Nige's GT86

[GT86Jay 202]

On a stock engine how many miles should the plugs last?

 

The Toyota Service Sheet shows 60k and they're £13.71 each. Apparently the labour is included in the full 60k service. 

[Lauren 2259]

My plugs will need changing at my 60K service I'm on 52K+ at the moment. 

 

Service cost is £500 for that one. 

 

Whilst I appreciate it makes some sense to put these holes in, given the longetivity of the plugs, it doesn't make that much sense unless you're going to be changing them a lot more often. 

[Guest]

Absolutely right Lauren. I will need to be checking mine rather than changing them.

Today is a good day!! I got my Pistons, Rods and Sump in my grubby little hands and a call from Adrian to say my Turbo kit is in production and will leave the factory on Jan 12th.

[Guest]

So, onwards and upwards.. I've had confirmation that my ARP bolts and studs have left the USA and the Cusco Engine mounts and oil pump are on their way from Japan.

In the meantime, I thought I'd drop my gearbox to get the rest of the floor painted and also because I need to remove the front suspension before cutting the holes in the chassis rails. (The gearbox sits on the Xmember when the engine is removed, very handy)!! Anyway, I was very shocked to see yet more black particles on the magnetic drain plug and that the oil was grey. Remember, this oil has done 50 miles tops!!

"I'm going to strip this box and see what's going on" I thought...

So, here we have it, the internals of our GT86 BRZ Gearbox, and very nice it is too. In this pic we can see the two main shafts of the gearbox. The shaft on the right is the output shaft which goes straight to the prop shaft. The one next to it is the countershaft.

Here are the shafts removed as an assembly. Note there is no 6th gear on the countershaft, this is removed before the main case is split.

On the upper main shaft we can see the output going off to the left, and the input shaft is on the right. If we go from left to right on this shaft we can see 6th, 1st, 2nd, 3rd, 4th and Reverse gears respectively. When the input shaft is not engaged with the main shaft, ie:- not in 5th gear, it turns the countershaft which in turn drives all the other gears.

Here are the gears and shafts all stripped down.

So, what have I found.. nothing much really.. There are some sharp edges which could have been de-burred at the factory in reality, and some casting flash on the casings, other than that nothing? There were more metal filings here and there.I am going to chamfer the edges of the gears and perhaps get them super-finished as they're out.

The gearbox itself looks very tough, with strong selectors and big balls for selector engagement. I doubt we'll have much trouble with these jumping out of gear? The helix angle is fairly steep on all gears, which makes for a smooth quiet 'box, but does not lend itself to strength.

One would assume someone will come up with a straight cut gearset for this 'box in future as I cant see these gears lasting too long with aggressive changes and post 300hp mods. Has anyone found this gearboxes power ceiling yet?

[Guest]

Just had a knock on the door from Mr DHL delivery driver..

He brought me a little box, all the way from Japan!!

The box contained these..

They're Cusco engine mounts, very stiff little beggars. NVH and firmness are being increased again!!

I found them on Ebay at a great price..here http://www.ebay.co.uk/itm/281365383662?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[Guest]

So, the superfinishing of the main gears and shafts is done now... very shiny!!

The hubs and baulk rings are in today. All in all this process takes about 16 to 18 hours to do!! The polished surfaces of the teeth reduce friction, therefore lowering temperature and also help to make the shifts much smoother due to the polishing of the baulk rings and engagement teeth of the synchros. I also believe this will make the 'box a little tougher as all the stress raisers are gone?

[Pitman 188]

Have you polished the case as well, Nige?  Could you share some details of the superfinishing process?  Once I get my life sorted out, I have a gearbox (not GT86, but still Toyota  ) that could definitely do with the benefits you have listed.

[Guest]

Hi Dave,

 

I haven't polished the case, there would be no benefit other than cosmetic. Having said that, I will be removing all the rough cast areas just because it's apart.

 

The process basically entails placing the parts in a large rumbling machine, full of ceramic beads. They rub the surface for hours and hours, along with a very slightly abrasive paste to give the polished finish you see here. The metal removal is no more than a couple of microns, so all the push fits and clearances remain. This is all done by a race engine builder who happens to be a mate. He has been doing this and seeing benefits in engines, gearboxes and diffs for years.

[Pitman 188]

Thanks, Nige.

 

The reason why I asked if you had polished your case is that, in the picture above, the bell-housing looks like it has been polished.

 

Dave

[Lauren 2259]

Such impressive attention to detail! That would scare me taking a gearbox apart. 

 

Interestingly my gearbox is pretty smooth, though north of 52K miles certainly helps here. 

[Guest]

Thanks, Nige.

The reason why I asked if you had polished your case is that, in the picture above, the bell-housing looks like it has been polished.

Dave

Hi Dave,

Yeah, the bell housing is pretty nice, though the rest of the castings have spiders web finish inside and out in places? Obviously part of a modern casting procedure. It's funny, some areas of the engine are very smooth, looking like die cast, yet other areas on the same casting are definitly sand cast?

If love to see the process they use, I find this kind of stuff very interesting.

[Guest]

Such impressive attention to detail! That would scare me taking a gearbox apart.

Interestingly my gearbox is pretty smooth, though north of 52K miles certainly helps here.

Go on Lauren, give it a go, it's fun!!

[rob275 1817]

wouldn't mind giving it a go, but i'd rather have a spare gearbox in case I fudge something up  

[Mark@Abbey M/S 235]

Nothing on the motor is sand cast , too expensive to make stuff like this. Sand cast is normally for short production runs;

 

Modern items are pressure die cast , the spiders webs you say Nigel is where the casting cools off we have been told.

 

The spiders webs aren't a weak point on the castings.

 

Chemical polishing does work , better to do it to new parts thou as old parts have all ready been loaded and may off already re-work the material.

[Guest]

So, we have started cutting metal on this little car now.

As I stated in the beginning, this car will be a rocket bunny, so will be having very wide wheels front and rear, somewhere in the region of 9.5" front and 11" rear. The extension at the end of the sill gets in the way when you fit wheels this wide, so they need to be shortened..

Here's how I started..

Drill out the spot welds and remove the end panel..

Then mark up the line where the cut needs to be...

And cut...

To close it all up, I intend to reverse the end panel and swap sides, giving a smoother finish and less of a dirt trap...

I shall weld these in tomorrow hopefully?

[Keethos 842]

A question for you Nige, though it might be a lil early but will you be keeping the riveted look or will you cover them up on the body bunny panels? Also, will you be keeping the rear of the wide arches open or will you close them off?

[Guest]

At the moment I intend to keep the bolts exposed look, but that may change. The rear arches, and fronts will be closed off. I don't want road dirt getting into places it wasn't supposed to go.

[Bail 33]

I love this thread. That is all

[Guest]

Here's a little Sunday morning post for those who are browsing..

Have you ever wondered the best way to get around welding near plastic bits and wiring?? Take the plastic and wiring out!!

As you'll see, this is a little more involved than one might think at first..

Here we can see lots of the stuff that's just waiting to melt and go up in flames..

So, it all needs to be removed. There is a problem.. to remove the brake lines, the servo has to come out, so the clutch master may as well come out too,(Brake fluid is VERY flammable)

Then, to get the wiring out, you need to disconnect the engine loom from the interior, which means the dash has to come out...

So, while I'm at it, the support beam may as well come out so I can get the air con condenser out of the heater box..

And the heavy sound deadening can come out to allow me to seam weld the bulkhead without risk of fire..

Then.. we can remove the engine bay wiring loom...

Notice the holes in the rails for the plug access tubes, this is where the welding is to be done, but hey, I may as well seam weld the engine bay while I'm in there... After all the shell will be subjected to twice the power and torque it was designed for and the harder suspension...... that's just my excuse for playing "race car fabricator" lol

Keep watching for updates, this should be a lot of fun...

[Guest]

I've had to change my plans slightly.. the pressed steel end plate which I was going to weld in was so thin on the corners I decided to make some new end panels from 1mm sheet.

Here we can see my efforts just placed in the hole..

Then we can see how it looks all welded up.. please keep your pigeon sh1t jokes to yourselves..

And finally, with the welds polished back for a smooth appearance...

So, now we move on to the tubes and seam welding.. Thanks for looking in..

[Mark-in-Stoke 488]

More, more, more top thread !.

[Ade 517]

This thread is amazing. Keep up the good work Nige

[Guest]

Thanks Mark, glad you're enjoying watching me rip my car to pieces.. it's FUN!!!

[nikndel 509]

What type of welder are you using Nigel?

[Pitman 188]

I can only echo the posts above - without doubt my favorite thread on the internet at the moment!  Keep the posts coming, please