Supertech 9.5:1 & DET - Should I be worried?
 

Hey guys, I am concerned.

I have some supertech pistons on the way and recalled a while back a discussion about det inducing pockets? And the possibility that the stock supertech piston could be fixed by carving out the thin lip around the valves. Would a machine shop be able to do this if requested?

Went through these threads:
https://www.miataturbo.net/engine-pe...onation-42072/
https://www.miataturbo.net/engine-pe...pistons-38232/

Found some photos..

ZX-Tex - Damaged Piston

'Carved' sorta like this but minus the det :bigtu:
https://www.miataturbo.net/attachmen...ine=1439500582


Mine 'should' look like these when they come in for 9.5:1
https://www.miataturbo.net/attachmen...ine=1353558912

https://www.miataturbo.net/attachmen...ine=1353558912


Cherry on top... :eggplant:

Stock MSM ECU has a BEGi reflash and on top of this is an XEDE.

I will be daily driving this vehicle to work. Not looking for ALLOFIT just yet, not going to see track time anytime soon but a few pulls on my way to work will definitely happen.
Shooting for 10psi with the gt2860 (for now).

ALSO! To minimize my chances of DET, should I let the reflashed ECU do it's thing and not tinker with the XEDE timing map? I understand the tuning aspect will have a huge part with DET but that is sorta out of my control. I'm perfectly fine with near stock timing if it reduces the probability of failure. Just need to pass emissions & get decent gas milage at this point.

Why are you building a 9.5:1 pump gas motor?

Why in the hell are you stacking an Xede on top of a reflashed ECU?

I told him this is a bad idea. At least twice via our PM convos

It came with the vehicle when purchased. Ive only recently found out everything I have (flashed ecu).

Trust me, I already know I should probably look for another msm stock ecu/immobilizer/msm injectors etc. Thats on the todo list, very limited with funds at the moment. :burncash:

Isn't stock at 9.5:1? Thought about attempting E85 later with a megasquirt.

Fingers are crossed the tuning can be managed, I intend on getting logs if possible and figuring this setup out on my own.

Until then, I'll try to stay out of boost.

I carved out those lips with a dremel tool, then polished, then re weighed them.

Your hole situation (that's the appropriate spelling for this app I think) is pretty unsafe though. If you don't have the cash for MS, how are you going to afford a new engine if gremlins show up? Just something to consider.
Check this out in a list format:

Hi compression
unknown tune on an uncontrollable computer
turbo capable of pretty big boost
your only car to get to work

FWIW, I had pretty bad knock on pump with 9.5:1 supertechs.
E85 seems to have solved that issue though.

Good to know with the dremel :bigtu:

Hole situation is correct. This vehicle experience has been a nightmare. :hatecat:

And you're correct if any 'new' gremlins show up, I'm screwed.

I didn't plan on doing a rebuild, my motor spun the #4 bearing on the crankshaft on the day of me picking it up from BEGi. Once the motor was apart, there was a lot more wear that just the failed bearing. Whoever had my car before drove it into the ground and autox it at one point. In some weird way, I'm glad the bearing failed now or I would of been down in the hole further if I took the vehicle back and it failed after my tuning mystery was solved. Mostly sticking with 9.5:1 CR to eliminate additional tuning.

The List so far:
Supertech 9.5:1 83.5mm | Wiseco 8350XX rings
H-Beam Manley rods
Clevite allthethings

And a used crankshaft from a car in california that was caught on fire :dunno:, according to the machine shop my crankshaft is a no go due to the #4 bearing failure.

As for my questions in bold, dremel approach is nice but I don't have access to doing this myself. I will try to find out from the machine shop. For avoiding DET with my aids, leave timing alone?

Interested in your tune, going to scan through your build thread now :bigtu:

I'm gonna go on record and repeat for the umpteenth time that I feel bad for you and this situation you got into with BEGi, but I really truly think that there is a really high probability that you're just digging a bigger "hole" by having one of the most unreliable and inconsistent companies known to mankind rebuild your engine, and then have one of the worst tuners I've ever heard of tune it, on a bunch of stacked together half band aid tuning solutions.

Seriously. I hope it works out, I really do, but I have a bad feeling about this.

Good luck man. I hope you get to finally enjoy your MSM soon after all these months of them screwing you over.