Daffy's SE

hks_kansei · Postby **hks_kansei** » Sat Dec 01, 2018 10:53 am

Nicely done.

One thing with that bracket, is it rubber mounted or just full metal?

Without the flex you'll still want to allow for movement, since the engine/gearbox will still be shifting when on the move.
Normally the hangers allow for that movement (or a flex join), but yeah, I would have thought that hard mounting it to the body would make it a lot more likely to crack a weld, or snap a stud.

Of course, if it's mounted to the gearbox and not the crossmember then never mind.

Daffy · Postby **Daffy** » Sat Dec 01, 2018 2:37 pm

hks_kansei wrote:Nicely done.

One thing with that bracket, is it rubber mounted or just full metal?

Sorry, forgot to include a pic of the mount.... some of the new noises may be just because of the new bits- I’m thinking if it doesn’t let up in the next few weeks we may have to recheck the bearings, early days yet, but so far the new setup feels great :mrgreen:

hks_kansei · Postby **hks_kansei** » Sat Dec 01, 2018 2:47 pm

Ah cool.

Yeah looked like it was attached to the subframe in the first pic.

JBT · Postby **JBT** » Sat Dec 01, 2018 7:20 pm

This is an epic build Daffy. :shock:

greenMachine · Postby **greenMachine** » Mon Dec 03, 2018 10:42 am

ManiacLachy wrote:Daffy, you should share this over at miataturbo.net as well. They love new information about installs, and yours is very interesting because it's an RHD car, and you've used an M gearbox.

Can't wait to see this thing rip!

Seconding this! I can see you have registered, don't be shy now ... :wink:

By all means post in the thread linked below, but I am sure a build thread would be welcomed there! Especially the M box and RHD aspects.

For those who haven't read them yet, this MTnet thread discusses the kit install, and there is also the KMiata vendor thread.

:mrgreen:

Daffy · Postby **Daffy** » Mon Dec 03, 2018 6:42 pm

greenMachine wrote:
ManiacLachy wrote:Daffy, you should share this over at miataturbo.net as well. They love new information about installs, and yours is very interesting because it's an RHD car, and you've used an M gearbox.

Can't wait to see this thing rip!

Seconding this! I can see you have registered, don't be shy now ...

The story of the Problem Child on miataturbo will be a bit of copy and paste, but I will work on a worthwhile read, it will be up soon (mx5cartalk is still home :mrgreen:

), meantime....... I’ll be getting a Holden mount to lessen the new setup stiffness of the absolute rock solid Kmiata gearbox mount to eliminate some of the cabin noise, but at this stage, the BMW gearbox transplant is F****** AWESOME. I’ve had the past few (enjoyable) days to put it through its paces and I have to say, it is outstanding. The cost is up there, no doubt- but the thought of not having to revisit driveline issues and realise the full worth of the Problem Child’s full power is well worth it. I intend to hold on to the Child for a long time- so for me, it’s money well spent. I’ll post more (video pics etc soon enough) this car of mine makes me smile, it thrills me and the joy I get out of driving it makes the expense so worth the while :mrgreen:

KevGoat · Postby **KevGoat** » Mon Dec 03, 2018 9:01 pm

Hell of a way to fix the 6 speed 2nd gear crunch!!

Love the work! Looks like you have a great mechanic there too.

Sent from my SM-G930F using Tapatalk

ManiacLachy · Postby **ManiacLachy** » Tue Dec 04, 2018 7:41 am

Glad to hear it's performing well. How does the clutch feel after you old heavy duty unit in the SE 6-speed? And, did you guys get K-Miata's driveshaft, or did you source one locally?

Daffy · Postby **Daffy** » Tue Dec 04, 2018 11:24 pm

The clutch definitely feels a bit lighter (though unsprung, I’m looking at ways to reduce the idle chatter at the moment), but Not forgetting that the Jim Berry custom clutch (up for sale shortly) is 3800lbs of clamp! The drive shaft is the Kmiata heavy duty V8 roadster one, and a bit heavier/thicker than the standard one. 2 pic’s pre paint with a steel drink bottle for a size reference and after paint just before install.

P.s KevGoat, mechanic Daz is the true brains behind this build, a great mechanic he definitely is :mrgreen:

ManiacLachy · Postby **ManiacLachy** » Mon Dec 10, 2018 3:47 pm

Greg at thecarpassionchannel on youtube just released his k-miata BMW trans install video. I haven't watched it yet, but I do enjoy his videos, great details. You'll have to turn up the boost to match his 415whp though :mrgreen:

https://www.thecarpassionchannel.com/getrag-swap

Daffy · Postby **Daffy** » Tue Dec 11, 2018 1:31 pm

ManiacLachy wrote:........ You'll have to turn up the boost to match his 415whp though

I seen a few of his YouTube vids during the gearbox reworking, very informative! A few more drives and more info from me shortly (still waiting on getting the gear to have the speedo back). As for the boost, early next year, like all of us after the Christmas feasting, its going to get fatter by a few more pounds :wink:

Daffy · Postby **Daffy** » Sat Dec 29, 2018 8:08 pm

Ok, so I’ve been told to torsen diff is good for up to 500rwhp.................. my problem child has ABSOLUTELY destroyed the SE torsen diff...........
Getrag upgrade to the rescue

Red_Bullet · Postby **Red_Bullet** » Sat Dec 29, 2018 9:27 pm

Might have been cheaper to buy a BMW or Porsche in the first instance. :shock:

bruce · Postby **bruce** » Sun Dec 30, 2018 2:28 pm

It's the usual - pass the power onto the next thing to break. Engine>Gearbox>Diff. Next you will have to tub it for traction.

Daffy · Postby **Daffy** » Sun Dec 30, 2018 7:17 pm

bruce wrote:It's the usual - pass the power onto the next thing to break. Engine>Gearbox>Diff. Next you will have to tub it for traction.

Don’t tempt me :lol:

3 weeks on with the Kmiata kit BMW 6 speed gearbox swap, here’s my rundown.
Prior to the Problem Child’s excellent effort at mercilessly destroying the torsen diff and its mounting yesterday, there was some good driving had with the new BMW 6 speed over the past 3 odd weeks; so here is the rundown.
The highway run had the rpm sitting on 3100 @110kmh, 2800 @kmh100 in 6th- lower rpm than the Aisin 6 speed.
City driving seen fuel consumption about the same as the original 6 speed.
The Kmiata kit has made for a far more rigid chassis, which combined with the new box and clutch has slightly increased NVH, most notable in slowing through downshifting changes.
The Kmiata short shifter setup is very mechanical and direct, the synchro’s engage smoothly and quick, it feels great :mrgreen:

.
The new flywheel is almost half the weight of the one I had in paired up to Jim Berry’s custom clutch, so that combined with much more direct driveline, NitroDann hotside engine mount and majorly increased chassis bracing sees much, much less drive train power loss, so much so that is why I believe the proof is evident in how the diff couldn’t hold out as well as snapping the drivers side mounting arm like a twig (there’s enough ways of bracing up the mounting arm available, so that was my bad for not doing that right at the start instead of waiting till I get the new speedo setup in. :shock:

)
So my initial impression of the swap is that it is all I expected, the gearbox is smooth and strong, the clutch feels light and easy, the chassis is massively more rigid, and there is much, MUCH more power getting to the back wheels (only 3 short weeks for the diff and its mounting let go! :shock:

)
More to come when the Getrag diff goes in.

Meanwhile, a couple of pics if the new set up and the diff’s death!