Tranny go boom

[FE3-323]

dun dun dun

just to clarify ferdi i wasn't second guessing your work.
I hope you can find some resolve with a kia case & ring gear setup

[ftjandra]

just to clarify ferdi i wasn't second guessing your work.

Oh, I know. So, I decided to break out the cracked part completely just to see how much material there is to play with if I were to machine out part of it to replace it with a steel insert. Well, in some areas the wall narrows to less than 3mm, so a steel insert similar to the one I put in on the 5th gear end is out of the question, unless it's only 1mm thick...











Oh, and to answer the previous question of whether it made any funny noises prior to breaking, the answer is no. I had already used this tranny on the same track once before for an entire day with absolutely no problems (except for my brakes). It's a small 1.35mile motorcycle track that has no hard barriers for you to hit. You reach ~100-110mph and are always in 3rd or 4th gear.



--Ferdi

[Lex]

Ferdi, on that track, what kind of intake air temperatures and coolant temperatures are you seeing? Also what was the ambient temperature that day?

[wheresthericego]

damn thats crazy

[edumspeed]

Ouch! Dead trans suck BIG time.

[ftjandra]

Ferdi, on that track, what kind of intake air temperatures and coolant temperatures are you seeing? Also what was the ambient temperature that day?

Ambient temps were in the 80's, but I did not bring my tuning laptop with me because it doesn't hold a charge and I didn't want to bring the inverter and have it flying around in the car. The Haltech doesn't like usb->serial converters so my new laptop is no good. But, I did just order an expresscard serial card for my new laptop, so we'll see how that goes.

The coolant temps were 200-210°F with the oil being about 20°F higher. Cruising on the highway, coolant temps are 185-195°F.

--Ferdi

[FE3-323]

how much clearance in the bellhousing exactly do you have around that area ferdi??

[trailrider098]

AHHHH... my Quaife!!! i knew what your engine would do to that tranny.
i would make sure that you clean out the inside of the LSD REALLY good too. i heard that the gears in a zx2 are slightly stronger, you could use the final drive gears from that but it will change your overall gearing.

or go big and get this custom gearset http://www.albinsgear.com.au/images/.../mazda_323.pdf

[ftjandra]

AHHHH... my Quaife!!! i knew what your engine would do to that tranny.
i would make sure that you clean out the inside of the LSD REALLY good too. i heard that the gears in a zx2 are slightly stronger, you could use the final drive gears from that but it will change your overall gearing.

or go big and get this custom gearset http://www.albinsgear.com.au/images/.../mazda_323.pdf

Yeah, straight-cut gears would remove the axial forces and should help the case hold together. Any idea how the Albins gear set compares to the ones by PAR? That would be a lot of money though and you still end up with a weak tranny case. But, short of converting to a box from another car, I guess that's the only option.

--Ferdi

[ftjandra]

how much clearance in the bellhousing exactly do you have around that area ferdi??

You mean in the clutch cavity? A rough estimate is that I could weld in maybe 1/4" thick braces behind that 'cup' before it would hit the clutch pressure plate, so not much room.

--Ferdi

[MD323]

i have a kia bellhousing and gearset (the trans is already apart awaiting me to rebuild it all). if you want any of it shoot me a PM and we can work out something.

[ftjandra]

Mazda/Kia comparison pics

So, I sourced me a Kia tranny today (I still plan on buying yours too, MD323) and the differences in the bellhousings are huge. Whoever said that there are only minute differences is crazy... The pinion gear is wider and the way Kia made that work is by moving the bearing 'cup' (the part that broke off on mine) further down towards the clutch pressure plate. I was planning on welding in some reinforcing ribs behind the cup, but the clearance now to the pressure plate is most likely too small for that. There is a lot of extra material in the Kia casting next to the 'cup' that should allow for much more side force of the secondary shaft. I was also planning to weld in some reinforcing ribs there, but that's not necessary anymore now.

--Ferdi

[FE3-323]

holy awesome pictures ferdi!!!!! way to go

[therieldeal]

damn! i NEED to get myself a kia gearbox!

ferdi, could you be so kind as to waste a few mins of your life counting teeth on the kia gearset? i'm mostly interested in the 3rd and 4th gear ratios... 1st and 2nd will be the same as the mazda gearbox (all g series are 3.31 and 1.83), and 5th is easy to change.

[jitb37]

nice...finnally comparison pics!