L83 1984 Help
Le Mans Master
Joined: May 2006
Posts: 7,708
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From: indy indiana
I have a set of vortec heads on my engine(1970 ) in the garage. I had to buy a special manifold for a carb and about to but one for the TPI on my 86.This is a decent read about vortec heads , http://www.chevyhiperformance.com/howto/97458/
be aware that 87 and later engines used a roller cam but real vortec headfs diddent appear until 96. Many confuse centerbolt heads with vortecs. Apples and oranges. Scroggins/Dickey , down texas way have a lot of hotrod stuff for the vortecs as well as other chevy engines. They claim there vortec manifold for the TPI adds 50 hp just by itself.
http://www.gmhightechperformance.com...ine/0209gmhtp_
https://sdparts.com/details/scoggin-...-center/sd3816
be aware that 87 and later engines used a roller cam but real vortec headfs diddent appear until 96. Many confuse centerbolt heads with vortecs. Apples and oranges. Scroggins/Dickey , down texas way have a lot of hotrod stuff for the vortecs as well as other chevy engines. They claim there vortec manifold for the TPI adds 50 hp just by itself.
http://www.gmhightechperformance.com...ine/0209gmhtp_
https://sdparts.com/details/scoggin-...-center/sd3816
Last edited by ghoastrider1; Dec 21, 2013 at 09:44 PM.
Racer
Joined: Aug 2013
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I put the vortec engine in my 98 chevy p.u. together from spare parts, still runs great for 8 years now. I always wondered what it would be like to have it in my 84 vette. As long as you can get all the wiring and related along with the engine, the biggest part will be the wiring and making sure the induction clears the hood.
Advanced
Joined: Aug 2007
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If I were you, and you want to go to a vortec engine, I would get an ecu and the wiring harness for that engine. Don't bother with trying to re-use the 84 ecu and wiring. The connection between the harness and ecu on the 84 is unique, my toaster has more brain power than the 84 ecu, and the insulation on the wires are probably like the toast crumbs on the bottom of my toaster, by now. 
The only thing you will lose with a different ecu is the current/average mpg display. The speedometer would not be affected at all. The Tach probably not. The thing to make sure of, is all the wiring connections. This is where it gets tricky. You need to make sure all the connections are correct for it to work correctly. On the 84, the speed input into the ecu come from the dash, not the transmission vss. With the "new" ecu, what kind of signal is it looking for (rhetorical question)? Is it the same as the 84 (rhetorical question)? 
Good luck!
The only thing you will lose with a different ecu is the current/average mpg display. The speedometer would not be affected at all. The Tach probably not. The thing to make sure of, is all the wiring connections. This is where it gets tricky. You need to make sure all the connections are correct for it to work correctly. On the 84, the speed input into the ecu come from the dash, not the transmission vss. With the "new" ecu, what kind of signal is it looking for (rhetorical question)? Is it the same as the 84 (rhetorical question)? Good luck!
Racer
Joined: Aug 2013
Posts: 301
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Are you asking how to make it work with a different ecm? If so, at worst you would have to get a signal converter to put the right signal to whatever ecm you use. Right now the vss signal runs to the speedo first, at 4000 pulses per mile, then gets sent to your ecm by the cluster at 2000 pulses per mile. I think (not sure) that the vortec ecm will be looking for a 4000 pulse per mile signal. If that is the case, just tie into the vss wires going to the cluster to run the signal to the vortec ecm instead of using the signal from the cluster. After that you may need to get the ecm reprogrammed with your final drive gear ratio. The vortec ecm normally controls a 4L60E transmission (if automatic), but yours is a 700R4 (similar without the electric shift solenoids) Maybe that can be programmed as well.
Last edited by nobodycls; Dec 22, 2013 at 03:25 PM.
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Thread Starter
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Are you asking how to make it work with a different ecm? If so, at worst you would have to get a signal converter to put the right signal to whatever ecm you use. Right now the vss signal runs to the speedo first, at 4000 pulses per mile, then gets sent to your ecm by the cluster at 2000 pulses per mile. I think (not sure) that the vortec ecm will be looking for a 4000 pulse per mile signal. If that is the case, just tie into the vss wires going to the cluster to run the signal to the vortec ecm instead of using the signal from the cluster. After that you may need to get the ecm reprogrammed with your final drive gear ratio. The vortec ecm normally controls a 4L60E transmission (if automatic), but yours is a 700R4 (similar without the electric shift solenoids) Maybe that can be programmed as well.
Racer
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Thread Starter
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Joined: Oct 2013
Posts: 98
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onto another issue, it idles correctly now and seems to burn less oil
but the brake pedal is hard and has very little travel and the brakes dont stop very well
i dont see any vacuum leaks and while the brake fluid is a little dirty, it isnt low and i will change it later, but i dont think that would cause this
what might be the problem?
but the brake pedal is hard and has very little travel and the brakes dont stop very well
i dont see any vacuum leaks and while the brake fluid is a little dirty, it isnt low and i will change it later, but i dont think that would cause this
what might be the problem?
Racer
Joined: Aug 2013
Posts: 301
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onto another issue, it idles correctly now and seems to burn less oil
but the brake pedal is hard and has very little travel and the brakes dont stop very well
i dont see any vacuum leaks and while the brake fluid is a little dirty, it isnt low and i will change it later, but i dont think that would cause this
what might be the problem?
but the brake pedal is hard and has very little travel and the brakes dont stop very well
i dont see any vacuum leaks and while the brake fluid is a little dirty, it isnt low and i will change it later, but i dont think that would cause this
what might be the problem?
Thread Starter
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Joined: Oct 2013
Posts: 98
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no vacuum gauge but what makes me think the brake booster is dead is the fact that it hisses, and i cannot press the brake pedal to the floor
going to just replace it, seems to be a 10" unit, but i am wondering if only other 10" units will fit or if a 9" or 11" booster would work as well
going to just replace it, seems to be a 10" unit, but i am wondering if only other 10" units will fit or if a 9" or 11" booster would work as well