still can't figure out the carb bypass route.
I don't want to remove the ECU if I can help it. I have a TH350 tranny that is solid and I am not ready to replace the torque converter just yet.
Last edited by Skybolt; Apr 18, 2016 at 02:36 PM.
Drifting
Joined: Jun 2012
Posts: 1,990
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From: Port St. Lucie Fl
the new efi will replace your carb, o2, and ecu. Did th350 come with a lock up convertor? either way you find the wiring harness for it and either wire it to a toggle switch or buy the b&m vacuum kit and adjust it to your liking.
Last edited by Kacyc3; Apr 19, 2016 at 12:09 PM.
Thread Starter
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From: Stony Brook New York
I was looking at the B&M kit on summit. looks like a nice glove box Item if I do need it? If the lockup is electronic I can keep the ECU and dummy up the O2 sensor. I need to look into this. Thanks for your post.
Last edited by Skybolt; Apr 19, 2016 at 12:45 PM.
Thread Starter
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From: Stony Brook New York
So the spec sheets for an 81' state "TORQUE CONVERTER CLUTCH, 2ND & 3RD GEAR LOCK-UP" but does not state electric or manual?
Does anyone know what type is used? I am guessing manual by cable? is that right?
Sorry for asking dumb questions, I have never played around with an automatic, so I don't know much about them.
Does anyone know what type is used? I am guessing manual by cable? is that right?
Sorry for asking dumb questions, I have never played around with an automatic, so I don't know much about them.
Last edited by Skybolt; Apr 19, 2016 at 01:20 PM.
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From: Stony Brook New York
So I found this in a service manual "In 1980 (except California models), an electrically controlled locking torque convertor was introduced to improve fuel economy. All 1981-82 models have this feature."
So I am going out on a limb here and guessing that the lock up is controlled by a modulator and not the ECU, since 80' doesn't have an ECU or do they?
So I am going out on a limb here and guessing that the lock up is controlled by a modulator and not the ECU, since 80' doesn't have an ECU or do they?
Last edited by Skybolt; Apr 19, 2016 at 01:54 PM.
Thread Starter
Instructor
Joined: Apr 2016
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From: Stony Brook New York
on 1980's cars it is controlled by a few engine factors, in 1981 it is solely the ECU and a controller is needed to achieve lockup at speed.
So I can ditch all of the smog and ECU crap and go with a new HEI dist. and EFI throttle body unit if I use the B&M controller.
Well thanks to google this has been a learning experience today! I hope everyone who reads this has a good laugh, I know I sure would ...
So I can ditch all of the smog and ECU crap and go with a new HEI dist. and EFI throttle body unit if I use the B&M controller.
Well thanks to google this has been a learning experience today! I hope everyone who reads this has a good laugh, I know I sure would ...
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From: Stony Brook New York
Thanks, I didn't realize that there was rich/lean valve in the mix. I guess I chose poorly with an 81', I didn't realize that this was the first year with an ECM, I thought only 82' was. I still love the car though and very happy I got her.