Woodsport longer 5th gear

[Clarky_X]

So here is an update from my efforts today. Unfortunately I didn't manage to get very far.

I got the fork and hub off, but when I came to use my 3 arm puller to get the next bit off it wouldn't fit. I have a Teng tool 4" puller and the arms wouldn't get up inside the inner wheel arch. The one used in the linked knowledge base article was obviously a 3" puller. So now I have to see if I can get some 3" arms for mine.

I tried and tried and tried, in both 2 and 3 arm configuration, but it seems that it does need to be done with a 3 arm puller because the synchro ring has some teeth missing in 3 places around the edge and therefore it gives enough space to get the puller arm in. When trying it in 2 arm puller, I could only get the tiniest bit of the puller on one arm and when tightening it just kept popping off.

So I got fed up and cold and put it all back together, filled with new Millers fully synthetic oil and took it out for a test drive. All the gears worked, 5th still popped out, so I started to give it some, and now 5th pops out under acceleration too. bu88er, guess I won't be overtaking for a week then.

Incidentally, it's worth pointing out that I didn't buy the hub that the selector fork goes on, and it does seem to have a few burs on some of the teeth, but looking at the new one in Lauren's pics at trackdayqueen, it looks like the teeth on the inside edge are supposed to have a chamfer to them, so I don't know if mine needs replacing or not.

Regarding the fork, the new corolla one I bought and the MR2 one I took out of the box look identical with the exception that a couple of lugs are missing on the new one, but they don't connect to anything, so I could probably use either.

[Clarky_X]

Couple of images of the 2 forks

[Clarky_X]

£63 for the Corolla sleeve (goes on the selector fork)
£25 for a 3" 3 jaw puller

Fingers crossed. Again.

[Clarky_X]

OK so I'm a berk, re-reading the instructions today when I had another crack at this I noticed that the instruction did state to use a 3" puller anyway. Anyway, I had my puller to hand and got the box drained and opened, fork off, started pulling the hub off, but in the mean time, Bolton Bill had asked me how many teeth the new gears from Toyota had on them. I'd replied before I started the job this morning, they are 31 and 38. While I'd been busy under the car, Bill had replied and said they were standard MR2 gears, so would be no change in the revs. So I counted the teeth on the gears in the box and sure enough, 31 and 38 teeth. Bummer.

A massive thanks goes out to Bill for stopping me before I fitted anything, so hopefully I can exchange the new bits for the different sizes.

Bill will hopefully have an update for us in a week or so when he's checked out the gears from other cars. Looks like we're looking at Carina gears at the moment, to get the ratio desired (0.725) we need teeth of 29 and 40.

The distance between the shaft centres is 68mm

Bill, feel free to post when you have an update. I'll await your call.

[PW@Woodsport]

Yes you must count teeth and do the maths with any new gear conversion, i had to do this with the Mk2 NA 5th gear upgrade, it took me several attempts to find the correct parts and numbers, each time buying a gearbox just to count teeth on its 5th cogs.

Does this mean the original part numbers i researched do not have the correct tooth count? or did Toyota supply the wrong parts?

[Clarky_X]

Could be either Paul, cos I gave Toyota the original part no.s from this thread but Toyota said they were old so gave me the new numbers. After much banter about what car it was going on and what car the gears came from they eventually went back to the new no.s they'd given for the original parts. Bill downloaded a document of all Toyota gear boxes, listing all the ratios and I think all the teeth because Bill said he searched them all to see which teeth arrangement got closest to the required ratio rather than just hoping there was a box with that ratio in it.

[bill hulme]

Hi I have a spare mk1 gearbox with the 5th gears removed
I have measured the centres today and they are 70mm between
the to shafts, I have had the covers of a lot of gearboxes at a scrap yard
and most are the same as the mk1 ie 31/38 teeth Im hoping to find a 29/40 to get the right ratio.
The gearboxes that have .725 ratio as Paul says are the C51 & C53 they
both have .725 ratio on 5th gear, But it could change with the engine size
The 1.8 7afe engine is basically the same as the the 4age but with a
longer stroke,
I am lead to believe that the Carina E 1.8 1992to1996 my have the correct gears,
I will hopefully be looking a one later this week, I will keep you posted,
As a matter of interest the following gearboxes have a 5th gear ratio
of .725 are C57 C58 C151 C153 C155 There is a 6 SPEED BOX with 6th Gear of .725 that's a C63 But on all these boxes the centres could be
different.
bill.

[bill hulme]

I found and fitted the .725 ratio gears today 29/40 teeth,
I was told they are from a Carina E 1.8 I removed the gears at the scrap yard, and fitted them this afternoon I only had to change the gears
all the other bits are the same,
well done to Paul Woods for this great posting
doing a Lakes run on Sunday to test it out.
Bill.

[PW@Woodsport]

Great stuff Bill, i knew the gears existed but the fact they work with the stock synchro hub and selector fork is a massive bonus, well done on proving the theory, that paves the way for others to follow our collective great work, which is what it's all about

[bill hulme]

Well, this is the gear the MK1 should always should have had,
At 70 mph (tom tom) the revs have dropped by approximately 450 rpm
to put it into prospective run at 70 for one hour you save 27,000 rpm,
you still use the 5th gear at all speeds as normal,
All I can say is Yes its put a very big smile on my face.
Its well worth all the time and effort to do this modification,
Bill.

[PW@Woodsport]

Good stuff Bill, i have gone back to post number 5 of this thread and checked my part numbers that i listed are also for the Carina E, they are, so these are the part numbers if anyone wants to walk straight into Toyota and get brand new gears....

Ok all wrapped up in 20 minutes, if you go to toyota and order the following gears...

33428-12050 -5th driven
33036-12051 -5th gear

They are the extended 0.725:1 gear set that will fit a mk1 gearbox.The only thing that is unknown is wether the synchro on fifth is compatible between the two but im betting it will be, at least for the later C52 box anyway.

[Clarky_X]

Ordered bits, should be in Wed. pick up Sat, I will then take the other gears back and double check the diameters and teeth. Fingers crossed they get the right bits in. I made it clear I needed 29 and 40 teeth.

So next question, what ratio do we need to drop by 800 revs. And is there a gear that would suit the box? 450 rev drop from my current box would be 70 at 3150rpm. That would be about the same as my son's 1.4 206. My wife's Lucida 2.2D is 2800@70.

[PW@Woodsport]

There are no other ratios available from the Toyota parts bin that will drop it further, it would have to be custom made gears after that.

[PW@Woodsport]

Just spoken to Bill, and it appears my original part numbers are for a different Carina E that might not have the correct tooth count, that is only a "might", it could be Toyota have used the same ratio on both models.

For now this is the exact part number set that Bill has back referenced with Toyota from the car at the scrapyard he found the actual gears from, so using its chassis number Toyota gave him these numbers which must be trusted ahead of my numbers (even though i suspect they may be the same ratio)

5th driven- 33428-12100 - £88.19 plus Vat
5th gear- 33036-12160 - £115 plus Vat

Please use only the above numbers if doing this mod until my original numbers can also be verified as correct or not.

Sincere thanks to Bill for this new info.

[crazybrightman]

this is a very interesting thread! having spent all of sunday rolling round on the floor fitting a new gearbox as i only had 4 gears (plus the clutch was gone aswell) i now have the new box in and its nodding well in 5th and feels very poor when selecting 5th so its not going to last long! as im heading to the ring in 3 weeks id like the idea of a longer 5th gear plus one that isn't about to give up!
now as im not one to spend a fortune on bits you could get second hand any idea what model and year carina these bits came out of? infact would it also have the same gears on the celica with the 7afe engine?

[bill hulme]

You will find that I posted that the Carina E the gears are from are,
1996/97 1.8 7 afe, it has a C51 gearbox I have spent days opening the the back cover of Toyota gearboxes, to find the right one and counting the number of teeth,
This was the only one with the right number 29/40 to give 0.725 ratio,
You could go to Toyota and ask them to see if the reference numbers
correspond on the car that you fancy,
Bill.

[Gad]

Hum, how tricky a task is swapping the gears over? My fifths been popping out for a while now and it's getting a little old, if I'm going to have to sort it at some point this sounds like an interesting option...

[bill hulme]

With the new gears in hand, it takes 5 to 6 hours and the right tools to
do the conversion, just changing the gears will not stop it popping out,
of 5th gear.
bill.

[Gad]

I know but it looks like I'd be in the right general vicinity to pop the cog off if I were DIYing the fifth gear fix.
Maybe I'll give it a shot when I'm feeling a little more flush with cash to buy the bits.

[bill hulme]

WOODSPORT 5th GEAR CONVERSION
Following an article by Paul Woods about a 5th gear upgrade for a MR2Mk1, I have now managed to find the right gears to complete the conversion. These referance numbers are from a Carina E 1.8 1996/97. I gave Toyota the chassis number of this car, and these are the gear numbers they provided, with the current prices.
5th driven- 33428-12100 - £88.19 plus Vat (29 teeth)
5th gear- 33036-12160 - £115 plus Vat (40 teeth)
I searched through lots of gear boxes from scrapped cars and eventually I found one with 29/40 teeth on the gears.
The car on which I eventually found the gears was a Carina E 1.8 Reg R701GFV The 1800 was only made for about 2 years (1996 to 1997 approx). If you find one of these cars, be sure to take the back cover off the box so that you can count the gears before purchasing. I found several gearboxes that looked the same but contained different gears. (Toyota do not put a reference type on the gear box to show whether it is a C51, C52, or C53 etc. My gears came from a C51, which I only know because this was the gearbox registered with the car.)
The gears are very tight to remove from the shafts, and you will need gear/bearing pullers to do this. A three-legged puller would work for withdrawing the syncromesh mechanism which is very tight on the splines. The main nut on the drive shaft needs a 27mm socket to undo it. Turning this nut just turns both gears, so you will need to jam the two gears together. I used a piece of V pulley belt end on, letting it jam between the gears while loosening the nut. With enough pressure you should be able to persuade the nut to ride over the indent that secures the nut in place.
Next remove the circlip at the front of the synchromesh operating mechanism that holds it in place. The gear at the back of this mechanism is on needle roller bearings in 2 halves and slides off with the hand. You will now need a different puller to withdraw the main drive gear, ensuring that this engages in the rim on the top of the gear. Positioning the puller under the teeth will usually result in damaging the teeth. On my puller I had to grind the left hand side to miss the the other shaft.
When you start the conversion, (assuming you are working with the gearbox in situ) you will need to do the following:
Jack up and support the car with axle stands so that you can then use the jack to support the gearbox.
Drain off gear oil
With the engine and gearbox supported, undo and remove the two centre engine supports
Then undo the support on the gearbox end.
Lower the jack gradually an inch or two to give full access to the end of the gearbox and remove the 9 bolts (12mm deep socket). Then use a hammer to remove the end cover, by hitting the protruding lugs
Remove the selector fork with its activation ring (10mm spanner)
Re-assembly is the reverse of these steps. Replacing the gears will require a fair amount of force i.e a drift and hammer or a deep socket for them to be properly located. It may it advisable to purchase a new locking nut (27mm) from Toyota (£4.80), since it has probably been damaged when it was removed.
If you have any questions please either telephone (01204... 578147) or email me at bill.hulme@(take this bit out)ntlworld.com
This took me 6 hours to complete. Don't forget to refill the box. It is a well worthwhile conversion, reducing the top gear revs by at least 450 rpm at 70 mph (27000 revs per hour) and is still usable as a normal 5th gear.
I must emphasise that this is merely a personal account of the steps I took to convert my gearbox, and I cannot be held responsible for any consequences of your following the same process.
Bill Hulme