5 Speed Conversion!

[Clatters]

hey, how easy is it to swap a 4speed gear box for a 5? because doin 70 in fourth is killin my nova! she needs a top gear! any help and guidance would be much appreciated!
cheers

Ps. can you do anything to a 1.2 engine to get a little more performance?
thanx

[Welsh Dan]

Pretty easy actually. Get the car up on axle stands, support the engine with a jack or some blocks, remove the driveshafts from the gearbox, disconnect the reverse gear sensor and the horn, remove the clutch cable and gear linkage. Then remove the bit bolts that hold the gearbox to the engine, then support the weight of the gearbox while you undo the passenger side and rear gearbox mounts from the chassis. Pull the gearbox out to the passenger side and it'll fall off with some persuasion.

To fit the new box, remove the end cover, and take the circlip out of the inside of the input shaft (left one), this will allow you to push the inout shaft into the gearbox from the clutch side, which makes getting the box on much easier, fit the box then push the input shaft back in and refit the circlip and end cover remembering to reconnect the earth strap. Check the gearbox fluid level by removing the plug just above the passenger side CV and topping it up with gearbox oil through the top of the selector, until fluid drips from the hole where you removed the plug, then put the plug back in.

Check that your gearstick goes to 5th, if it doesnt then lift up the gator and remove the lug thats blocking it. Allign the gearlinkage and adjust the clutch cable to get the biting point where you want.

[Adam]

Your 4 speed will be long ratio tho, so a 5speed box will still leave engine revs at a similar speed as with a 4speed.

[Ash]

Ps. can you do anything to a 1.2 engine to get a little more performance?
thanx

Cliff, push - you get the idea....

No really, you can do anything you can do to a 1.3 or 1.4. Is it carb or injection? You could spend a little money here and there, but with better engines going so cheap these days, you might as well swap when insurance, etc allows. Till then just service. You could always fit an air filter or exhaust to make it sound lik your going faster lol

[dannyb]

Ps. can you do anything to a 1.2 engine to get a little more performance?
thanx

Do the other bits - decent tyres (with light wheels!) suspension and brakes etc, 1.2s can still be fun with these changes! You'll be better off financially by buying a 1.3 or a 1.4 engine in future rather than trying to achieve the same power from the 1.2.

[Jack]

Good notes on gearbox change.

As for performance, yes you can squeeze more power from the 1.2 (see Stu's old 1.2), but ?-per-bhp there's better things to do. As said, think about other ways to make the car faster - namely handling; stripping out the interior saves you weight and costs nothing (selling interior parts may even earn you a penny or two), fitting better tyres & brakes allows later braking (think ATE calipers and 256mm discs, and some sticky tyres), fitting quality suspension allows better control through corners.

Also bear in mind mods = higher insurance premium.

[Welsh Dan]

Also bear in mind mods = higher insurance premium.

Yes, but sticky tyres on standard wheels, good discs+pads using the standard calipers and some decent shocks using standard springs arent classed as modifications :). Because any parts you use to replace those with when servicing the vehicle are unlikely to be the exact same spec as the factory fitted ones, they tend not to count.

If you were to start fitting 256mm brakes, bucket seats etc.. then you're right the premium will go up, but there are things you can do that wont effect the insurance.

[craig green]

Fitting a 1300 or 1400 engine makes far more sense than tuning a 1.2 tbh. The difference is huge.

5sp boxes (F10 or F13) can be found in CR or WR format.

The best mod I did to my 1.2L was putting on Cav steels with 185mm tyres. I was 25 mins quicker to Uni that weekend!

[Clatters]

cheers for all of that.. so i wont need a new clutch and drive shaft and all the other gubbings, if i swap for a 5 speed? because talking to one of my m8s whos a mechanic said it was a big job looking to cost me alot? im not interested if its guna drain my account so i cant do other things to the car?

i will leave the engine as it is then just keep it serviced and clean!

[Welsh Dan]

No, you can use your existing clutch, driveshafts, clutch cable, gear linkage and mounts. I forgot to mention swapping the mounts over in my instructions earlier, torque up the bolts from the box to the mounts fairly tight and use some loctite on them, I had 1 come out completely and another half out on the drivers side mount and i had done them up tight!

It took me the best part of a day when I swapped mine from 4speed to 5-speed (after i'd just fitted the 4 speed attached to the new engine lol), but If I was to do it again I think I could get it done in less than 2 hours, its not a massive job once you're familiar with what to do.

[Clatters]

i will get my freind to help he has a pit.. and all the tools to do this properly so i assume we can have it done soon! especially as he has been working with cars for 30 years!
so any ideas of prices for the box? and is the best place ot look scrappies?

[Welsh Dan]

You can probably pick up a 5-speed box for ?30-80 on here depending on whether its an F10 or an F13 and what ratio/final drive.

Its in german, but this shows what is available:
http://www.xen0phobiak.f2s.com/novaload/gear_ratios.jpg

The lower the numbers, the lower the rpm's at a given speed. The higher the numbers the faster the acceleration.

[craig green]

Yeah a scrapped Astra with a 1400cc engine should be a good/easy source for a box. Dont pay any more than ?50 IMO.

[Clatters]

so i need ot find wat one i have and wat one goes with it yeah? or does it not matter? sorry just not that knowledgeable about this!

[craig green]

You have an F10 4spd. Any F10, F13 or F15 will fit.

As the number goes up they are supposedly stronger, from 1600's etc.

Look out for which type they are, a CR box is close ratios like from a GTE or GSi, this will have a lower final drive which means the engine revs higher per gear, great for acceleration but poor for economy or relaxed motorway cruising. As your 1.2 isnt a particularly high revving engine it wouldnt make sense but if you wanted to keep the box in mind for a bigger/better engine in the future, it would be an option.

[maccas]

i have an f10 5 speed box from a 1992 1.2i luxe plus its done around 80000 miles you can have it for 15 quid if you want it but your a hell of a long way away from me so would probably have to courier it, let me know if your interested

maccas

[maccas]

it used to do 70 in 5th at 3000 revs as far as i remember just so you know

maccas

[Clatters]

That is tempting m8... i dont get paid for 2weeks.. but if you could find out wat the carrage would cost ontop of the ?15 if it is not to much i will take it off your hands... let me know... joe