NTS MX5 Build

[CTWV50]

Originally Posted by sven8t4

Hey Just a quick note I used to play with 850 T5's and my V70AWDr these original rubber mounts fail all the time on the T5's the poly bush variants are much much better.

Steve

Cool! LOL!

[Big Vern]

Originally Posted by CTWV50

Hmm, thanks for the costructive critisism, I'm only running a cheap 1.6 open diff atm so if it does fail with this design I'll upgrade to a torsen and rethink the design. I think most people will of thought about a solid mounting to the chassis but surely you would end up with alot of vibration through the chassis which would cause other reliability issues.

edit: Have you got any links BV for the failures on locostusa? What's your source for the westield miata issues?

Cheers

Chris

I have long suspected the westfield miata suffers chassis cracking because of solidly mounting the diff, but the sierra diff is solidly mounted and does not throw up any problems.
As said already your design shows you have been thinking about how to mount the mazda diff and the unusual problems its design has created.
Heavy duty engine mounts perhaps rally spec would get the job done.

I came across the problems with westfield miata when I strumbled across the build thread for the car flyin' miata built.
The others including the locostusa came yesterday when I did a google search for MX5 miata diff mount problems.

Sorry I didn't do any links to these sites I was just havin' a beer and surfin'

Well done TQ uk - I like the gold brace on your RX8/Current MX5 rear end. That would be a good way of dealing with the problem, maybe just use the rear 6-8inches of the power plant frame or a lazer cut and folded substitute. That brace would constrain the diff nose and assist the two mounts in the diff carrier.

BV

[jenks]

I think Big Vern and CTWV50 pretty much have it sussed... Mr Gibbs designed the framework of the seat back to soak up the torsional loads of the diff, so that's where we need to send them in this design too. If we can do that and get some vibration isolation (poly bushes) then it's win-win, jelly and icecream for everyone!

Does anybody have a 3d cad file of the Saturn chassis with a model of the diff in place? (SolidWorks, Inventor or the like)

I'm thinking of something along the lines of a bracket mounted at 90 degrees to the right-hand seatback upright then a mount along the lines of Skov's diff nose mount but with 2 polly mounts fixed a 90 degrees, spaced a good distance apart to spread the loads acting under tension and compression...

Skov's design looks really nicely engineered but the mounts will be under shear forces when they're designed for compression (and I think they're rubber)

http://1.bp.blogspot.com/-rANr4WQ7IX...unt_fitted.jpg

http://3.bp.blogspot.com/-MVpVJo0hIs...t_fitted_2.jpg

[Johno]

Well had a play about with the diff mounting today and managed to fit a welded frame to the nose of the diff and two rubber mounts.



Bit of a tight fit but it all goes in....just.....
Also fitted the spreader plate to one side of my diff bolted to my chassis bracket.



Obviously the spreader plate is in line with the bush and the spreader is at an angle to the diff housing. Does anybody know if this is the case on the MX5 or is the chassis mounting at an angle to run in line with the diff housing.

Johno

[Johno]

Well I guess it's pretty much covered by BV and Jenks.
I guess the difference between the Sierra diff and MX5 is the Sierra doesn't have arms sticking out both sides making any torque movement worse. Sodily mounting the front nose of the diff will only cause metal fatigue and fracture of the chassis sometime in the future. Mazda realised this and fitted a PPF as standard. Triangulation of the chassis will only make things worse resulting in a weld faiure along the HAZ of a weld.
I spoke to Nathan Sunday and the only reason the diff broke was because he forgot to fit the diff washers....LOL..
Ok he agrees the diff mounting below the diff wasn't upto the job but this didn't brake.
Basically if the front nose of the diff was to be solidy mounted as per Westfieid and others who grow onions then Mazda could have saved a lot of RD money.
Well just my thoughts I guess others will disagree........
But I look at it this way, if Mazda fitted it it's good enough for me...

Johno

[MarkB]

You do realise that IVA inspectors monitor forums like this

[CTWV50]

MarkB please get a life!

[MarkB]

Originally Posted by CTWV50

MarkB please get a life!

Ti's true, I'm wasting my time but then I call it irratainment as it makes me chuckle the things people do and how they do them. Sometimes I comment sometimes I just laugh.

[CTWV50]

What you're doing on this forum is nothing new to most people, it's quite clear you enjoy trolling this forum for your own reasons. I guess the best thing people can do is just ignore your posts as they really serve no useful purpose.

You may enjoy this little youtube video.

http://www.youtube.com/watch?v=HaMOcJfsksI

For anyone who doesn't know what Mr. MarkB and his aliases is up to....

http://en.wikipedia.org/wiki/Troll_(Internet)

[MarkB]

Originally Posted by CTWV50

What you're doing on this forum is nothing new to most people, it's quite clear you enjoy trolling this forum for your own reasons. I guess the best thing people can do is just ignore your posts as they really serve no useful purpose.

You may enjoy this little youtube video.

http://www.youtube.com/watch?v=HaMOcJfsksI

For anyone who doesn't know what Mr. MarkB and his aliases is up to....

http://en.wikipedia.org/wiki/Troll_(Internet)

Indeed I'm best ignored, I never listen to anything I say as it's 99% tripe