Garage Takai

Got bored yesterday while waiting for parts to arrive, so instead of tidying the garage ahead of the engine swap, i welded in the reinforcement plates to the subframe:

Take one set of Spec Miata subframe gussets:

[img]http://images.plebeians.net/i.php?/upload/2019/06/06/20190606173241-fa14971d-xl.jpg[/img]

Line up:

[img]http://images.plebeians.net/i.php?/upload/2019/06/06/20190606173138-84db057c-xl.jpg[/img]

And weld:

[img]http://images.plebeians.net/_data/i/upload/2019/06/06/20190606173204-275c47d8-xl.jpg[/img]

Also, take this as a lesson of why not to build engines when doped up on Codral from a sinus infection. What is wrong here:

[img]http://images.plebeians.net/i.php?/upload/2019/06/06/20190606173259-7053dcaf-xl.jpg[/img]

So the MX5 is the first turbo install I have done where its not factory replacement or completely and entirely compromised by packaging, and i generally have a reasonable amount of time on my hands to get little things sorted (yay for no race schedule).

On all the previous cars (even the factory stuff) the water ports have been relatively horizontal, and I have followed suit for other turbo conversions.

However, reading this Garrett whitepaper (mirrored on GCG) [url]https://gcg.com.au/component/rsticketspro/view-article/18-water-cooled-turbos-they-need-water[/url]
they suggest a 20° clock with the inlet down and the outlet up. But also recommend an uphill pipe from the outlet to somewhere else in the engine to enable thermal siphoning after shutdown.

[img]http://gcg.com.au/images/water_p7.jpg[/img]

On the MX5 this is a problem, as the high pressure inlet sources for the turbo are all in the head, and higher than the turbo. Conversely, all the return locations are low in the block or the mixer.

Originally i was planning on just running the high pressure side out of the thermostat spacer at the back of the head, where the heater core comes out. Or as another guy down here has done, inline with the heater core:

[img]https://i.imgur.com/w2TPhkc.jpg[/img]

But that puts the inlet side at 20° elevated, rather than on a decline, and from this graph is more than somewhat undesirable:

[img]http://gcg.com.au/images/water_p8.jpg[/img]

How much am I overthinking this? Just put it in horizontal and leave it be?

Started working out a place for the intercooler and oil cooler, and I think it will end up with them stacked in front of the radiator. A little less than ideal, but nowhere else really works for packaging.

Used it as an opportunity to practice more on the TIG:

[img]http://images.plebeians.net/_data/i/upload/2019/05/25/20190525005709-fa133f9e-xl.jpg[/img]

Made up a long bracket to go between the upper AC mounting holes:

[img]http://images.plebeians.net/_data/i/upload/2019/05/25/20190525005735-bbdc22b3-xl.jpg[/img]

FG intercooler fits well in there now:

[img]http://images.plebeians.net/_data/i/upload/2019/05/25/20190525005727-68707ef2-xl.jpg[/img]

Although im still considering getting a shorter and wider core to mount in the air stream some more. Perhaps something like this at 500x230mm:

[img]https://i.ebayimg.com/images/g/vy0AAOSwFeNcw8Dj/s-l1600.jpg[/img]

Typical that just after I pick up the block i come down sick and am out of action for a week or so. Crawled out of bed today and was feeling a touch better, so started pottering around building the engine.

First up was doing all the calcs for the piston/rod/pin combos:

[img]http://images.plebeians.net/i.php?/upload/2019/05/23/20190523050531-3e3b1bd9-xl.jpg[/img]

Then file fit all the rings, which mercifully didnt need much more than a touch on the linisher.

Add one set of ACL race bearings:

[img]http://images.plebeians.net/_data/i/upload/2019/05/23/20190523050523-b9f234c1-xl.jpg[/img]

[img]http://images.plebeians.net/i.php?/upload/2019/05/23/20190523050514-b652dd86-xl.jpg[/img]

Add rings and spin them all around to different parts of the piston, and compress:

[img]http://images.plebeians.net/i.php?/upload/2019/05/23/20190523050504-3274377c-xl.jpg[/img]

Insert into block:

[img]http://images.plebeians.net/i.php?/upload/2019/05/23/20190523050359-8b808809-xl.jpg[/img]

Check bearing clearances with Plastigage… then find out that your plastigage has gone hard, and go buy ACL Flexigauge. Check bearing clearances with Flexigauge:

[img]http://images.plebeians.net/i.php?/upload/2019/05/23/20190523050409-f0e42e62-xl.jpg[/img]

Rinse and repeat 4 times while fielding calls from OS and small children, and you get this:

[img]http://images.plebeians.net/i.php?/upload/2019/05/23/20190523050431-d1a2741e-xl.jpg[/img]

[img]http://images.plebeians.net/_data/i/upload/2019/05/23/20190523050456-2a51c8a3-xl.jpg[/img]

Subsequently realise that you cant remember aligning the rings on piston 2, and so remove that to check… thankfully i had actually done it.

CSH time: When i was in high school a kid a couple of grades above got a Datto 1200 for his birthday and proceeded to do it up, so that he could drive it to the Year 12 formal. When it came down to the wire he started it up and it was spewing smoke out the exhaust. Nevertheless he drove it to school proudly.
What went wrong? Well he was a little bit OCD with the car, and so lined up all of the piston ring gaps on the pistons…. :knock:
Taught me that you shouldnt line up piston ring gaps, even before i had built an engine.

Anyway, now waiting for replacement valve springs to come for the head, and then I should be able to screw that together and start thinking about closing up the engine.