f13 gearbox on a 1.2

[johnnynova]

firstly is there a f13cr gearbox (or is it just f13 and not close ratio) and would it be worth putting on a 1.2? just read haynes, there is f13cr so only 1 question.

i ask this because i dont like the ratio of my f10, when changing up even if i rev high in the previouse gear when i change up the revs r too low.


cheers
john

[mark_GSi]

dont think it will fit m8

[Mark]

Yes, it will fit, don't forget about the f10cr aswell.. :D

[nova_rally]

And you'll be wanting a 4.18 Final Gear(Diff) as well - although I think your old F10 had that anyway...

Alan

[Barn]

^^^^ where can you get a 4.18 final drive?

my 1.4 SR (as far as I know has the f13cr???) which comes with a 3. something final drive, lol

cheers

[nova_rally]

Your 1.4SR has a f10wr with 3.94 final, same as mine. 4.18 finals can be found (in f10wr boxes) in the small engined 5 speed boxes (but not the 4 speeds), and some 1.3SRs (or all can't remmeber!). Probably wrong on this bit but I think the SRi has a f10wr with 4.18 final.

Haynes manual has it all - can't find it right now though!

Alan

[Ste_Nova]

sri have f13

[Dicko]

some have f10 ste cuz they have smaller clutches/flywheel/

the later sri's (dispak) had f13's

[Barn]

lol, now I'm confused

!

[MechaT]

1.4SR has F13CR with 3.94 f.drive. 1.3SR has F10WR with 4.18 f. drive.
some engines have 4.53 ratio but I don't think I'll ever find one

F13 will fit your 1.2, mate

I've been researching this all exhaustively for weeks now and its driving me nuts!:crazyeye:

[Ste_Nova]

1.4sr have f10 i have one here as it came from the factory... i can get the numbers off the box is anyone is intrested i also have an e reg 1.2 engine with the optional 5 speed fitted
http://uploader.co.uk/showimg.php?i=gearboxcodex.jpg

not sure if this is correct :lol:
http://uploader.co.uk/images/gearsx.jpg

[Snowface]

that means my 5-speed that's in my merit has a final of 4.18.

So is that good?

Is the CR beter for Quarter Miles? And WR for top end?

Also what's the diff between the F10cr and F13cr?

Is it the amound of torque or power they can handle (130bhp?).

Is thje F15 better than the F10 and F13?

[Dicko]

lol

ye ste iv seen lots of guides like that but non have been right. think vuax just mixed n matched and put on wotever was available at the time to a certain degree

[nova_rally]

My SR also has the f10w 3.94 box. I've yet to come across 1 with the f13cr 4.18. That would have some decent performance then! :lol:

Optional Extra perhaps? (bit of a weird option though....)

Alan

[mikeoxford]

in reply to snowface as far as the F numbers are concerned AFAIK the higher they are the higher the BHP rating yes correct.

the boxes are a right mix and match

me and CP had a right laugh looking at 3 gearboxes and his haynes manual when we did my swap. none of them tallied!

as an aside.........

stugsi has an A reg SR, and that is fitted with a wide ratio 4.18 - as far as we know, its standard issue.

[MC]

As mentioned previously, Vaux mixed and matched gearboxes as they went along. Any guide or haynes manual cant cover all combinations. As a rule of thunb, a close ratio box has a longer final drive, and a wide ratio box has a close FD.

Examples:

J plate 1.4 SR F10CR with 3.74 FD

F plate 1.6 GTE F13WR with 4.18 FD

WIth both of these examples we counted the teeth on each cog to confirm the ratios. Interestingly, each gear was different to that stated in the haynes too.
Visit the breakers yard and use the diagram that STE posted to establish whats in each one. The internals of the f10, 13 and 15 are interchangeable. An f13 from a GTE/GSi will not fit on a 1.2, 1.3 or 1.4 as the bell housing is bigger, best bet is to swap the internals over which come out complete as a magazine. Drive shafts need to come out to change the FD over.

The f number of the gearbox is rumoured to be the torque rating of the gearbox, but when you strip the different boxes apart you can see that there is no difference in the construction and durability of the internals, so I'd take that with a pinch of salt.
The 4.53 FD is available in 1.2 and 1.3 Astras and 1.2 and 1.4 corsas, I'd guess wide ratio boxes.

[Aragorn]

the f13 from a 1.6 gte will fit a 1.4 (and by inference the 1.2 and 1.3) cos ive got one on mine - the mounting points are the same - theres just more room inside the bellhousing for the 1600 flywheel

u just cant fit the smaller bellhousinged F10 to the 1.6 engines

[MC]

I stand corrected.

[rgv_stu]

my 1400 sr has a F10 C/R 3. summot fitted.

and yes it is a c/r

[Dicko]

im still looking for a 4.18 FD if anybody has one. ive got a 3.74 and 3.94 if you fancy doing a swop :D

[nova_rally]

On what year Astra's are the 4.53s fitted? I have a mate with 3 Astras, once of which is being broken (1.3 engine's mine and the head off it's in my nova at the moment). Thats a 1986 Astra (mk2).

I'll check on my gearbox what my Gearing is as when I originally got the car I was told it was close ratio, but I know it's got a 3.94 (rubbish) final!

Alan

[MC]

I believe it was MK1's.

It might be a CR box you have, if it was a 4.18 final drive it would not be! They didn't put the 4.18 drive with the CR cluster as it dropped the top speed too much and you'd be at high revs when cruising. I could only do about 120 at 7,5k rpm, so a limited engine would only do about 110mph

MC

[Ste_Nova]

stugsi has an A reg SR, and that is fitted with a wide ratio 4.18 - as far as we know, its standard issue.

lifted from the mk2 cav 1.3

[benji]

so to clear things up.

i have a 1.4sr engine. that is attached to a 5 speed 1.2 box.

what fd will be in the 1.2 box and what is the ideal box to use on my car for acceleration.

cheers

ben.

[johnnynova]

???? if you have a close ratio box (cr) ie f13cr or f10cr your top speed will be reduced, but you will gain alot in acceleration, novas arent motorway mile munchers so why bother, they r quick little pocket rockets unless u have a 2.0 conversion or 1.8 etc.

am i mising the point here as people want cr boxes with 4.38 or sumtin final drive, you cant ge that, the gears have less difference in them thats how yo get quicker acceleration, so no way r u gonna get a higher top spped with a cr box compared to a standard box.

just look in haynes to see!

if i change my standard f10 to a f10cr or f13cr when i am in 5th gear on the cr boxes it is the same as being in 4th gear on the normal boxes.

[nova_rally]

I know exactly where I can find a Mk1 Astra so I'll try and take a look if I can!

yes it is possible to have CR boxes with 4.53 finals - but top speed is limited to 105Mph. Who really cares about that anyway? how often do you really get the chance to go that fast? what's really fun is being able to leave people standing - Nova's cant do that as standard!

Alan

[MechaT]

The F10 on my 1.3SR says W4.18 (wide ratio 4.18 final drive) and all the 1.3 SR boxes I've seen have been the same. The code on the GTE box I have says W3.74. according to Haynes manual and that PNG chart it should be a C3.74.

I reckon Vauxhall just bolts on whatever box the fitter happens to trip over on the workshop floor. Vaux gearboxes suck. :bad-word:

[MC]

Johnynova, what are you going on about? Nobody said that a CR box will give a higher speed. :lol:

The whole point of this post is to establish what combinations and from where will give the best acceleration.

I also came to the conclusion that Vauxhall just bolted on what they had to hand.

MC

[Stuart]

they used/use that ethos with the entire car dont they lol

[CP]

The reason for the continued debate on Nova g/box ratios is for 2 reasons:
1. There is a lot of confusion over whats in what - Vaux didnt record what it actually screwed into what accurately.
2. Anyone who has driven a GTE or GSi with the wide ratio box and long final drive knows that you cant get full revs in 5th cos the gearing is too long. Often 4th is the fastest for top speed. This was IMO Vaux trying to give some motorway cruising ability for the 1.6 with good petrol consumption. So the nova being a pocket rocket with good accelration and no motorway use isnt true for all Novas. If you have 1 of these boxes getting it sorted can make a huge difference to feel and performance

[Snowface]

so to clear things up.

i have a 1.4sr engine. that is attached to a 5 speed 1.2 box.

what fd will be in the 1.2 box and what is the ideal box to use on my car for acceleration.

cheers

ben.

that'll be most likely a F10wr with 4.18fd like mine.
Especially if its made between sept '88 and sept '90.

I quote from Max Power Haynes manual for Nova.

Sept '88
All 1.2 models fitted with new 5-speed box.

Sept '90
Blah blah blah... 1.4sr fitted with new close ratio gearbox.

[nova_rally]

Well that last bit's wrong as my August 1991 1.4SR has a F10WR!

(Still it's nice and quick with the new head on it!)

Alan

[MC]

Snowface. If you have the box in your possesion, use the diagram that ste provided and have a look. Simple, its the only way you will know for sure.

MC

[Stuart]

and then take it appart and count the teeth lol

[Snowface]

if u look at the post i'm quoting benji.