Maxx Mazda's 2011 Build Thread

Miguel how do we get those cups?? Also Maxx you should try PAR double synchro with custom gear ratios.

Pretty soon i will start a GI thread to see how many people wants to get rid of breaking gears. what PAR did is not funtional since all they did was putting the bearings on separate Sleeves. that does nothing it will expand and flex under heavy loads and high oil temps. my special brace have been storied and engineered by a wrc mechanic friend of mine and will trully prevent oem, and aftermarket gear sets
from not being engaged all the time preventing the 2 towers of gears to separate creating what we all know it happends teeth damage. teeth breaks because they are not fully engaged. if they separate just a bit kaboon.. Helical cut gears are whole lot stronger than Straight cut but the handicap is they tend to separate from each other do to the angle they are made. if you keep all teeth in and fully engaged they are stronger than straight cut but you need to help the transmission case to not flex under heavy loads. sorry my english is kind of limited to explain all my friend have. hes a retired world rallye car mechanic. now he owns his own shop and all he does is racing and rally car builds.
 
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Miguel can you put me in touch with the guy who designed that? I'd like to either buy one or get the schematic from him so I can have one made.
 
Slightly in defense of the par cups being a two piece assembly... Essentially they accomplish the same thing since each component is bolted and seated into a tight tolerance bore independently they can only flex as much as the inner most bolt hole spacing would allow unless the case was ripped in half.

I think this is to allow some type of allowance under high heat expansion where the aluminum casing wouldn't be the same as the steel plate... causing bearing damge??
 
you would think this could help the stock trans as well


Of course Ryan this is like a J&S Safeguard but for the transmission. this will help and prevent any gear sets to stay engaged and alive from failure its easy to break the tips of the teeths if they are not completely in if you know what i mran
 
Slightly in defense of the par cups being a two piece assembly... Essentially they accomplish the same thing since each component is bolted and seated into a tight tolerance bore independently they can only flex as much as the inner most bolt hole spacing would allow unless the case was ripped in half.

I think this is to allow some type of allowance under high heat expansion where the aluminum casing wouldn't be the same as the steel plate... causing bearing damge??

being 2 separate sleeves it will still flex. theres people who had them installed along with straight cut and still broke gears.. a solid single piece will not under any circunstance flex causing the input and output shaft to sepatate..
 
Miguel, For the third time can you please put me in touch with this guy? I want either an engineering schematic, or I'd like to buy one directly.
 
Miguel, For the third time can you please put me in touch with this guy? I want either an engineering schematic, or I'd like to buy one directly.

dont worry im working on prices since ill be soon selling these.. ill get back soon with info. this guy its on some rallies on belgium
 
Im still not entirely convinced that the flex of the case itself is 100% to blame here. I was looking at the transmission today while I was cleaning it up in the varsol tank, and I got to thinking. The ends of the shafts use tapered roller bearings that must be shimmed precisely to avoid axial movement. I always shim my trans on the very tight side of Mazda spec for this reason.

Im going to look at converting the tapered bearings to heavy duty ball bearings instead. This would eliminate any possibility of side movement of the shafts and differential (provided im able to find precisely sized bearings.)

I got the idea from all the motorcycles I rebuild. Each and every one of them uses ball bearings in the transmission and engine bottom end, and after I researched the idea a bit I discovered that high HP Honda guys have been swapping to ball bearings for awhile for the same reason. I have a local supplier here with a nearly infinite supply of industrial ball bearings and seals, so finding the correct sizes should be relatively easy.

I still haven't ruled out case flex entirely, I'll do some more research on that front as well.
 
Sub'd

The time, money, and engineering you put into your car is astonishing. I would love to have a car just like yours. With the amount of work you put into your car, I would be better off building a cloning machine and running your car through it.
 
Tapered roller bearings are good at two things. They handle axial loads, as well as thrust loads. (The gears coming apart, and the tendency of the gears to also push "up" under high loads.)

Ball bearings, and straight roller bearings that matter are not designed for high thrust loads. This video illustrates what happens with helical gears when a high amount of resistance is applied. FF to 1:40


I've rebuilt more than half a dozen motorcycle transmissions, all use ball bearings. However, all also have straight cut gears. I'm not about to buy a full $7000 PAR gearbox, nor do I want to simply "drop in" say 3rd and 4th gear. I want to come up with a reliable, affordable solution to this damn transmission. Some are quick to point the finger at the actual integrity of the metal that makes up the gears. I disagree with this, Focus even did a hardness test on stock and GTX gears back in the day. The GTX gears were harder, but its not like either were made of spaghetti.

No, the problem lies with the fact that when stuffing 3-4 times the designed horsepower through the transmission, the design simply can't handle it, and that's what I've set out to remedy. I've decided that I WILL NOT RUN straight cut gears. Some may scoff at this, but this is not a "stripped down" race car. I want to keep my A/C, have a stereo, power steering, and a comfortable interior so I can take my family on a sunday drive through the mountains without my ears ringing. I guess you can say my tastes have "matured" somewhat, and I value an ounce of practicality along with performance.

The main issue here (C6 Z06 guys struggle with this too) is that the damn gears pull apart under that much load. The trick now is to come up with a fix for it. The PAR reinforcement cups in my opinion don't do much. They reinforce the area directly around the bearing race, but they don't add much to the case itself as far as structural rigidity. I came across this one piece plate that looks like it does a much better job:

img2811dq.jpg


img2810d.jpg


Might look into something like this. Then again, what do you do about the other side of the shafts? The output shaft is pretty well supported, but I'd like to reinforce that pinion shaft somehow. The research continues...
 
I posted to the original poster of that pic mentioning that part of the reason behind the 2 piece bearing reinforcement is likely to allow for some thermal expansion which would be very different from the tranny case material. Each part of the cup is seated into a bore which holds its center... unless the case cracked in half
 
one of my audi friends was telling me they have the same problems with the a4. he was explaining that they use a similar brace to the one pictured above but more rigid, yet they lose 5th gear. I havent researched it myself but thought I'd put a bug in your ear
 
^^^ I'm also curious. And I plan on drilling/tapping my intake mani for the temp sensor as well for my KL swap but couldn't find much info on anyone else doing it that way. Everyone else just puts it in the air intake piping.
 

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