Changing 4+3 Control Tables?
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
Changing 4+3 Control Tables?
My apologies if this has been answered previously, I did not see it in my searches.
I have an 86 Corvette with 4+3 (http://www.5speeds.com/43table.htm) and custom chip. Currently the only change made to the chip is that the OD does not automatically turn on as with stock.
However, I really would like to be able to control OD on/off with the thumb switch completely (aka set kickdown to TPS voltage of 7 volts or something that would never be acheived.)
I've heard that you can do some re-wiring in such a way that the button on the shifter controls the OD in an on/off manner but is it possible to do this on the chip?
TIA
Also, are there corvette specific xdf, ads, bin etc files that have definitions for the 4+3 that other manual transmission/variations might not show? If so, where can I get them.
Thanks!
I have an 86 Corvette with 4+3 (http://www.5speeds.com/43table.htm) and custom chip. Currently the only change made to the chip is that the OD does not automatically turn on as with stock.
However, I really would like to be able to control OD on/off with the thumb switch completely (aka set kickdown to TPS voltage of 7 volts or something that would never be acheived.)
I've heard that you can do some re-wiring in such a way that the button on the shifter controls the OD in an on/off manner but is it possible to do this on the chip?
TIA
Also, are there corvette specific xdf, ads, bin etc files that have definitions for the 4+3 that other manual transmission/variations might not show? If so, where can I get them.
Thanks!
Burning Brakes
Joined: Aug 2006
Posts: 1,061
Likes: 99
From: Seattle WA
No re-wiring necessary. OD is controlled in the TCC lockup MPH vs. TPS tables and the TCC Unlock/prevent OD engage speed constant. Just set the lock TPS to 0% for each MPH and set the prevent OD engage constant to 255 mph, and you'll have manual control with the button.
For an '86, you need the "32.xdf" definition file to interpret the calibration data on the chip. You can get it at moates.net (file upload and download area) or tunerpro.net.
For an '86, you need the "32.xdf" definition file to interpret the calibration data on the chip. You can get it at moates.net (file upload and download area) or tunerpro.net.
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
Awesome! Thanks, that is much better than cutting/splicing wires! I grabbed the 32.xdf off of moates too.
Nice Callaway, I went to UW for my BS. I miss Seattle, it is great up there.
Nice Callaway, I went to UW for my BS. I miss Seattle, it is great up there.
Burning Brakes
Joined: Aug 2006
Posts: 1,061
Likes: 99
From: Seattle WA
You're probably not missing Seattle so much now that summer's over! I came from DC, and the winters here are just plain dreary - not so much the rain but lack of daylight.
This should be a stock '86 4+3 BIN:
86 4+3 bin
This should be a stock '86 4+3 BIN:
86 4+3 bin
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
Yeah, it really isn't that rainy but overcast, yes. I can't say I miss that, but I'd like a bit more rain than we get now. Plus, that Seattle air. You don't know how clean it is till you've spent time in the California valley air 
Thanks for the bin!
Thanks for the bin!
Race Director
Joined: Jun 2009
Posts: 10,428
Likes: 9
From: Southside of Western Norte Americano State of Confusion, ColoFornia
St. Jude '13
This brings up a question, I recently converted an 85 with 4+3 to a Carb set up because of Bolloxed wiring etc.. so.. Since I have disconnected the TPs and the other engine control sensors.. is this going to cause trouble with the overdrive?? or will it revert to manual without the TPS signal?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Run the tan/blk wire to ground through a switch
(the stock O/d switch is a signal to the computer; not a wire to the O/d itself )
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