Mk2 1.8T gearbox questions

[benji mk2]

Right then,

 I'm planning on putting a 1.8T into my MK2 in the non to distant future but the current gearbox is doin my nut!!!  As far as i can gather the standard mk2 box (020) will work with a 1.8T, is this correct? If so i plan on getting the box rebuilt with a nice lsd and possibly a longer fifth to aid motorway cruising. Does anyone have any input on doing this?


  Cheers!!!!!!!!!

[Skid]

Yes, see the Qpeng site (ggogle it) as their demo is running the original box, it's just a hybrid clutch arrangement apparently.

I'm very interested in this also but haven't had time to go into the finer details so if you find out more please post here as would be very interested to hear.

Maybe a gearbox specialist would do a deal on 2 box's as per your suggestion??

Mark

[benji mk2]

i found a place in ellsemere port that said it would charge about £150 for the labour to rebuild the box, plus parts. I found a bit of info that said using a 0.75 fifth instead of the standard 0.89 will reduce the motorway cruising revs??!! I have no idea where i could get one tho. Looking at about £550 for a 1.5 LSD, unless anyone knows different?

[Mk2Kezza]

You can get a 0.75 fifth gear out of  a 4T like I did - they came in 1.6 drivers apparently. There are several other gearboxes which would have the 0.75 gear in, but I don't have the link to the site which lists the ratios. Just do a search on here and you should be fine. www.sirocco.org may have the ratios thinking about.

My box cost me £15 with the engine from flea-bay! A garage fitted mine while the new 2nd gear synchro was going in as the 5th gear cogs had to come out anyway.

[benji mk2]

nice one cheers,   erm prob being stupid but whats 4T???

[Mk2Kezza]

Sorry mate. A 4T is a gearbox code, and those boxes came with the 1.6 driver. My 1990 8v GTi has an AUG box. What are different about them are the gearing ratios. The 4T for instance has longer gearing in most of the gears to allow for comfort driving, whereas the AUG box has closer ratio gears for better acceleration. The 5th gear in a 4T is 0.75 and 5th in an AUG is 0.89. I swapped them over as I do alot of motorway driving and wanted lower revs for smoother cruising and better fuel economy.

e.g

AUG @60 mph = 2900 rpm
4T   @70 mph = 2900 rpm

Pulled those figures off the top of my head but that’s about the difference or drop in revs between the two ratios. In real terms it means I get about:
43 mpg @ 70 mph
40 mpg @ 75 mph
36 mpg @ 80 mph
33 mpg @ 85 mph

I certainly wasn't getting those sorts of returns with the 0.89 cogs, more like:

44 mpg @ 60 mph
36 mpg @ 70 mph
33 mpg @ 75 mph
<32 mpg @ 80 mph and above.

So it was worth it for me. You will lose some acceleration with a standard GTi engine but she still pulls well. With a 1.8T it would still go like hell - a good alternative to a 6 speed box.
 

[MX210]

Hi,
You seem to know quite a bit about gear ratios do you kno anything about crown wheel and pinion  ratios. I want my 8 valver to excelerate quickly up to about say 80 not looking for real top end just want it to go like hell off the mark, can you help?

[benji mk2]

totally forgot about this thread, cheers for the info Mk2Kezza, spot on dude!!!!!!!