OMS CF09 TT4
Turbo Mini Forums

mmmm, could be due to a sticky valve, or could be header design, some of those headers now being longer might try to pull the peak down hence the increase below and decreas above peak, i'd look at closing the LSA upa couple of degrees and see what happens

the other thing is, it could have changed the tune a fair bit, causing a hot valve?

Thanks Joe.

The fuelling was corrected on the RR so the tune was ok.

there is currently no adjustment on the cams to make small changes unfortunately.

I'm thinking of fitting the head from the Z1000, which has larger ports and valves. Maybe the 100hp Z750 head is at it's limit.

John - Mini is still around. Last time we used it it broke. It will come out again at some point.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

Finally got the new vinyl on. Quite pleased with it.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

Looks mint!

If something is worth doing, it's worth doing half of.

sticking valve could well cause that , but i would have thought it would have made a noise in the exhaust .

manifold looks to be a bit too v shaped where the pipes meet the turbo plate , maybe those two cyl air streams are hitting each other .

valve sticking due to heat swelling it up in the guide ? perhaps hone guide or run richer to cool it .

also retarded timing would make the valve head hotter .


regards
robert

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Thanks Robert. Thinking back, you could occasionally hear the valve stick, but I wasn't sure what it was at the time.

It runs lots of advance. I actually think it was a lack of oil that caused the valve failure.

As for power, the manifold is much nicer inside than the outside suggests. But there isn't a lot of room, so this is as good as it'll get.

The Z1000 head has larger ports and valves and is a straight swap (same cams) for the Z750. So that should help power at the top end.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk