MS3X MPi Turbo Tuning
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and some wear on no3. piston

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

Ooof a bit of detonation there!

New Year update...

Engine rebuilt, injectors swapped out to DEKA 850cc. Car running... sort of.

I think I'm running into low PW issues (was always going to be a risk).

See MSExtra post linked and comment there with specifics to the low RPM misfire.

https://www.msextra.com/forums/viewtopic.ph...=599358#p599358


To top it all off, the driveshaft has popped out of engagement with the gearbox whilst driving this evening. Hoping it's simply that it didn't go back together and click the circlip in place when I assembled it, and nothing else is the matter.

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

Very impressive build mate, i love that manifold arrangement looks awsome..
Great work mate

Cheers. It’s testing my resolve though. Gearbox has shat itself again. Seems this time it is lay shaft related.

I’ve got whirring in 1st and it pops out of reverse. Another engine out job!

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

Oh no how un lucky, i have to admit im a little worried about my gear box taking a shit when mines tuned althou i was going to go a sensible 10 psi for now..

Do they do up graded stronger gear boxes |?

I already learned that used metro HLE gear sets can’t take the torque. Rebuilt that and put in the Minispares helical set, some updated drop gears, new layshaft and bearings. Not sure yet what’s caused this. I wasn’t giving it much (like 2psi under 4000rpm) because I’ve not mapped it enough yet.

Hypothesis from Guessworks is the retainer plate in the layshaft.

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

Have you checked the layshaft retainer plate end of the layshaft in the casing for vertical play?
Ive found on a few casings that have had some abuse that this hole goes out of round and the shaft floats up and down.
To check I clamped some bar stock across the block to box flange and used a mag' base DTI on the shaft to measure.

Edited by shane on 14th Mar, 2024.