LinuxRacr's Haltech E6X Log..
- Thread starter LinuxRacr
- Start date
according to Beau at MAM, it's a valve. I got him on the phone and put it near the engine. He said if it was rod knock it would be affected by pulling the injectors one at a time and seeing what happens. That combined with not matching RPMs says its a valve. Fun, eh? I must have let something get in there, but I have no idea how.
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- 2001 Mazda MP3
exactly 
TurfBurn said:
With crappy 91 octane gas, I was told to tune less then 12.0. The Dyno guy I use here tunes a lot of high HP mustangs and such and he said that with crappy gas and high heat, you want to be less then 12.0. (12.0 1ould be the high mark) I noticed on the dyno that as I got hot, I had to richen things up to prevent the J&S going off. Linux is in a high heat area and I think they have 91 over there too, so 11.7 should be good for his climate. I run much better and consistant in the 11.8 area with AZ pump gas and heat, no J&S activity with the same amount of timing out as before when running 12.0-12.2 when I was in MD. I didn't know a couple of tenths would make that difference, but it does.
Bigg Tim said:
11's are safe and happy.. just not as much power available... it's a real tradeoff between the power aspects and trying to stay safe. Our cars should peak in output at ratios around 12.2-12.6 AFR... which is pretty lean for the amounts of boost.. the trick is mitigating that versus your timing, obviously you have to retard timing to go that much more lean, but you obviously don't want to lean it out all the way if you have to pull so much timing that you lose the benefit of the AFR change... basically there should be an optimal point where you can run a maximum amount of timing and go as lean as possible to peak out your overall output... I believe that it is right around 12.0-12.2 that this occurs, but I don't have proof as of right now. From some of the lab work I did a while back, we found much better power increases from AFR than we did from timing, so I lean toward using the AFR over the timing a bit now... but I'll double check and try and post up the rough percentages we saw in our testing between timing and AFR and the power yields when things were held fixed.
But you don't want to pull down into the mid to low 10's as you start getting into those other danger zones of pre-ignition and cylinder wash as I was discussing before... 10's are pretty safe overall, but in the long run it can become an issue.. if you get under 10 then you will very soon have oil that smell strongly of gasoline... as long as your oil isn't picking up any hint of the scent of gasoline you should be dry enough that lubrication on the walls is staying ok.
And... we run 93 octane up here... so
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- 2001 Mazda MP3
timm, did keith tell you that? (was he the dyno guy you are tlaking about)
hahah yeah sucks in AZ crappy ole 91 octane!! TGF michigan! 93
hahah yeah sucks in AZ crappy ole 91 octane!! TGF michigan! 93
YUP, keith told me that when I was leaning out the A/F and adding timing. He said for a dyno run with high octane gas 12.0 to 12.5 may be okay, but with pump gas, stay at 11.5 to 11.9 to prevent detonation. In the summer it's worse because of the intense heat.
I had 14 or 15 degree's of timing out and 12.2 and only got 4hp. Any more timing and the curve started to get choppy. After 2 runs at 12.2 or so, and 14-15 degree's out, the J&S started to light up. We took the A/F down to around 11.8 or so and left the same timing and no detonation and the power was still good, may lost a hp or so, but the curve was nice and smooth.
I agree about the 10's, that's a bit too much for me, but depending on the climate and fuel, 12's are a big no no for our cars and boost.
I had 14 or 15 degree's of timing out and 12.2 and only got 4hp. Any more timing and the curve started to get choppy. After 2 runs at 12.2 or so, and 14-15 degree's out, the J&S started to light up. We took the A/F down to around 11.8 or so and left the same timing and no detonation and the power was still good, may lost a hp or so, but the curve was nice and smooth.
I agree about the 10's, that's a bit too much for me, but depending on the climate and fuel, 12's are a big no no for our cars and boost.
I just checked the old lab report again... In the 11.5-12.2 range you roughly gained .38% in output per .1 change in AFR toward the lean side. However in the 10-11.5 range you get considerably greater gains by leaning out the car. Running at stoichemetric fuel ratios, advancing the timing resulted in about .43% gain per degree of timing you can add. So obviously timing and AFR are pretty close to one another. Advancing the timing can be beneficial as it does result in cooler exhaust temps which can prolong valve and turbo life. So from those standpoints running a little richer and pushing the timing a little more is beneficial. However, the timing accuracy in our cars is not that fantastic, so there is "fudge" room in any timing value, and additionally, AFR isn't that easy to control and smooth out down to a tenth or two. So it's a tossup. But obviously your gas affects it a good deal as well!
Later,
Steve
Later,
Steve
Nope... makes them hotter... detonation also makes your EGT's go down too actually... the reason for both is because the combustion occurs sooner (advanced timing) or quicker (detonation) and thus there is less burn still completing or cooling as the gases exit the cylinders and your EGT's go down... If you ever get the JandS to light up really good you'll see it happen on your EGT... the entire time you have lights on the JandS the temps start rocketing up, and as soon as they go away they start falling back down..
Werd son. After I met up with you, I went and met up with Ahmad. I followed him, and he was boosting more than me. We stopped to pick up his friend, my IAT temps approached 50 C. His were just in the mid 30's C. His temps were in the low 20's C when he was cruising at 40 MPH, while my temps were at 27 C cruising at 70 MPH. The FMIC will make a HUGE difference. Take into account that it is in the mid 60's F outside tonight. On another note, I set my max boost to 68 KPa (10 PSI), so now when I turn the boost knob to 100%, it holds at 10 PSI on my boost gauge. I have noticed more torque too since it hits 10 PSI a lot faster now. (headbang)
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