996 GT3 gearbox
Discussion
Hello,
The gearbox from a MKI car is slightly different, the gear ratio for 5th and 6th gears is different. It does not have steel synchronizer rings on 3rd/4th/5th gears as a MKII, and no oil pump on a MKI. 3rd/4th selector for is machined out on the MKII gearbox to allow clearance for the oil pump drive gear.
Jesus I do need to get out more !
Just rebuild the MKII gearbox
Mike
The gearbox from a MKI car is slightly different, the gear ratio for 5th and 6th gears is different. It does not have steel synchronizer rings on 3rd/4th/5th gears as a MKII, and no oil pump on a MKI. 3rd/4th selector for is machined out on the MKII gearbox to allow clearance for the oil pump drive gear.
Jesus I do need to get out more !
Just rebuild the MKII gearbox
Mike
Hey Mr. Irfan..
Hope you are well... your car is looking splendid sir!!
Mike rebuilt my mk1 gearbox last year to a decent spec, all new bearings & seals, steel syncros, cup diff kit & cup c&p kit.. also fitted a steel mech' 7.2 shifter & cup cables.. as you would expect the box is now utterley brilliant and a joy to use!
Mike may not be able to drive for toffy.. lol.. but he does know his gearboxes!!!
Ade
Hope you are well... your car is looking splendid sir!!
Mike rebuilt my mk1 gearbox last year to a decent spec, all new bearings & seals, steel syncros, cup diff kit & cup c&p kit.. also fitted a steel mech' 7.2 shifter & cup cables.. as you would expect the box is now utterley brilliant and a joy to use!
Mike may not be able to drive for toffy.. lol.. but he does know his gearboxes!!!
Ade
Hi Ade. Am a bit gutted about not being to unleash the car after the engine rebuild - it's been in for 5 months and I'm having serious withdrawal symptoms.
The issue with the gearbox is there are very few people capable of doing the 'box rebuild out here, so I'm trying to tie one chap down who did the Cup cars in the domestic GT championship.
The issue with the gearbox is there are very few people capable of doing the 'box rebuild out here, so I'm trying to tie one chap down who did the Cup cars in the domestic GT championship.
understood. wasnt sure if it was a terminal issue or just a niggling one.
ade, you go full steel synchros on there or 3,4 and 5 like the MK2 box?
mike, whats the valve gubbins on the MK2 box heat exchanger do? i assume just select when the exchanger is active but any ideas what control is? gearbox temp triggers valve to open to regulate it, engine temp prevents it doing anything until everything is warm this shortening warm up times or none of the above at all.
ive always wondered since i saw all that plumbing on the mk2 box.
ade, you go full steel synchros on there or 3,4 and 5 like the MK2 box?
mike, whats the valve gubbins on the MK2 box heat exchanger do? i assume just select when the exchanger is active but any ideas what control is? gearbox temp triggers valve to open to regulate it, engine temp prevents it doing anything until everything is warm this shortening warm up times or none of the above at all.
ive always wondered since i saw all that plumbing on the mk2 box.
fioran0 said:
understood. wasnt sure if it was a terminal issue or just a niggling one.
ade, you go full steel synchros on there or 3,4 and 5 like the MK2 box?
mike, whats the valve gubbins on the MK2 box heat exchanger do? i assume just select when the exchanger is active but any ideas what control is? gearbox temp triggers valve to open to regulate it, engine temp prevents it doing anything until everything is warm this shortening warm up times or none of the above at all.
ive always wondered since i saw all that plumbing on the mk2 box.
Hi Neil,ade, you go full steel synchros on there or 3,4 and 5 like the MK2 box?
mike, whats the valve gubbins on the MK2 box heat exchanger do? i assume just select when the exchanger is active but any ideas what control is? gearbox temp triggers valve to open to regulate it, engine temp prevents it doing anything until everything is warm this shortening warm up times or none of the above at all.
ive always wondered since i saw all that plumbing on the mk2 box.
The oil cooler has gearbox fluid being pumped through it at approx 2.5bar and has engine coolant flowing through the exchanger when the electric valve is opened by engine control unit. It gets the gearbox temperature from a sensor on the gearbox and at 105 degrees it opens the valve allowing coolant to flow through and the when the transmission temperature drops to 95 degrees the valve closes again.
The oil pump system is a good upgrade to the MKII gearbox, again proving you can improve on perfection!
Mike
Thanks mike.
The cup doesn't have any of that. It's just pumping oil and coolant continually through a filter and exchanger so it looked curious when I saw a mk2 box with all the valve stuff on it.
I figured it was to control things but never knew whether it was a closed when engine cold deal so things warmed up faster or as you described, open and closed with gearbox temps.
Thanks for info.
Ade. I wouldn't sweat it mate. Just change your gearbox fluid once a year. If you were keen on doing something you would be better putting on an electric pump, filter and an oil rad that's air cooled anyways. tap a feed and return line to the casing.
The cup doesn't have any of that. It's just pumping oil and coolant continually through a filter and exchanger so it looked curious when I saw a mk2 box with all the valve stuff on it.
I figured it was to control things but never knew whether it was a closed when engine cold deal so things warmed up faster or as you described, open and closed with gearbox temps.
Thanks for info.
Ade. I wouldn't sweat it mate. Just change your gearbox fluid once a year. If you were keen on doing something you would be better putting on an electric pump, filter and an oil rad that's air cooled anyways. tap a feed and return line to the casing.
fioran0 said:
Thanks mike.
The cup doesn't have any of that. It's just pumping oil and coolant continually through a filter and exchanger so it looked curious when I saw a mk2 box with all the valve stuff on it.
I figured it was to control things but never knew whether it was a closed when engine cold deal so things warmed up faster or as you described, open and closed with gearbox temps.
Thanks for info.
Ade. I wouldn't sweat it mate. Just change your gearbox fluid once a year. If you were keen on doing something you would be better putting on an electric pump, filter and an oil rad that's air cooled anyways. tap a feed and return line to the casing.
Ade can do that on his next rebuild, won't be too far away now!The cup doesn't have any of that. It's just pumping oil and coolant continually through a filter and exchanger so it looked curious when I saw a mk2 box with all the valve stuff on it.
I figured it was to control things but never knew whether it was a closed when engine cold deal so things warmed up faster or as you described, open and closed with gearbox temps.
Thanks for info.
Ade. I wouldn't sweat it mate. Just change your gearbox fluid once a year. If you were keen on doing something you would be better putting on an electric pump, filter and an oil rad that's air cooled anyways. tap a feed and return line to the casing.
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