ATTENTION NEW OWNERS: STARTER INFORMATION-How to prevent blowing up your car.

MONK13

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This is the MOST useful thread I have come across, I will be bookmarking it so I can come back to read more to make sure I'm not currently, past, and future screwing up my precious Si which is the most fun thing I am doing (with my clothes on). My appreciation to the OP! Excellent work.

Side note: even without common sense, if you read the OP post and not prevent or fix something your doing that can harm your car, then its not missing common sense, its an abundance of STUPIDITY. And like they say-- "YOU CAN'T FIX STUPID"

<exiting soapbox>

<returning to your regularly scheduled program>
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schrisi

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This is the MOST useful thread I have come across, I will be bookmarking it so I can come back to read more to make sure I'm not currently, past, and future screwing up my precious Si which is the most fun thing I am doing (with my clothes on). My appreciation to the OP! Excellent work.

Side note: even without common sense, if you read the OP post and not prevent or fix something your doing that can harm your car, then its not missing common sense, its an abundance of STUPIDITY. And like they say-- "YOU CAN'T FIX STUPID"

<exiting soapbox>

<returning to your regularly scheduled program>
Yeah, my post about common sense was just a joke. In another thread about a blown engine, I said it'd be nice to have a post like this. OP posted just about exactly what I posted here, but thankfully he went ahead and made this post anyway!
 

jason510

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Completely avoid heavy throttle scenarios or 3k+ rpm as much as you safely can until the car has been operated at least 15 minutes. Keep in mind all the metal in the engine and transmission expands and contracts when hot and cold. Bearing tolerances, piston to cylinder wall tolerances, etc are much smaller when cold and expand to the intended design tolerances once up to temperature.
I have a question about this...so those of us that have a commute shorter than 15 minutes cannot drive past 3k+ RPM's? Anyone else have any input on this? I certainly don't drive my car aggressively 95% of the time, but often drive shorter commutes. If this were the case, then why would I buy a Si?
 

fenix-silver

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Checked some logs for the first time, inspired by this thread.

STFT spiked to ~18 at times, but LTFT was a pretty constant -3.13.

AFR of about 13 at WOT, 15 idling. It rose to 29.4 several times, but TPS was 0. I think I was either braking or completely stopped at the time. Nothing wrong with that high value there, right?

IAT a constant 140 degrees.

All seems fine to me, but I uploaded the log I'm looking at. Would really appreciate if someone could double check. The only mod I've done is TSP's stage 1 tune. Thanks!
I didn't look at your log, but I hope you aren't seeing an AFR of 13 at WOT. Should be around 11.0. 14.7 is stoich, so you should see that when cruising off boost, idle, etc. When you let off the throttle while cruising or coming to a stop, the ECU (likely) shuts off the injectors, which is why you see the 29 (basically full lean as there's little to no fuel).
 


schrisi

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I didn't look at your log, but I hope you aren't seeing an AFR of 13 at WOT. Should be around 11.0. 14.7 is stoich, so you should see that when cruising off boost, idle, etc. When you let off the throttle while cruising or coming to a stop, the ECU (likely) shuts off the injectors, which is why you see the 29 (basically full lean as there's little to no fuel).
I saw AFR go as low as 10.8 or so in one set of logs I did, but I'm not sure if that corresponded to WOT. I assumed WOT would be indicated by a high TPS value. When AFR was 10.8, TPS wasn't that high.
 

hicompb18c1

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As a comment, the TSP Stage 1 tune calls out 91-93 octane as a requirement on their product page, and no longer a recommendation for that tune.
Have you come across anything else about how the TSP is affected by octane? I've found a noticeable difference between 91 and 93 gas in the past, even in NA motors, so when they say 91-93 is now "required" my first thought is whether or not 91 will actually be OK or not...
 

charleswrivers

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Have you come across anything else about how the TSP is affected by octane? I've found a noticeable difference between 91 and 93 gas in the past, even in NA motors, so when they say 91-93 is now "required" my first thought is whether or not 91 will actually be OK or not...
The dynos provided are, from memory, based on 93... so expect less power possibly under sustained hard driving and K.cont will rise earlier... retarding timing and lowering power to prevent knock.

As we say in the Navy though... the low spec is still in spec. Since 91-93 is given as required from the company that is reselling what @D-RobIMW made... I'd say 91 is good enough to be safe, albeit with a trade-off in a k.cont that's going to move sooner/more.
 

fenix-silver

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I saw AFR go as low as 10.8 or so in one set of logs I did, but I'm not sure if that corresponded to WOT. I assumed WOT would be indicated by a high TPS value. When AFR was 10.8, TPS wasn't that high.
Yes, WOT would be high TPS. I was kind of using WOT generally to mean high load. The best way to check things is to compare your AFR vs target AFR.
 
OP
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"Afr" is the raw o2 sensor reading which as it heats up (say during a pull) will tend to read richer (lower numerical value) than the true afr the cylinders are seeing. Both hondata as well as k tuner have a "Afr corrected" value which is closer to the true afr the cylinders are seeing as they have compensated for the skewed raw afr reading when in boost.

The best thing to watch is all 3

Afr
Afr. Corr
Afr target

Target is what we tell the engine to hit
Afr is raw sensor reading
Afr corrected is what presumably is the "actual" afr the cylinders see.

Afr does tend to run around 10.51 to 10.8 while the corrected value should be closer to target ( in this example 11.20)
 


Cry16

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I got a CVT Turbo with Ktuner. I’ve been using the 21 PSI map since i wasn’t able to load 3 different maps into my ecu for whatever reason. But now i’m worried about blowing my engine since i drive like a mad man most of the time. Thinking about selling the ktuner since i feel like i’m not responsible with it. I don’t check logs nor do i check temp or all that. Don’t want to mess up my precious car. Also run on 93 octane only. Should i sell it? any advice. Heard that most people that blow their engines have a tune on.
 
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This was never intended to be a scare tactic post to freak anyone out. I think you would be fine but nobody can predict the future. Maybe try not driving like a mad man? Or implement some of the advise given in the original post? Both?
 

gtman

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I got a CVT Turbo with Ktuner. I’ve been using the 21 PSI map since i wasn’t able to load 3 different maps into my ecu for whatever reason. But now i’m worried about blowing my engine since i drive like a mad man most of the time. Thinking about selling the ktuner since i feel like i’m not responsible with it. I don’t check logs nor do i check temp or all that. Don’t want to mess up my precious car. Also run on 93 octane only. Should i sell it? any advice. Heard that most people that blow their engines have a tune on.
As long as driving like a mad man doesn't involve constantly brake launching your car and you haven't disabled boost target target dampening you should be fine.

Also, consider running a full datalog including some WOT pulls and some "non-mad man" type driving. You can even upload the log here as a .zip file and someone will check it out.
 

Andre

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Can anyone look at my post and give me some help on diagnosing my problem?
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