Slant Six Forum
https://mail.slantsix.org/forum/

Turbo engines and distributors
https://mail.slantsix.org/forum/viewtopic.php?t=3595		 Page 1 of 1
Author:  Matt Cramer [ Fri May 10, 2002 7:57 pm ]
Post subject:  Turbo engines and distributors
For all you turbo slant six owners out there, how did you deal with getting the spark curve dialed in? Is there a vacuum advance with a pressure retard out there for the /6? Or is such a thing unnecessary? besides recurving, how much work do you have to put into modifyin the distributor?
Author:  Doctor Dodge (Doug Dutra) [ Sat May 11, 2002 8:00 pm ]
Post subject:  Re: Turbo engines and distributors
Quote:
: For all you turbo slant six owners out there,
: how did you deal with getting the spark
: curve dialed in? Is there a vacuum advance
: with a pressure retard out there for the /6?
: Or is such a thing unnecessary? besides
: recurving, how much work do you have to put
: into modifyin the distributor?


Wow,
You just hit the reason I do not run a turbo SL6 as an "everyday car", I could never get the advance curve "mapped-out" right.
Best I ever got was a mechanical advance system and an MSD retard, no vacuum advance.
In concept you may be able to find a place "up-stream" of the turbo and pick-up some kind of vacuum advance signel there.
Thruth is that it is best to go to an EFI set-up with the sensors and a computer "map" to follow the needed turbo curve. This is pretty high tech stuff but the technolgy is here, you just need to learn it!
DD
Author:  Matt Cramer [ Sun May 12, 2002 11:36 am ]
Post subject:  Re: Turbo engines and distributors
That difficult, eh? Guess I might need to get an MSD6 Boost Timing Master, or maybe even one of the Electromotive crank-triggered ignitions. I'd hoped I could get it to retard the timing mechanically.
Author:  Charlie Schmid [ Sun May 12, 2002 12:16 pm ]
Post subject:  Re: Turbo engines and distributors
MSD has two different boost timing masters. Part number 8962, has both pressure retard, and vacuum advance. I have one, but have not used it yet.
Charrlie_S
Quote:
:
: That difficult, eh? Guess I might need to get
: an MSD6 Boost Timing Master, or maybe even
: one of the Electromotive crank-triggered
: ignitions. I'd hoped I could get it to
: retard the timing mechanically.



flturbo6@aol.com
Author:  Bob D [ Sun May 12, 2002 7:55 pm ]
Post subject:  Re: Turbo engines, ECM, Knock Det. and distributor
Quote:
: For all you turbo slant six owners out there,
: how did you deal with getting the spark
: curve dialed in? Is there a vacuum advance
: with a pressure retard out there for the /6?
: Or is such a thing unnecessary? besides
: recurving, how much work do you have to put
: into modifyin the distributor?


Matt,
You should be able to use an EFI ECM and knock detector without the fuel injection to control just your timing. You would need the GM ECM, Electronic Spark Control (ESC) module, knock detector, and a 7-pin GM ignition module. <A HREF="http://slantsix.org/articles/dibiase_ef ... chm.jpg</A>). Of course the idea here is that the ignition would be retarded whenever any knock is detected. To use this approach you would have to use a SL6 electronic distributor with the vacuum advance and centrifugal advance disabled.

Bob D


BBobbias@aol.com
Author:  Ray [ Sun May 26, 2002 11:19 pm ]
Post subject:  Re: Turbo engines and distributors
Quote:
: Wow,
: You just hit the reason I do not run a turbo
: SL6 as an "everyday car", I could
: never get the advance curve
: "mapped-out" right.
: Best I ever got was a mechanical advance system
: and an MSD retard, no vacuum advance.
: In concept you may be able to find a place
: "up-stream" of the turbo and
: pick-up some kind of vacuum advance signel
: there.
: Thruth is that it is best to go to an EFI
: set-up with the sensors and a computer
: "map" to follow the needed turbo
: curve. This is pretty high tech stuff but
: the technolgy is here, you just need to
: learn it!
: DD

I am not even sure of this, but could you not drill a hole on the back side of the vacumn advance module. run a line from the boost side of the turbo to it to provide a make shift "BOOST REFERENCED" advance? Then just work in the mechanical side and limit the total. I may be to far off track, just thinkin! :)

tjszubart@Excite.com
Author:  GTS225 [ Mon May 27, 2002 10:55 am ]
Post subject:  Re: Turbo engines and distributors
Quote:
: I am not even sure of this, but could you not
: drill a hole on the back side of the vacumn
: advance module, run a line from the boost
: side of the turbo to it to provide a make
: shift "BOOST REFERENCED" advance?
: Then just work in the mechanical side and
: limit the total.

**************************************************
Hmmmmm, now THIS sounds like a decent idea. Seems to me that if it works for a fuel pump, why not for a vac advance. They are both vac diaphrams, just that one is mechanically motivated to move a liquid, while the other is vac'm motivated to move a mech'l linkage.

It should work when the vac advance is plugged into the standard ported vac on a carb or throttle body. It would then "see" the pressure differences between boost pressure and venturi pressure

Roger

GTS225@aol.com
Page 1 of 1 All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/