VS Commodore Auto to manual conversion

Points
22
Location
Australia Cessnock
Car
VS crankydore
Here's an interesting topic.
After searching the web for good info on how to convert a VS auto to manual I found only a small amount of info. It does tell how to cut and add a wire here and loop a wire there but then goes on to the getting the mamcal retune etc which starts costing a few extra bucks on top of the parts bought for the conversion.

I found that the GREGORY'S sevice book has all the wiring diagrams needed for the job to allow for the factory Manual computer to plug straight in to the Auto loom. I picked up a manual computer for $100 so saved afair bit through not needing the manual loom which is hard to find.

The main problem people were having was car stalling at lights etc due to speedo sensor issues. It shows in the Gregory's service book that Auto voilet/white wire which is feed for speedo is located in different pin positions to the manual aswell as the auto computer recieves the info from speed sensor and converts it to a pulse signal for the speedo and cruise control but Manual has the speed sensor send the pulse signal to computer speedo and cruise control. When someone cuts and shuts the other way the signal is lost and the computer goes into limp mode. Then a mecal fix gives it the Idle revs info etc. There is other wiring that needs disconecting from the auto loom at computer to eliminate conflict + a 12v power wire is readily available from the auto trans wiring that comes from the same fuse location as the manual to feed the speed sensor. Don't know if anyone is interested in this but there you have it. If anyone needs the full info on how to I'd be happy to ablige:D
 
Mate you hit the nail on the head, there are mixed opinions on this topic but what you have posted makes a great deal of sence to me and I hope you can shed some info on the change over?
I have a 97 VS Clubby 5ltr Auto, got a T5 for it with a Manual ECU.
I was told by they guy I bought the box off that the reverse set up hooks straight into the Auto Harness? But other people say no it doesn't?
Also the T5 is out of a VP ute, so hope it will bolt up to the VS?
 
Sorry for the delay in reply. I've been busy to say the least.
The 5ltr is a slightly different setup but does have some requirements you need to consider.
To answer your Q:
It will bolt up (provided its V8 to V8) but you will have differences to deal with like,
memcal recal to fix stalling issue,
lume needs "modifying IF you intend to use a manual ECU from a VS commodore (it would not be an easy task to find a VS V8 manual ECU but not impossible.
(I did take some pics of the modifying I did to the lume should you need to see them)
As far as the reverse light switch goes, that's an easy job of running a couple of wires from the switch at the Gearbox through the firewall/or floor to the plug that has the switch at the drive selector, along with this job you'll need to loop the neutral start wire so the starter motor will activate or leave the switch that operates the neutral/Park position switch and leave it in the park or neutral position . Should you need specifics I can get pics of mine as I'm about to pull it apart again for the fix I'm about to mension.
Some people would to leave the lume and use the auto ECU and convert the memcal. The only issue is the different sensor setup from AUTO to T5.
Though from memory I think I remeber that there is a difference with the V8's that might make it easier. I'll check it out.
I think the best option is what I did which is to use the auto loom but change & disconnect the necessary pins and convert it to being a manual loom. It's not hard.
The plugs are the same on auto and manual. Just the pin postions change for auto speed sensor or T5 speed sensor and disconecting the auto solenoid specific pins that tell the ECU about the gear change timing etc.
Q:Are you converting all the parts from a VP ie tail shaft,lume,ecu, T5 etc and is the VP ute a V8?
Tailshaft probably wont fit (unless the VS is a ute aswell)


I'm not sure if the V8's had externally balanced cranks aswell. It would seem they do when you look at the V8 flywheels. Its a big warning to check out cause you'll need the flywheel to be mirror balanced to the flex plate FROM THE ENGINE IT CAME FROM
OR
get a flywheel (if available) through;
MARKS CONVERSIONS
they have a unique setup where they machine the flywheel out of billet steel to be neutral balanced and that the flex plate bolts to the flywheel so the flex plate from the same engine keeps the factory balancing. That flywheel would set you back $400 plus postage. The only downer I see is that after going to the trouble of converting and having the opertunity to go lighter with the flywheel, this option weighs in at +- 13kg's.
OR
Get it through DELLOW AUTOMOTIVE!!?? will check their business name and correct it if needed.
Their option is also billet steel and the same price but they dont use the flex plate other than to check that they are providing the right flywheel for the application.
The owner of the company has gone to HUGE lengths to get the weight references of each model engine ie: early VN to VS-VT and so on. probably more. (PS: I have those weight references here too as he emailed them to me, should anyone want them)
They machine out the weight "offset" when CNC machining.
This is the option I think I will go for but I do still need to find out the total weight of the flywheel. (I'm guess their's will be around 10kg's).
They can only get close to the correct OFFSET weight for the engine though because each and every engine/crankshaft has it's own unique balance requirement. (hence to use this option it would be best to have the crankshaft and all components balanced for a perfect balance.
( I would like to state though that the buick engine was notoriously bad for vibration issues and that they went to great lengths to "TRY" to rectify the issue by adding a balance shaft, even the harmonic balancer would be specific to each engine/crankshaft and ofcoarse the external balancing of the flywheel.)

My home made F/W weighed in at under 10kg's. The stock 8 bolt is nearly 11KG's.
Then to top it off the one I made had the mass of the weight in close to the centre where as the stocky has it at the outer circumference.
I have finally finished my conversion and have been driving it for about 5 months.
The difference is fantastic. Better response and most of all heaps better economy.
with the auto I was very luck if I would get 7:1 fuel ratio.(7 k's to the litre)
With the manual and so far with the same diff ratio I have been getting as good as 11:1.
but on average 10:1 ratio. The 10:1 is driving how I like to though [HARD:)].
My biggest issue was the flywheel.
with the 3.8ltr V6 they are externally balanced as previously mensioned and I couldn't find anyone who would mirror balance around newcastle (NSW AUSTRALIA).
What I ended up doing to save on cost was to remove the counter weight from the flex plate and fix it to the flywheel. (the flywheel was a 6 bolt F/W from a VN commodore + adaptor plate that I made to convert it to 8 bolt)
that is a story in itself that I'll go into further if wanted. It did work well though and saved me $400 bucks for an after market flywheel which would still require me to have the engine and components balanced for a proper job.
The only issue I still had to fix was an occasional stalling when coming down to idle at lights. Even though I used a manual ECU to try to avoid this issue. My guess is that the T5 has a speed sensor with the ratio in the box telling the computer it is a 3.4:1 diff ratio and I was still using a 3.08:1 diff ratio plus who knows what ratio the ECU is expecting to recieve. I still need to hook it up to my laptop to do the final recal
(I installed an NVRAM so I will be able to tune and retune aswell as tuning on the fly basically giving me a built in dyno tuner but better as it allows real time tuning, but that's another story to tell if your interested)
I have had drama's since though as the engine has developed a severe shake at
2000rpm. When doing the conversion I check the "squareness of the mating surface at the end of the crankshaft where the flex plate was bolted to. It was NOT square!! by about .1mm!!. That equates to alot at the outer circumference of the flywheel.
To fix this issue I spent 3 !DAYS! filing the crank by hand and rechecking with micrometer to get it square.
I was pressed for time and cash to finish the car so we could use it :()
I still have the original engine from my VS commodore sitting here (another story) with the heads off so I will be porting the heads for it and possibly buying the $400 flywheel for it.
(Just incase the damage WAS caused by my flywheel).
I will be pulling it down soon to diagnose & fix it.
(This time I bought another VS commodore for cheap to get around in so there's not as much of a hurry)
I'm pretty sure that the crank was on it's way out prior to the conversion though
as it always had a vibration when it was an auto aswell. the difference was that the Auto had the flex plate and torque converter to take up and hide the shock.
I'll leave it at that for now. Let me know if there's more you want to know or need to find out.
Cheers Paul
 
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Greetings Holdenallong and a Warm Welcome to our TorqueCars Forum my Friend!

Good to have you along with us :)
 
Thanks guys! And thanks for the info! I have since swapped the VP t5 back to the guy for a VSSS T5 as he tried to fit this box to his VL but the SS box didn't match the Bell Housing, he must have given me the SS housing n tried to bolt the SST5 to VP housing so we just swapped boxes witch was a good idea, at least it's a VS Box same model as my car. My VS vibrates slightly as well with the auto at a certain RPM especially if I gun it, I thought maybe tail shaft uni stuffed but mechanic said its ok, then I thought it may be out of balance. I asked him about the crank balance, he said should be ok but I am suspicious about it and now u mentioned this in your reply makes me sure it's the crank, have been thinking that this is the drama for a while which is not cool!! I am yet to do the conversion, will catch up with the Mechanic and see how much experience he has with it. I am chasing fuel economy and "GRUNT" but mainly economy! My VS liter meter says 10.5 to 11.1 to the k on highway, average around 450 500 to a tank of juice so with the conversion will be good!

Cheers.
 
Here's an interesting topic.
After searching the web for good info on how to convert a VS auto to manual I found only a small amount of info. It does tell how to cut and add a wire here and loop a wire there but then goes on to the getting the mamcal retune etc which starts costing a few extra bucks on top of the parts bought for the conversion.

I found that the GREGORY'S sevice book has all the wiring diagrams needed for the job to allow for the factory Manual computer to plug straight in to the Auto loom. I picked up a manual computer for $100 so saved afair bit through not needing the manual loom which is hard to find.

The main problem people were having was car stalling at lights etc due to speedo sensor issues. It shows in the Gregory's service book that Auto voilet/white wire which is feed for speedo is located in different pin positions to the manual aswell as the auto computer recieves the info from speed sensor and converts it to a pulse signal for the speedo and cruise control but Manual has the speed sensor send the pulse signal to computer speedo and cruise control. When someone cuts and shuts the other way the signal is lost and the computer goes into limp mode. Then a mecal fix gives it the Idle revs info etc. There is other wiring that needs disconecting from the auto loom at computer to eliminate conflict + a 12v power wire is readily available from the auto trans wiring that comes from the same fuse location as the manual to feed the speed sensor. Don't know if anyone is interested in this but there you have it. If anyone needs the full info on how to I'd be happy to ablige:D


Hey mate, just about to do this exact conversion myself and thought ive had a look online for some answers and stumbled upon this. Only problem is i don't have a gregorys and you probably don't remember how u did it all them years ago haha
 
Here's an interesting topic.
After searching the web for good info on how to convert a VS auto to manual I found only a small amount of info. It does tell how to cut and add a wire here and loop a wire there but then goes on to the getting the mamcal retune etc which starts costing a few extra bucks on top of the parts bought for the conversion.

I found that the GREGORY'S sevice book has all the wiring diagrams needed for the job to allow for the factory Manual computer to plug straight in to the Auto loom. I picked up a manual computer for $100 so saved afair bit through not needing the manual loom which is hard to find.

The main problem people were having was car stalling at lights etc due to speedo sensor issues. It shows in the Gregory's service book that Auto voilet/white wire which is feed for speedo is located in different pin positions to the manual aswell as the auto computer recieves the info from speed sensor and converts it to a pulse signal for the speedo and cruise control but Manual has the speed sensor send the pulse signal to computer speedo and cruise control. When someone cuts and shuts the other way the signal is lost and the computer goes into limp mode. Then a mecal fix gives it the Idle revs info etc. There is other wiring that needs disconecting from the auto loom at computer to eliminate conflict + a 12v power wire is readily available from the auto trans wiring that comes from the same fuse location as the manual to feed the speed sensor. Don't know if anyone is interested in this but there you have it. If anyone needs the full info on how to I'd be happy to ablige:D
i know that this is quite some time ago but i need some info please to perform a very similar issue. VSV6 auto loom and PCM (no BCM or KEY) to 'manual' transmission

I have an ecotec in my hilux with the TCV cable control for shifts etc (TH700/4L60) NOT the electronic version. I use a switched external 12v supply wired through the 4th gear switch in the trans for the TCC lockup)

Currently its running on a VP commodore loom and ECU, but i feel it would be better with the full ecotec loom? im having performance drop off issues when at operating temp? pulls like a train when cold but power drops markedly when hot. does not have any idle, stalling issues or misfiring whilst running on SVI LPG or petrol. so not fuel related?

What im hoping is that i can just get the MEMCAL reset taking out VATS, AUTO trans and FANS (i have these wired separate to the ECU)

Wiring my VSS to the appropriate pin in the PCM etc

Am i heading in the right direction? auto loom has been cut before the transmission plug so hopefully wont cause any issues?

rgds
 

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