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Re: 1991 Miata #20 Hunchback

Posted: Sun Feb 26, 2017 12:32 am
by AndreyB
[video][/video]

Re: 1991 Miata #20 Hunchback

Posted: Sun Feb 26, 2017 1:17 am
by stefanst
Running the harness externally would be a pretty cool look. Kind of like a Borg theme. "We are the rusefi. You will be assimilated. Resistance is futile."

Re: 1991 Miata #20 Hunchback

Posted: Sun Mar 05, 2017 12:26 am
by AndreyB
Great wrenching session today! Helps to have all the random parts on the shelve - NA6 to NB2 conversion ask for a 99 fuel rail - we have it, conversion asks for a 94 alternator - we have it!

Axles, ppf, last two control arms, struts are now on the car. There is a hope to start the engine next weekend!

Re: 1991 Miata #20 Hunchback

Posted: Sun Mar 05, 2017 3:06 pm
by stefanst
Awesome!
So do I understand that right and the engine and harness are in? Pictures?

Re: 1991 Miata #20 Hunchback

Posted: Sun Mar 05, 2017 7:01 pm
by AndreyB
stefanst wrote:Awesome!
So do I understand that right and the engine and harness are in? Pictures?
Nope, need a couple of vacuum plugs and coolant reroute installed and transmission mounted. Kind of very close to go into the car.

Re: 1991 Miata #20 Hunchback

Posted: Sun Mar 05, 2017 7:50 pm
by stefanst
So you're converting to a return-style fuel system?
I like the idea, since dead-headed fuel systems are an atrocity. But I don't think your stock ECU will still work well after the conversion. It relies on constant fuel pressure at the rail for calculations, Now you have changing pressure.

Re: 1991 Miata #20 Hunchback

Posted: Sat Mar 25, 2017 9:41 pm
by AndreyB
Started VVT in NA car! Currenly on stock ECU, hopefully tomorrow will make progress with harness and run on rusEfi.

[video][/video]

Re: 1991 Miata #20 Hunchback

Posted: Sat Mar 25, 2017 11:04 pm
by stefanst
Image

Re: 1991 Miata #20 Hunchback

Posted: Sat Apr 08, 2017 9:02 pm
by AndreyB
Harness is now inside the cabin, car goes to a shop for exhaust and alighment. Next weekend is road testing, if things go nicely it goes to a dyno in two weeks.

[video][/video]

[video][/video]

Re: 1991 Miata #20 Hunchback

Posted: Tue Apr 11, 2017 1:30 pm
by stefanst
stefanst wrote:So you're converting to a return-style fuel system?
I like the idea, since dead-headed fuel systems are an atrocity. But I don't think your stock ECU will still work well after the conversion. It relies on constant fuel pressure at the rail for calculations, Now you have changing pressure.
I'm not sure that we had an answer to this yet...

Re: 1991 Miata #20 Hunchback

Posted: Tue Apr 11, 2017 2:12 pm
by AndreyB
Yes return-style fuel system now. It helped that we had 91, 94 parts and 99 parts readily available :)

I was trying to add a fuel pressure gauge but got the wrong diameter adapter. Will report how would stock ECU perform AFR-wise, thank you for the hint to look out for that.

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 14, 2017 5:29 am
by AndreyB
Green race car uses pieces of 2002 engine harness - complete under-the-hood piece and a part of main harness.

There are minor differences between 2002 and 2003 wiring (red test mule car is 2003), I am planning a universal Frankenso harness so that same Frankenso could be used on both 2002 and 2003. Technically there is probably an option to modify the 2002 harness to match 2003 but I'd rather not do that.

2002 ECU and main relay:
Main relay is controlled by ignition switch (this is different from 2003 where ECU controls main relay via 3H).
Nothing on 4S (4S is ignition power source on 2003).
ECU is powered from main relay via 4AF (this is different from 2003 where ECU is powered via 4S)

2003 ECU and main relay:
In start or run ECU is powered from Engine Fuse 15A via 4S. (This is different from 2002 - nothing on 4S in 2002)
ECU controls main relay via 3H. (This is different from 2002 - nothing on 3H in 2002)
ECU gets +12v from main relay output 4AF which is used as +12v source for VVT (4D) and IAC (2P).

For my universal 2002/2003 harness I plan a little toggle switch between 4S and 4AF:
Toggle switch ON would feed Franenso on 4S wire on 2002.
Toggle switch OFF would disconnect ignition lock +12v from main relay +12v in order to properly operate on 2003.

See also http://rusefi.com/wiki/index.php?title=Vehicle:Mazda_Miata_2002
See also http://rusefi.com/wiki/index.php?title=Vehicle:Mazda_Miata_2003


Three cabin fuses are needed to run 2002 engine - cabin fuse box is replaced by a couple in-line fuse holders. Main relay box is used as is. 2002 harness ground goes to top of intake close to throttle body, 2002 harness power is taken from main kill switch. There is a small toggle switch replacing ignition key - 1991 ignition key is not used at all.

Starter and alternator are still on 1991 harness, alternator is not controlled by rusEfi.

I will borrow Stefan's idea of soldering fly-back IAC and VVT diodes right to the connector adapter board - the pins to connect are conveniently located close to each other.

Electrical checklist:
  • Brake lights
  • running lights
  • Hazards
  • Blinkers
  • low-beam head lights
  • radiator fan
  • wipers
  • gauge backlight
  • fuel gauge
  • fuel pump (requires main relay)
  • engine starts & runs
  • alternator charges
  • dummy light
  • tachometer
  • oil pressure gauge
  • CLT gauge
  • fuel gauge
  • WBO power
  • camera power supply
  • cool shirt power

Re: 1991 Miata #20 Hunchback

Posted: Mon Apr 24, 2017 7:10 pm
by stefanst
Is the car going on a dyno any time soon?
I'm curious for obvious reasons....

Re: 1991 Miata #20 Hunchback

Posted: Mon Apr 24, 2017 7:50 pm
by AndreyB
Little unplanned holes are in the way. Also we've probably made the mistake of removing these low-end butterflies from the intake. Long story short I am currently in PANIC MODE - race is in 18 days, car is not ready. More details later tonight :)

Re: 1991 Miata #20 Hunchback

Posted: Mon Apr 24, 2017 7:52 pm
by stefanst
You can borrow my VTCS intake.
I also have a spare VICS intake sitting in a box. Can deliver.

Re: 1991 Miata #20 Hunchback

Posted: Tue Apr 25, 2017 3:29 am
by AndreyB

Re: 1991 Miata #20 Hunchback

Posted: Thu Apr 27, 2017 1:58 am
by AndreyB
Things are starting to look better!

Tach works, temp gauge works! Laptop mount is mostly ready for road tuning, still need to wire warning light and figure out why VVT does not work.

[video]https://www.youtube.com/watch?v=owg1SdErA7I[/video]

Re: 1991 Miata #20 Hunchback

Posted: Thu Apr 27, 2017 7:34 pm
by stefanst
You could run stock ECU in parallel, stock taking care of the VVT and rusefi running fuel and spark. A bit complex, but.....

Re: 1991 Miata #20 Hunchback

Posted: Thu Apr 27, 2017 7:45 pm
by AndreyB
stefanst wrote:A bit complex, but.....
C'mon, you cannot be serious! That's... Not the right way! We know two rusEfi boards have controlled VVT on two different cars, should not be much different on the 3rd car.

Re: 1991 Miata #20 Hunchback

Posted: Thu Apr 27, 2017 7:55 pm
by stefanst
russian wrote:C'mon, you cannot be serious! That's... Not the right way! We know two rusEfi boards have controlled VVT on two different cars, should not be much different on the 3rd car.
And yet you fail :mrgreen: so far....
More news tonight?

Re: 1991 Miata #20 Hunchback

Posted: Thu Apr 27, 2017 10:58 pm
by kb1gtt
stefanst wrote:And yet you fail
I don't know why he's having problems, he's got a Gen2 engine harness spliced with a Gen3 engine harness, which is then spliced with a Gen1 body harness. I know how to fix it, get a ford harness and add that :) I think you can do your own version of monkeys writing Shakespeare, but with harnesses and engines.

Good luck. I'm sure you have a minor electrical problem. Probably just a wire crossed or something like that. I'm sure you'll find the issue in that spaghetti and then you'll be good. Happy hunting.

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 2:59 am
by AndreyB
It was diode soldered not where it should be soldered, I got myself confused with the pinout. Notes at the bottom of http://rusefi.com/wiki/index.php?title=Vehicle:Mazda_Miata_2003 are corrected now and VVT works. And rusEfi now knows AFR, and warning light works just needs to be soldered. Little steps every day :)

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 3:05 am
by AndreyB
Oh, and you can see WHP predictions at the bottom. Why wants to make their prediction? :)

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 9:46 am
by kb1gtt
Some one has been after me about SI vs ANSI units, so....

100 kW.

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 1:06 pm
by stefanst
92kW

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 1:11 pm
by puff
Is it an educated guess? or just a shot in the dark?

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 1:17 pm
by stefanst
Stock is rated at 140hp at the crank. Deduct 10% for drivetrain loss gets you 126. That's 94kW. Deduct 2kW for 'random' spark tune and you get 92kW. Which presumably makes it an educated guess, but it could still be waaaaaaay off. I'm hoping for more :)

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 2:43 pm
by puff
But stock means injection times designed mainly for ecology and pollution control. This one aims for more power (otherwise, why would you want to remove stock ecu?)
So, I'd say 102kW, and it's more of a random shot :lol: - since I still don't know how much more power you can get off stock engine with a custom ECU...

Re: 1991 Miata #20 Hunchback

Posted: Fri Apr 28, 2017 10:28 pm
by kb1gtt
Don't forget detonation pressures make higher hp. It does not have knock so detonation pressures would be done to detect.

Re: 1991 Miata #20 Hunchback

Posted: Sun Apr 30, 2017 2:05 am
by AndreyB
30 highway miles with TS auto-tune. Car is hellasweet! https://svn.code.sf.net/p/rusefi/code/misc/logs/1991_miata_hunchback/20170429_vvt_first_highway.7z

Monday is dyno day.