View Full Version : Gear box differences, the ins and outs...
Ok, I'm down to this now.
I've been told by a mate rallying an XE'd Astra that he runs an F20 casing with an F16 3rd, 4th and 5th gear and shaft but with an F18 1st and 2nd.
First off, is this doable and secondly, is it effective?
Secondly, I've heard of people changing the crown wheel and pinion, why? What does this do?
Ok, now the head scratchiong bit....
I have spare F10s, F13s, F15s, F16s and F20s. I'm building both small and big block cars, what can I mix and match for the best results?
Finially, where on the box does it say weather its a CR or WR box?
not alot of help, but on the end of the box - shaft wise it should have CR or WR stamped into it.
pikey1986
30-05-10, 12:29 PM
i found the stamp on mine stamped just below the end plate, it took some finding but nothing some mr muscle oven cleaner wont shift lol
I've found various different markings and numbers but nothing that actually says WR or CR.
Because it dosnt, it will say like W318 Or C418 etc
the crown wheel and pinion is your final drive
SO by changing my final drive, what are the benifits?
Also, whats the score with interchanging specific gears?
the input shaft is 'fixed' so you cannot change the 1-4 gear ratios without having a new input shaft machined.5th is interchangeable though
oh and the F16 cluster wont go in as there is a bearing that fouls.... it would need to be rebuilt with an F20 bearing there
Ok, cool.
So, I'm still left wondering what difference the Final Drive makes or what it actually does?
basically the lower the FD number the higher your potential top speed (for a given gear) but you accelerate slower, and conversely the higher the number, the lower your potential top speed (for the same given gear(s)) but you accelerate much faster.
there are pros and cons to both, eg with the higher number FD you might wheel spin easier so launches might suffer, and with the lower one it might bog down at launch and so on
Ok, thanks folks, rep given.
general small block rule of thumb is an F13 CR with the 4.18FD
Ok, how do you know what FD your Crown wheel and pinion has?
(I know I need to do a bit of reading up on this)
You could count the teeth, or if you trust it, the end of the box.
My box says W418, as its a Wide ratio gearbox with a 4:18 final drive.
teeth counting is the most reliable way. See my article on the F10/13 FD swap :d
higher the fd the more accel youl have. thats why youd here all da honda boys goin on about there 4.9's higher final drives work better with higher reving cars.
higher the fd the more accel youl have. thats why youd here all da honda boys goin on about there 4.9's higher final drives work better with higher reving cars.
its more the higher FD is better for cars with fack all low down torque lol
F10\F13 CWP's can also be identified by the number of notches in the teeth. ie
6 NOTCH 3:5
5 NOTCH 3.7.7
3 NOTCH 3.9.4
0 NOTCH 4.1.8
1 NOTCH 4.2.2
2 NOTCH 4.5
Mmmm, food for thought. CHeers lads!
F10\F13 CWP's can also be identified by the number of notches in the teeth. ie
6 NOTCH 3:5
5 NOTCH 3.7.7
3 NOTCH 3.9.4
0 NOTCH 4.1.8
1 NOTCH 4.2.2
2 NOTCH 4.5
thats something i never knew, where did you find out that?
on a guide that stock rod lads use. I think it may mention it on EPC to but dont hold that to me!
Ok, I'm gonna get onto this this evening so expect pics and questions. Cheers lads!
this was on an f18:
http://i405.photobucket.com/albums/pp138/sloth_mk1_cav/DSC00190-2.jpg
http://i405.photobucket.com/albums/pp138/sloth_mk1_cav/DSC00191-1.jpg
on a guide that stock rod lads use. I think it may mention it on EPC to but dont hold that to me!dont suppose you have a copy of that do you?
http://www.ybapublications.co.uk/Forum2/viewtopic.php?f=7&t=11
Just for that, I'm gonna get Burgo to sleep with you mate. Cheers!
thats **** hot stuff, just lokked at a mates f20 diff and it has 1 groove in it, so it bears out.
didnt realise it applied to big block boxes too, i wonder what 4 notches is?
4 notches is made of gold and makes the car do an 8sec 1/4 lol
/\ so rick draper spec?
no, it really exists and works...
Ok, I smell a new thread.... (See Muppet for details)
no, it really exists and works...
lmfao!lol
Ok, back on this subject.
Please look at this and tell me where the crown wheel and pinion are.
Ok appoligies for the lack of a picture.
Anyway, yesterday I set about stripping a box to see what was what. I removed the cluster and various other parts until the box was left empty and pictured it as follows.
The Cluster:
http://i3.photobucket.com/albums/y92/Dods1/PICT0383.jpg
http://i3.photobucket.com/albums/y92/Dods1/PICT0382.jpg
http://i3.photobucket.com/albums/y92/Dods1/PICT0384.jpg
The Cluster Casing, its numbered, what do these relate to?:
http://i3.photobucket.com/albums/y92/Dods1/PICT0380.jpg
Can the Final drives be seen from here or do I need more detailed pictures?
Either side of the Diff and the diff holder thingy yokes:
http://i3.photobucket.com/albums/y92/Dods1/PICT0377.jpg
The End casing with numbering stamped on it (possibly the WR/CR or Ratio identification, would anyone care to confirm this?)
http://i3.photobucket.com/albums/y92/Dods1/PICT0379.jpg
The inside when the End Casing is removed, this is the end part of the cluster:
http://i3.photobucket.com/albums/y92/Dods1/PICT0381.jpg
Inside the empty box:
http://i3.photobucket.com/albums/y92/Dods1/PICT0385.jpg
First off, I need to identify the Final drives, secondly, with regards to fitting the diff, I know theres a specific way to tighten it in, but I dont know what it is. Anyone able to help?
milko96
05-06-10, 12:48 PM
Anyone know what 4 nothes on the diff teeth is, as the f13 I just got has 4! and my corsa sport box has 5 but both have 71 teeth and both are meant to be 3.74 FD!?
milko96
05-06-10, 08:35 PM
Ok it looks like the the f13 diff did have 5 notches but its worn off! as you can see a faint mark where it used to be...
look at the CW straight on to the teeth or post a picture up. its normally plain as day!
milko96
05-06-10, 09:19 PM
I'll get a pic 2moro...
But diff is in the f15 box now and seems to work....
http://homepage.ntlworld.com/garyc/boxcode.jpg
right dod, the pinion gear is the one on the main cluster, the big one above the bearing on the right hand side in the first pic.
your final drive is the pinion and the big gear on the diff.
the inside of the casing in the second to last pic is your 5th gear
your 4th pic, they relate to the cluster
Burgo, many many thanks. Rep added.
I'm going to disassemble a diff so I can be 100% sure I know whats what.
Also, diff replacement, how do you know when you've tightened the diff enough? (sorry, I dont know the right name for the Castle nut thing)
This Website (http://slindborg.hostei.com/) might help you with deciding what box and FD you want to run,
just input your rev limiter, tyre size, gearbox and FD and it'll show you your speed in each gear
edit: or just look in stuarts sig!
Burgo, many many thanks. Rep added.
I'm going to disassemble a diff so I can be 100% sure I know whats what.
Also, diff replacement, how do you know when you've tightened the diff enough? (sorry, I dont know the right name for the Castle nut thing)
have a read of the F13 FD swap guide ;)
but in short, do the nut up till the diff wont turn, then back it off till the diff will turn reasonably freely
here some info a nova gte box is the same as 1200 corsa box the gearing i use is a corsa cluster and a 4.1 diff u beat most things of the traffic lights lol
Whats the 4.1 diff, an F13 item yeah?
thay come in f10 and 13 box u find 4.1 in 1400cc corsa mk 3 1400 astra 1.3 and 1.4 mk 2 astra some mk 1 astra n cavs and in 1.2 ,1.3and 1.4 novas
Bin the text typing.
Dod, the 4.18 FD is not for big blocks lol
NP. Its just that I'm currently building an F20. DO the clusters look similar, as per the FD Swap guide?
nope
The F20 and F16 have the pinon cast/welded/glued on the output shaft, so its a full output shaft strip and rebuild to swap the FD on a big block box.
Thank you! I'll get an F13 cluster pic'd tomorrow and added to the FD Change article.
Feel free to delete my last post in there to keep the place a little tidier.
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