Esc

[TurbOlds]

Im about to swap an 81 3.8 turbo int my 81 cutlass in place of the boat anchor 267. im getting the engine from a parts car i bought, an 83 cutlass. some where along the way, probably when the engine was swapped the first time, the ESC disappeared. i was wondering if i should get one from a 4.1 equipped car at the wreckers or buy the msd BTM. what would be involved in wiring the ESC into my cutlass which originally did not have an ESC? i just want something to retard the timing when under boost or to sense detonation and protect the engine. thanks, Adam

 

[b4black]

Is the '81 engine controlled by an ECM? (If so, the carb will have electronic controls and the distibutor won't have a vacuum advance cannister.) Is there a casting number on the intake?

An '81 engine could be a US/Federal with ECM or a export, without an ECM. Each uses a very different ESC.

 

[b4black]

Maybe more important is whether or not you plan to use an ECM with the motor in the '81 Cutlass.


Also, '81 was the only year for the "Normally Open" wastegate. When not running, the WG is pushed open by the actuator spring (instead of being pulled closed). Is your like this? You may want to consider changeing this if it is.

 

[TurbOlds]

no, the engine is not ecm controlled, no wires to the carb and vac adv distributer. the wastegate is normally open, why is the normally closed one better? should i buy a wastegate for an 80 or 82? i'll post the casting # from the intake when i get home tonight. Thanks, Adam

 

[b4black]

Non-ECM's motors are much easier to transplant.


The non-ECM ESC (labeled TURBO CONTROL CENTER) is basically stand alone unit. On 1978/79's it was placed on the fan shroud and the senor was on the intake's thermostat housing. In 1980, the intake was made from aluminum and the sensor was moved to the back of the block. The controller was put under the dash.

You will need to get a Turbo Control Center, a sensor (still avaliable new for about $60 ), a relay (likely still available) and the distributor's wiring harness (maybe still there?, four pin round plug I think)

Here is a 1978/79 ESC wiring diagram:
http://home.flash.net/~rjgeorge/images/wire78esc.jpg

I don't think that 4.1's used ESC until the got ECM's, but maybe export 4.1's did.


The normally open wastegate starts opening whenever engine vacuum drops. The normally closed WG stays shut longer which gives faster spool-up (less lag).

The '81 normally open WG was for economy. In 1982, they went back to normally closed for performance. Any elbow from a 1978/80 or 82/83 RWD Turbo will work. You'll need the elbow and actuator.

 

[b4black]

Actually, while your chaning the turbo elbow, you might as well change the turbine to a 82/83 unit. It is a 0.63 A/R compared to the 19788/81's 0.85. The smaller housing helps increase spool up as well.


And a in-line releif valve between the compressor and actuator will help to.
http://www.turbobuick.com/forums/showthread.php?s=&threadid=10760

 

[TurbOlds]

thanks for the help, but i have a few more questions. what does the sensor look like? on the back of the block, at the top, there is something. its the same place an oil pressure sending unit would be on a small block chevy. im just hoping the sensor is still there are th TCC units still available, or do i have to try and find a used one? if i decided to just go with the MSD BTM, would there be any problems? i know the BTM doesnt sense detonation so i wouldnt know if it was knocking lightly. thanks, Adam

 

[TurbOlds]

do you have to change the whole turbo as a unit, or just the housing to a 82/83?

 

[b4black]

Here's a top view of a knock sensor. It's the thing in the lower center, just above the coolant outlet ('79 iron intake). http://home.flash.net/~rjgeorge/images/intake79.jpg On a '80/83 motor, it is on the block, behind the intake, directly under the EGR valve. (It's been a long time since I have looked at a SBChevy )


Turbo Control Center are long discontinued. Trouble with used one's are knowing whether they are good or not.

I want to try a MSD BTM, but in addition, not instead of ESC.


You can change the just elbow and turbine housing, but the complete turbo has to be removed from the enigne first. All 1979/83 turbos use the same center section.

 

[Peter]

Other Options

If all else fails, try this;

http://petesbuick.topcities.com

 

[TurbOlds]

Peter, i think ill go with your suggestion. one question though, I dont have a boost indicating light to turn the vacuum switch on. im guessing ill have to use a pressure switch of some sort to turn the vacuum switch on to get the carb to go full rich. du you have any suggestions as how to go about this? Also, was the parts list for the circuit with the ESC or without? Did you design this yourself? if you did, damn your smart! Thanks, Adam

 

[Peter]

You will need a Hobbs switch {same as the boost switches usually fitted} set to zero psi {atmospheric pressure} for the non electronic PECV set up, and wire it as shown. Some Hobbs switches are adjustable and some fixed.

The circuit and parts list for the combination PECV/IGNITION RETARD are the same with or without the ESC. The difference is how it gets wired into the car system. If you compare the "with ESC" and "without ESC" wiring diagrams you will see the difference.

Hope some of this stuff gets you back on the road.