Let's do this again! NB this time!

I LIKEY!

clean miata is clean

New pictures


IMG_6970 by acedeuce802, on Flickr


IMG_6971 by acedeuce802, on Flickr


IMG_6964 by acedeuce802, on Flickr


IMG_6967 by acedeuce802, on Flickr


IMG_6988 by acedeuce802, on Flickr

Good looking car

Bought a Hard Dog Ace roll bar. Also bought an adjustable timing wheel, so I can advance the timing. I'm planning on buying a piggyback ECU from my friend so I can retune it. From what I've heard, the ECU tunes for 14.7 AFR up until 4000 rpm on Miatas, and tuning for 13 can net some huge gains in the low RPMs. Now I just need some time to install these things LOL.

what does advancing the timing do?

Advances the timing..... lol. It means that the spark plug fires earlier, as in, earlier before the piston reaches TDC (top dead center). Each engine setup (with given conditions ie: temperature) will have an optimal timing. Usually, OEM tunes will have a timing that is retarded (later in the combustion cycle), because the more retarded the timing is, the better emissions (until too much efficiency is lost). A basic way to tune for ignition timing is to keep advancing a degree. When the power starts to drop off, then go back to the last setting you had it at. If the motor starts to knock (pre-detonate), either back the timing off, or run a higher octane fuel. Repeat the process with the higher octane fuel.

Standalone ECU's will have the ability to advance and retard the timing on the computer, the piggyback system I am looking at can only retard, so you set the static timing more advanced, and retard from there if need be.

When running boost, the timing needs to be retarded to prevent knock. The more boost, the more retarded the timing should be. General rules are: hotter intake air, or more boost = retard timing. Cooler intake air will allow for advanced timing.

I'd imagine it would be super hard to tune for mbt without an egt gauge and spark control..no?

Not sure about the EGT gauge, but I will have spark control!

I thought you just said you can't advance spark timing, only retard?

nice input Adam i just learned something

That's why I just got the adjustable timing wheel. So, I'll set the base timing to like 4 degrees advanced, then I can retard from there. So, I can run 4 degrees advanced static, then pull back like 2 degrees at 3000 rpm, then 2 more at 5000 rpm or something like that, and at that point I'll be back to stock timing.

did you install the rollbar? get a set of unibits from harbor freight and one of those spring loaded punches. it will make the install much easier than using stupid drill bits.

retarding the timing is much safer than advancing it because the piston stroke is already going down. if you have it too advanced where it's before tdc the piston is on the upstroke.. that plus combustion pushing back against it leads to not happy engine parts.

xcoldricex wrote:

d if you have it too advanced where it's before tdc the piston is on the upstroke..

I've never worked on a car engine where the factory timing was at or after TDC. Once the air/fuel mix is ignited it does take a moment for the conflagration to reach the point where it will actually start to put pressure on the piston, so if you spark at exactly TDC the combustion will be too late.

The way Adam described it, it seems like his timing setup have static timing at 4 degrees before TDC and his ECU will retard the timing from there based on an RPM map.

yeah i understand. i was just stating in general since dani asked about timing.

oh i see. yes most cars are tuned to spark before tdc because the fuel/air mixture takes time to ignite and expand. i was just trying to get the point across that retarding is safer than advancing way too much.

xcoldricex wrote:

yeah i understand. i was just stating in general since dani asked about timing.

oh i see. yes most cars are tuned to spark before tdc because the fuel/air mixture takes time to ignite and expand. i was just trying to get the point across that retarding is safer than advancing way too much.

Yeah, just a miscommunication from terminology.

Turns out the rollbar is a Hard Bar Sport M1, so it won't work with my glass window... gonna try to sell it and get an M2.

Regarding timing, my stock timing is at 10 degrees BTDC, and I'm going to 12, people have safely gone to 14 still on 87 gasoline, but the high end power starts to drop off drastically. 12 is proven to be a safe setup on this engine. So, if I get the piggyback controller, I'll probably set the timing to 14, and back it off as the rpm's increase.

acedeuce802 wrote:

Turns out the rollbar is a Hard Bar Sport M1, so it won't work with my glass window... gonna try to sell it and get an M2.

Regarding timing, my stock timing is at 10 degrees BTDC, and I'm going to 12, people have safely gone to 14 still on 87 gasoline, but the high end power starts to drop off drastically. 12 is proven to be a safe setup on this engine. So, if I get the piggyback controller, I'll probably set the timing to 14, and back it off as the rpm's increase.

Being able to map it over the RPM band is the important part. Static timing cars are forced to compromise.

Egt starts dropping when detonation occurs.

Excited to see how much power you pick up!

xcoldricex wrote:

did you install the rollbar? get a set of unibits from harbor freight and one of those spring loaded punches. it will make the install much easier than using stupid drill bits.

retarding the timing is much safer than advancing it because the piston stroke is already going down. if you have it too advanced where it's before tdc the piston is on the upstroke.. that plus combustion pushing back against it leads to not happy engine parts.

Are these what you're talking about?

http://www.harborfreight.com/spring-loaded-center-punch-621.html

http://www.harborfreight.com/2-piece-titanium-nitride-coated-high-speed-steel-step-drills-96275.html

acedeuce802 wrote:

Turns out the rollbar is a Hard Bar Sport M1, so it won't work with my glass window... gonna try to sell it and get an M2.

Just ordered a HDHCHTDDM2

acedeuce802 wrote:

acedeuce802 wrote:

Turns out the rollbar is a Hard Bar Sport M1, so it won't work with my glass window... gonna try to sell it and get an M2.

Just ordered a HDHCHTDDM2

im going to assume thats the roll bar you need

Yes, hard dog, hard core, hard top, double diagonal M2. Basically the beefiest one made for an NB.