Completely Safe Setup

[Race Grandpa]

Since I have had to spend a lot of money to fix the problems that have resulted from two shops not tuning the engine the correctly, I would like your opinions on the following:

What should I do to assure that I do not have any detonation. I have a J&S Safeguard. However, I understand that it does not make the adjustments after detonation begins. I would like to get Tom's timing card. However, I have promised my wife that I will not spend any more money - except for maybe the new air intake system.

I understand that the risk comes from the A/F setup.

So with all of that said

1) With the Safeguard what A/F setting would assure me that I have NO problems.

2) Without the Safeguard what A/F setting would assure me that I have NO problems. (I may sell the Safeguard to make my wife feel better.)

Although it is no longer an issue, what do you think my rwhp be with each of these two changes.

THANKS

[Race Grandpa]

Also, I have a brand new engine with 800 miles.

I mistated the issue with the Safeguard. It does not begin to adjust until the pinging starts.

[Tom @ Fast Forward]

The cheapest thing to do is pull a couple degrees of timing. It might cost a few WHP but it will make it safe. If I remember correctly, when the last engine went, they had pulled around 4 degrees. That should have made it very safe from ping. It was the 13:1 A/F that they tuned for that did it in, I believe.

I will probably catch a lot of hell for saying this but knock sensors and controls are a bandaid. They are re-active rather than pro-active. They sense knock and pull timing. That means the knock took place and the corrected on the next revolution of the engine. Too late IMHO. The best way is to pull timing in those areas that you find most likely to create knock and avoid it in the first place. The second problem is that the knock sensors have a hard time sensing the difference between knock and engine noise. In the 05, we found that Mazda gave up at high RPM and turned the knock system off. My guess is that they decided they could not tell the difference between knock and lifters/cams/cam gears, etc. When we put the timing card on and pulled 2 degrees above 5000 RPM, it would run on the worst 91 octane fuel we could find. In your case, you can pul the 2 degrees by simply adjusting the CAS on the back of the engine. Granted, that will cost you some loss of WHP at low RPM but probably worth the insurance. Like I said, they pulled 4* on your engine before and that didn't help but death was from a different cause.

We did find on the dyno that my 99 was almost impervious to timing retard in the mid range (torque peak). We could pull several degrees with no WHP loss in that area. Above 5000, on the other hand, it was very sensitive to timing retard. In any case, I can run the 130mm pulley on my 99 now with a couple degrees of mid and high RPM retard on pretty poor 91 octane. No low end loss of power.

There is no such thing as completely safe when it comes to making power and pushing the car. I have heard of a couple cases of destroyed stock engines.

[Race Grandpa]

Tom,

I am not sure that they adjusted the timing. If that was shown on the dyno charts, I can not verify as I destroyed the dyno charts. Hell, they could have adjusted it to Spec Miata setting. So I will make sure sure that this is taken care off.

I COMPLETELY AGREE WITH YOU AS TO LACK OF PROTECTION from the knock controls and sensors. In the 200 miles I put on the car after the SC install, I never heard any pinging. When I was on the track with the instructor I did not hear it ping. By the time the instructor heard the first ping the engine was toast.

Corky's states in his book that it can happen on the first ping.

Also, as to A/F I think you said it would be safer between 11 or 11.5. Is that correct? What about taking the A/F lower?

Paul

[Tom @ Fast Forward]

They told me that they had pulled 4* when they tuned it. Hmm, as they were into normally aspirated Miatas, I wonder if he meant they ADDED 4*?

Yes, I agree, it CAN happen on the first ping. You can also have a lot of ping with no harm. My 99 has suffered ping on numerous occassions on the dyno when testing new features/devices/pulleys. It now has 135,000+ miles and has had 200+WHP since 30,000 miles. Back when I had the WI, it would run out at the worst times. Like canyon carving in heated battle or teaching a Camero what life was like in the fast lane on an on-ramp. It is the main reason I don't like WI. HOwever, a recent leakdown test was all above 85% and compression cold/dry was 160-170.

The 94-97 engines seem to like the 11.5:1 range more than 12:1 but I would go no richer than 11:1 as that will only waste fuel and not help much.

[Race Grandpa]

Tom,

The tuner had the A/F set to between 13.2 to 14.3 .

:2guns: :stuart:

Paul

[Tom @ Fast Forward]

I know. I still have the dyno charts. :hammer:

[Race Grandpa]

To claify my comment below. It did not happen with the J&S Safeguard.

Tom,
I COMPLETELY AGREE WITH YOU AS TO LACK OF PROTECTION from the knock controls and sensors. In the 200 miles I put on the car after the SC install, I never heard any pinging. When I was on the track with the instructor I did not hear it ping. By the time the instructor heard the first ping the engine was toast.

Paul

[Tom @ Fast Forward]

Just a guess but I'll bet the knocking sounds you heard came after the piston melted. No knock sensor or timing card in the world would save an engine running 10+ PSI boost at 13-14 A/F.