5 speed box

[davehaynes]

got a mk2 merit, 1.2 carb engine currently 4 speed but i want to put a 5 speed box on it, what box will bea straight swap?
thanks.

[ck]

any 5speed should be a direct swap. f10/f13/15 will drop straight in. the f10's have a smaller bellhousing but this wont make any diffarence as your 1.2 will have the smaller flywheel ect.

[ck]

oops another thing is you will have to cut the small lug off of your gearstick to allow you to engage 5th aswell

[davehaynes]

yeahh i read about cutting something off in another thread. so f10 f13 f15 will be 5 speed boxes? and are they the only ones? cheers.

[garyc]

You could alwaysd swap the cluster for a 5sp one, I have one for sale in the forsale section.

[ck]

f10s can be 4speed aswell. you can tell by looking at the cover on the end of the gearbox, the 4speed will have a big nut/hexagon. wheras the 5speed only a small one.

so yep any f10/f13/f15. some f13 and all f15s do not have the inspection cover on the bottom so coudl be wise getting one with the cover as it will make life a breeze if u ever need to change the clutch.

to make sure its 5speed you can physicaly change into each gear by the selector on the top of the gearbox, if its not 5speed the selector wont twist into the 5th position..

[davehaynes]

whats swapping for a 5 speed cluster? :S
don't know much about mechanics lol

[Dod]

Find a scrapped Astra, Cavalier 1.6, Corsa, Nova, take the box out, fit it to yours and Jobs a goodun.

[loggyboy]

Check you gearbox, as you may have a 5 speed already, some novas came with them but had a plastic restrictor under the gear stick gaitor that stopped them from engaging the 5th gear.

[davehaynes]

ohh ok lol but check it for what? :S

[Dod]

Try putting it into 5th gear is what he means. Just trim the bit off the lever.

[davehaynes]

ohhh yeah worth a try:D fingers crossed then i could already have a 5 speed

[loggyboy]

The gearbox should have diagram on the top of the selector box.

[AlexW]

The gearbox should have diagram on the top of the selector box.

Means nothing, even 4 speed f10s had that diagram.

[davehaynes]

is there anything i can check for on my box which will indicate if its 4speed or 5 speed? codes, stamps, etc?

[garyc]

If you do a search this was covered a couple of months back. Theres pictures which make it easy for you to see whats going on!

[AlexW]

is there anything i can check for on my box which will indicate if its 4speed or 5 speed? codes, stamps, etc?

If you can take a look at the end plate on your gearbox (behind the passenger wheel, put it on full lock) it should have a small or big nut or possibly none.

Edit: As i scrolled up i saw Ck had already posted this.

[mowgli]

Check you gearbox, as you may have a 5 speed already, some novas came with them but had a plastic restrictor under the gear stick gaitor that stopped them from engaging the 5th gear.

Where did you get that info from????????????

they would have never fitted a 5 speed & blanked one off, the car would just rev its nuts off going down the road.

Easiest way to check is to look at your gearbox.

a 4 speed is 1 big casting with a little casting on the end(which has a 36mm hexagon plug in it)

A 5 speed has a big casting, & 2 little castings (one is the bit the 5th gear goes in)

I would recommend to also change the whole gearstick to a 5 speed because it will have a 5 speed gearknob on it.

You will not get any appreciable performance gain from having a 5 speed in a std 1.2.

If you buy a f13 box, then in the future you want to stick a bigger engine in, a 1.3, 1.4 & 1.6 will all go straight in

[Welsh Dan]

I've had a 4 speed and have a 5 speed box in my 1.2, 5th really helps on the motorway.

A 5-speed looks like this:
http://www.xen0phobiak.f2s.com/novaload/5speed.jpg

I can't find a picture of the 4-speed that I accidentally fitted to my car lol.

[mowgli]

as a std 1.2 4speed has a 1:1 top gear & a 3.74:1 diff, & does 20mph/1000rpm, what ratio box did you fit???

[Welsh Dan]

F10 4 speed and F10 5 speed. I found that at 70mph on the 4speed box i was doing around 5000rpm, whereas in 5th I do just under 4000rpm, so 5th gives more leeway for overtaking, if the wind and gradient allow. :)

[mowgli]

did you fit a different dash???

back in the old days (cue hovis ad music)
my first nova (1.2 4speed) would run to an indicated 85 in third, & 95 indicated in top.

as I said about the 1.2 gearing, 70mph in top is at 3500rpm, if it could pull 5000rpm in top (down hill outrunning a cyclone) it would indicate 100mph....

[Welsh Dan]

I did, but long before the temporary 4-speed fitment.