Important Warning

[Race Grandpa]

IMPORTANT WARNING
AVOID
DENOTATION & PRE-IGNITION

My Story
I have ruined two engines in the last 46 days due to detonation or pre-ignition

WHY ?
1) No one, including Tom & my Spec Miata shop, know why.
2) It was not because of poor engines as the first had 51,375 miles with good compression and the second had 55,125 miles with good compression.
3) I do not believe it was because of a poor tune-up on the dyno as the Spec Miata shop uses them all of time for the Pro Series
4) Neither time when it happened was I running over 6,000 RPM

So there is no answer.


What It Has Cost Me

A total of $8,000 plus another $837 (net after refunds) lost on 4 racing school over the last 3 months

My New Insurance

J&S Safeguard www.jandssafeguard.com

The insurance premium is only $450 for life.

YOU can not afford not to have it. :nono:

[Race Grandpa]

Each time after my engines failed I thought about selling the SC to get $$$ to replace the engines.

I did not do this as I new I would end up buying another FFS. It took me 12 months to save the $$$ to buy it. And I was not going to settle for something less.

Tom thanks for a great product. When I was on the track Tuesday I got up to 110 mph at 6,000 rpm. :biggrin: (Coldside with 110mm pulley and no other performance equipment.)

Now I just need to get that :biggrin: back again.

[Scuba Steve]

Very sorry to hear this, can you provide more information. I assume the A/F ratio had been dyno'ed or you had a wideband, correct?

Is there any more information you can provide? How do you know it was detonation that killed the motor? I'm not challenging you, just trying to get more info.

[Race Grandpa]

Very sorry to hear this, can you provide more information. I assume the A/F ratio had been dyno'ed or you had a wideband, correct?

Is there any more information you can provide? How do you know it was detonation that killed the motor? I'm not challenging you, just trying to get more info.

Scuba Steve

The A/F ratio was checked on the dyno and it checked out perfect. I do not have a wideband. I did not have the $$$. (Definitely do not have the $$$ now.)

The first time it happened I was on the interstate with the radio going. So I did not hear any pinging. I was in Portland at the time to run at PIR. So the car got towed to a Miata speciality shop and they said it was detonation. This was confirmed by the shop that I towed the car to in my town.

The second time it happened I was on the track and heard the pinging. I shut it down immediately after I heard the pinging, but it was too late. Interestingly or not so interestlngly, the oil pressure got up to 250!!!!

FUC******** :mad:

PS: The only "good" thing about the last experience was that my wife is out of town. If she knew what has happened, the SC and maybe the car would be sold by now. To avoid her seeing a check for all of this I took the $$$ out of my business account. I have never hidden anything from her as long as we have been married - but I have the need for speed.

[Race Grandpa]

Now that I think more about it I was only at 5,000 rpm. If I had only another 1/4, I think I would have been close to 145 mph. I wish I had a taller gear so I could cruise at 120 mph.

This straightaway was slightly downhill with big trees on each side of the road. At the end of the straight away you entered in to a blind hairpin with no runoff area. That is when you start praying to God.

Oh, on my way to the track I got picked up for going 80 mph in a 35 mph zone. It "only" cost me $450, which is minor compared to all of the $$$ I have gone through in my disastors.


Each time after my engines failed I thought about selling the SC to get $$$ to replace the engines.

I did not do this as I new I would end up buying another FFS. It took me 12 months to save the $$$ to buy it. And I was not going to settle for something less.

Tom thanks for a great product. When I was on the track Tuesday I got up to 110 mph at 6,000 rpm. :biggrin: (Coldside with 110mm pulley and no other performance equipment.)

Now I just need to get that :biggrin: back again.

[Tom @ Fast Forward]

Paul,

Carlo called me yesterday and we chatted for a good 30 minutes. I asked him if he had the dyno charts. He did and described to me and A/F curve that started off at ~12:1 and ended up in the 13s as it crossed 6000. Not exactly what I would call perfect A/F.

We discussed your fuel pump or FPR as the possible cause. I know the 96/97 can make sufficient fuel if the FPR is good as we could keep Dave's 97 around 10:1 if we needed after we replaced his FPR. Before that, we couldn't keep it below 13. If it was that lean on the dyno, there should have been ping/knock. A cheaper cure than the J&S is to simply turn the CAS to drop 2-3 degrees. However, that would not correct for A/F in the 13s.

Can you post the dyno charts from the first and second engine?

[elerner]

Were these the only incidents when your car was pinging? Or had you experienced pinging before? While I'm interested in not blowing up an engine, I also would rather put $$ in the right place, like maybe with an AFR setup with some type of warning capability (Zeitronix)

[Race Grandpa]

To the best of my knowledge my ears did not hear any pinging at any other time.

The insurance premium is a small price to pay. Think of the possible alternative. :nono:


Were these the only incidents when your car was pinging? Or had you experienced pinging before? While I'm interested in not blowing up an engine, I also would rather put $$ in the right place, like maybe with an AFR setup with some type of warning capability (Zeitronix)

[Race Grandpa]

The detnotation could have been caused by inadequate fuel pump.
:confused:


:hang:

[mx3jmcb]

I simply think 94-97's need higher pressure hence an ajustable pressure regulator....i'll be able to confirm that soon enough as i said in my other post.

The bigger fuel rail and the lower fuel pressure from the 94-97's might not be the best combination.

Until then, ill back off a tad after reading this post.

[Serpico]

Good move getting the J&S. I got mine last year and have had no troubles with detonation since. Before I installed it I had problems with pinging no matter how rich I ran. Well, I did manage to stop the pinging by running around 10:1, but I also lost 20hp (proven on the dyno).

It's a great piece of equipment and does its job very well. Having the knock gauge is also a big help in dialing in the amount of boost retard needed.

Right now I'm pulling about 1 degree of timing per pound of boost starting at 3-4psi and see no activity on the knock gauge. If I throw in a couple gallons of 100 octane , I can reduce the amount of boost retard a little and still see no activity on the knock gauge.

IMHO, it's better to stop pinging before it happens rather than letting a knock event happen and waiting for the OEM ECU to pull timing (for those of us with 99' and later years with the factory knock sensor).