I will eventually do a manifold but not now.

 

How much weight came off that crank?

 

I really should have weighed it because I knew everyone would ask. I dont know. 25% maybe more?

If I didnt mention it this is a mystery engine. Came from a very well known serious engine builder, Supposedly had 10 hours on it in an IPRA car (Improved production racing association) it was a lucky dip, we had no idea that we would find this crank, the sump baffle, Ti retainers the amazing port work etc etc. We just knew it was build by a well respected race engine guy for a series that allows a lot of mods.

It was purchased on ebay for super super cheap, we just tore it down measured everything and put it back together with what it needed, which was bearings, we honed and decked the block and decked the head. CC'd it for comp, chose a head gasket (Maruha .080), took the sharp edges off the pistons and put it together. Added the bigger turbo, modded the mani for ext gate etc and we chose to use an external pressure control valve to attempt to alleviate oil pump failure. The oil pump valve is chocked closed.

Dann

 

What made you choose that gasket? Did you take into account the squish zone alteration (i.e. is the block decked down ~.040" to put the squish area measurement back to where it needs to be)? .080" squish is approximately 2x what is ideal, and that kind of squish will reduce power, reduce mixture homogeneity, and promote detonation.

 

The compression was too high. it doesnt have .080 squish because the piston is about .040 above deck height after machining. Im definately not pretending to be an engine expert, Ive had 2 engine experts involved in putting it back together right, and we changed things like rings gaps and stuff to suit. Ive built a dozen or more engines but Ive never done anything as silly as this so I got a lot of advice. I hope it all works out.

Its a bit 'suck it and see' but its an 11.5:1 engine that will get 20 or 30psi thrown at it, so the whole thing is suck it and see, really.

Dann

 

inlet or exhaust Leafy?

and what is z series?

 

Mx5-kiwi, here is the thread I believe leafy is referring to:

https://www.miataturbo.net/build-thr...e-build-62722/

 

both. Look at dem intake ports in that thread glade linked, ******* super bike mega ports.

 

 

When I read "knife-edge" on the previous page I nearly laughed. But now I see it was actually bull-nosed on the leading edge and knife'ed on the trailing edge. I approve.

 

getting close.

















The cooler piping I redid so that stock undertray fits without the piping stickout out and big holes cut in it. Happy so far.
Unfortunately the filter will have to go right on the end of the turbo..

Dann

 

Put a metal plate over the freeze plug in the front of the head before it blows out.

 

Thank you .
Its glued in with aviation sealant.

Why does this one have more of a chance of coming out when the dozen other welsh plugs stay in?

Cheers,
Dann

 

If it's happened once to someone else 5 years ago, it was enough for me to spend 5 minutes tracing the bottom edge of the old neck and copying out of .5" bar.

NOTE: you need to curve the edges or it won't fit.

 

But every car on the planet has a dozen or more welsh plugs just tapped in and glued, What makes this one different?

Dann

 

Because iron expands less than aluminum. I've seen that exact plug pop out of that exact place multiple times. It's not if, it's when.

 

Okay, cheers.

Dann

 

Is the port on the head machined different for the miata bps vs the fwd bp? The fwd pbs have just a freeze plug there and nothing else, iirc.

 

This thing is ALMOST together. I'll get some pics up in the next hour or 2.

Still needs vac hoses, Mac valve mounted. Oil cooler, filter and pressure reg hoses done.. And the rest of the front main duct. Waiting on some sheets to be guillotined for us.

Probably only have time to do half a tune and put 15 psi in for now.
Edit: because trying to hit the track this weekend.

 

Man, I don't mean to be a dick but I'm not sure I'd ever use your shop after a comment like that. I'm not sure how things work in Austria but we generally expect people to finish jobs like this once they are paid for.