I know it's not turbo'd yet, but I think you may still find it interesting.



Scott Siegel (Tuner @ Subaru of Gwinnett, and owner Siegel Racing) offered up his 1990 Spec Miata as a test platform for something we've been working on here, and more specifically for a dyno session as the loaner car I've got is leaking a bit of oil at the moment. He's been racing in Spec but hasn't had the time lately so he's going to go turbo, a la MegaSquirt. He called me Monday night and had an opening Tuesday. I came out and we hooked the car up on the dyno and did a few baseline pulls on the stock ECU. Then we advanced the timing to 14 degrees base timing and did another couple baseline pulls on the stock ECU which netted the best power we were able to get from it. I wanted to compare the best the MS could do with the best the stocker could do, not some skewed 8 degrees of timing versus a perfectly dialed in map to make it look spectacular. Keep in mind stock timing for a manual is 10 degrees and going from 10-14 degrees makes a little difference on these cars when N/A, so if you're running stock timing you'd see 'slightly' bigger gains.

Everything was done on 93 octane pump gas.

Next comes the MegaSquirt-- I spent about 20 minutes installing it, we set the base timing and started dialing it in. We steady state tuned both the fuel and then the ignition map, then we started the ramp runs to dial in WOT. Long story short... 8ft/lbs-tq gains in the low rev range, 2-4 everywhere else. 95ft/lbs peak tq versus just under 91 on the stocker. As for WHP, 1-5 whp gain everywhere in the rev range, from idle to redline, with a 5whp increase at peak. 105 versus 100 on the stocker.

You'll notice on the chart a dip at 4500rpm... what you're really seeing there is not a dip, but a big spike just before that at 3700rpm that makes it look like a dip afterwards. Scott had seen this on other Miatas and thought nothing of it because of that. At any rate later in the day we pulled off the AFM to see what kind of difference it would make... Wow... Let's just say you're going to want to pull off your AFM. First off that 3700 torque peak goes away the second you pull it off and turns into a nice linear torque curve up to the real peak at 5700. If you like that first bump that may sound bad at first, but your torque everywhere else, particularly down low just off idle just JUMPS up a few more points and it stays higher across the board. That's going to do a TON more for the overall performance of the car than that wide spike at 3700 that quickly disappears. I didn't grab a chart of this because we didn't tune it in and it would need to be tuned for since the torque spike disappearing caused a big rich spot in that area of the map where we had tuned for that torque spike at 3700. I'll go back and tune another map for that soon. Regardless of it getting a bit rich at 3700 though I drove home in the loaner Miata with the AFM removed on our new tune (yes I had to take the ECU back out of Scott's Miata for now, he gets one in a couple of weeks), and it's night and day different from before-- it's not quite like my turbo MR2 mind you , but compared to the stock ECU this thing really moves now...


Here's the chart of the stock ECU at 14 degrees base timing (best case scenario) versus the MS dialed in:

 

nice dude that is sweet hopefully soon i will be able to post some results of MS Vs WI bandaid stock ecu system. this looks encouraging do you have maps available for the tune on your site? My MS will have a base tune but i would be interested to see where you guys tweaked and how far etc. To see what i do now and how much leeway i could get away with best case scenario. MS is the Cheapest product on the market and has been for a while but it seems cheap does not mean low quality in this case.

 

That's cool. Its about time someone in the MS world took a real interest in the Miata.

I remember driving mine dead stock but with the MS in and it felt much more lively. If I got a second miata, I'd have to ms it and remove the AFM at the very least.

 

We'll be glad to take that interest... in fact, take a look at who won this auction that just ended a few minutes ago.

http://cgi.ebay.com/ebaymotors/ws/eB...m=200093596744

Now... time to go schedule a flight to Ft. Lauderdale!

 

looks real clean.

 

<-- Anxiously awaiting more continued updates!

 

not a bad vehicle the HT is nice if you wanna sell it off lemme know dad wants one.

 

I'll probably hang on to the HT for now, down the road who knows, I'll wait and see if I use it or not... I fly down tomorrow morning to drive it back. Not wasting any time here .

 

I wonder if you could market a DIYautotune Miata PnP MS to somebody like Begi...

 

Dude a PNP vendor would be so hot. they would decimate all with there features and price point.

 

Clean. Made the longnose cutoff as well, I had to go double check :gay:

Dyno results very interesting. Props for doing it.

 

I hadn't checked yet... just did myself though and you're right it's a bignose- Bonus!

 

I thought about BEGI, they're pretty tightly attached to the XCEED though, time will tell-- I may still talk to them. We may be able to work with each other on some stuff... I'm thinking our car will be used for a 'Turbo Miata Cookbook' of sorts, with local easy dyno access, we'll see just what it takes to build it up a bit at a time. Most likely starting with a Greddy kit.

 

wow this is really cool

 

You can always borrow my car if you need to, once I have some break-in miles on the clutch. It's already greddy already.
I'm in the Hamilton Mill area, just a few exits north of you up 85.

If I ever get my Link back from FM, it could be cool to do a head to head.

 

I'd offer up my '93 if you need. I'm in Smyrna.

 

If you ever want to do some '99 testing i'm game. I'm running a '97 CAS.
I come to atlanta pretty frequently.

 

sorry to be a ricer... but where can I get those mazda stickers?

 

I am estimating an extra 5whp going from the MAF to a MAP system with a CAI.

How much was the gain from stock timing to 14* on the stock ecu?

 

I'm not sure where Scott got the stickers-- I'll try and remember to ask...

10* to 14* on the stocker was something like 2-3whp peak IIRC. I didn't save the chart or look at it super close.