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M2cupcar's 1990 Mazda Mx-5 Miata FE3 Turbo (35th) 
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LQFP112 - Up with the play
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Yes- the stock oil pump had a shim added to it first time around. At 7k rpm with hot oil it was showing over 90psi. Hot idle was 15-20psi. This indicated on the stock pressure gauge. I can't tell you why I pulled the shim because I never had any issue with oiling or seals. Everything was fine and I had to mess with it. The Benz 123 oil cooler is a Behr tube and fin. Not the most efficient, but it fit my available space perfectly and was readily available for the nominal price of $40 delivered thank you eBay. FC Rx7 oil coolers are similar tube and fin, larger and designed to run width wise with the inlet/outlet on the same side for a dual pass. That is the grassroots go-to oil cooler for those that have the space for the price and greater capacity.

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90 Miata | 302rwhp @ 6450rpm | 281rwftlbs @ 4800rpm | FE-dohc 2.0L turbo


Tue Jul 05, 2016 7:31 pm
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So I have to ask, what oil are you running, exactly? And is this motor build on the loose side intentionally? I never put a gauge on the ute, but it clearly had solid oil pressure except when I ran it out while doing donuts and ran that big end :-D I guess what I mean is, how is your factory pump not good enough when mine was/is fine? Something is different.

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Tue Jul 05, 2016 11:00 pm
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LQFP112 - Up with the play
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Right now it has 10/40 Rotella synth in it. Which is what it's always had. The motor is an unopened honest to god Mazda FE3. Make that a JDM FE3. It was one of the clean ones too- no paste in the head to hold the cams and lifters in. :D What the gauge shows now is pretty typical to what a stock Miata shows on a B6/BP. But a common practice for Miata owners is to shim the oil pump when going turbo. Which is why I did it last time, which was the first time around on the turbo train. At this point I have yet to determine that my factory oil pump/pressure is inadequate and I hope not to.

Screen grab of a cold start to warmed up engine showing CHT:
Image

Does that not look like a rise in temp to the Tstat opening, the a repeat of rise/fall as the engine heats and then the fan cools?

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90 Miata | 302rwhp @ 6450rpm | 281rwftlbs @ 4800rpm | FE-dohc 2.0L turbo


Wed Jul 06, 2016 12:59 am
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It does, and because I saw your email first, my detailed reply is there. Feel free to quote most/all of it here if you like. :-)

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n00bs, do NOT PM or email tech questions! Use the forum!
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Wed Jul 06, 2016 2:21 am
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LQFP112 - Up with the play
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Quote:
Yep, your Tstat is clearly working perfectly! But you're generating too much heat at idle for the passive cooling of the setup. My truck is the same with the thick radiator, there is no airflow without the fan...

This is exactly how the first car's cooling system worked. Never overheated, but with everything crammed in such a small space and thick stack, the temp rose to fan trigger quickly in the summer heat when the car stopped moving.

Quote:
Your warm up curve needs to end by about 75C to not be enriching when the tstat is open which we must deem as "warm enough".

That makes perfect sense.

Quote:
Your idle is a tiny bit high at a bit over 1k, but I guess that's on purpose to assist with cold running, right? Cold right now of 28C and you have what appears to be unassisted 1070 RPM.

This ford throttle body came to me with a large hole in the throttle plate. Apparently this hole is typical for base idle and changes in size depending on which model car the throttle body comes in. This hole put my idle at nearly 2000 rpm fully closed. There was no removing the screws without grinding the ends off them- they looked pressed on the ends. I brazed the hole shut which dropped the idle to where it is now. But in the process there was enough heat to slightly warp the plate, so there's a throttle leak around body lip/flange when shut. If little pressure is applied to the plate it seal enough to where the engine will pull the idle valve open.

Image

Quote:
Lowering the RPM and getting back to stoich should make it a bit happier and cooler. Pull the warm up curve back just a little more, 100% by 75C (or lower if you want/can, sooner into stoich idle, the better, really, only add fuel where necessary to run acceptably)

I need to pick up another throttle body without a hole in it. They're dirt cheap since they came in so many different fords- typically around $25 delivered.

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90 Miata | 302rwhp @ 6450rpm | 281rwftlbs @ 4800rpm | FE-dohc 2.0L turbo


Wed Jul 06, 2016 1:43 pm
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OK, no big deal, but get it back to stoich, it's too lean at the moment, which could be contributing to the heating up thing. I did two screen shots for Rob in the email the quotes come from, so here they are:

http://stuff.fredcooke.com/RobsThermost ... anTemp.png
http://stuff.fredcooke.com/RobsIdleMayH ... chment.png

And inline, same order:

Image

Image

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DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!


Wed Jul 06, 2016 2:51 pm
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LQFP112 - Up with the play
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Yep- ford 65mm v8 TBs are cheap and plentiful:
Image
94 Crown Victoria / Grand Marquis appears to be one of the few with NO holes in the throttle plate.

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90 Miata | 302rwhp @ 6450rpm | 281rwftlbs @ 4800rpm | FE-dohc 2.0L turbo


Wed Jul 06, 2016 6:06 pm
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