Hi all. I managed to blow away ring lands on 3 out of 4 pistons in my B17A1.

Perhaps I need to due some more tuning lol.

I must have had way too much advance. My A/F were good (12-12.5:1), so that's probably the issue. Anyway, I will invest in a way to really track detonation, and tune much more conservatively so I don't have issues again.

While I'm at it though, it never hurts to add forged pistons. I'd also like to lower my CR a bit to low 9s. It seems hard to find though. either lower or pretty much stock is availabale unless I dabble in thick headgaskets. I'd prefer to keep a stock Honda headgasket....opinions on these thick guys??

I'm looking at JE 302498 (9.5CR), or possibly JE 302497 to go down to approx. 8.3 CR.

I was also looking at Arias. the 3320001 (Low comp, 8.2) or the 3310212, near stock at 9.5

Opinions?

Keep in mind there is not any E85 anywhere near here (Canada eh?). Good old 91 is the best I can get.

Thanks for any information!

Chay

 

 

That AFR is way too lean while in boost/full throttle.

As 2x0 said, lowering the CR isn't really the solution for the problem. I'd stick with at least ~10:1 pistons, and that's what I'd call the conservative side these days for pump gas FI applications.

What tuning software are you using? Hopefully either Hondata or Neptune.

 

You're right about needing a tuner, but I am going to tune this myself, come hell or broken piston lands.

Why? This is a hobby for me. Mistakes are part of the learning process, and really I set myself up to fail the first time. I will not repeat this.

Now, at the moment I was only running 7psi, but with this setup it was not enough for me. I want to end up with more power. I don't have a power goal; I have a butt dyno goal, which is kinda the same thing. anyway, I'll know when I get there.

I'm using hondata V3. I loaded, then made conservative (On the fuel side) a map from a greedy B17 I found in the vault. I should have made the spark conservative as well, but figured with more fuel I'd be ok for testing. Guess not.

I ran 12 to 12.5 all day on my last turbo GM v6 project. It remained healthy and happy. I guess Hondas need more fuel? What do you guys target above certain psi levels?

It was kinda torquless at 9.6 (Stock) lol, thus the boost! Yeah I hear you guys, it will suck even worse at lower CR off boost, just wanted to have a larger safety margain when on boost.

I guess the lower CR would hurt fuel economy too.

When would you go lower CR? With alcohol and 40psi boost??

Chay

 

Never.

If you blew it up at 7psi there was wayyy to much timing. Learn to read plugs and it'll take you far.

12.5 isnt THAT bad. I would always target 11.5-11.8 though

 

That was one thing that was interesting to me. There was a nice light brown tint on all 4, no visible signs of detonation. No spheres or anything like that.

I had run them too long to look for the spark marks for timing though. A new set will go in to see if the whole plug reading thing works, like this idea:

http://www.autorepairinstructions.com/archives/reading-a-spark-plug/

Chay

 

I guess I grew up doing Honda tuning and turbocharging without looking at plugs at each run, because we used EGT gauges and sensors in order to read whether or not there was a bit too much timing ( heat increases going to the spark plugs which was more indicative of timing changes). I'm not saying that I do not know how to read a spark plug, I do, but I have never incorporated reading spark plugs at every single run at my tuner's location. We used EGT gauges as much as possible. Is that not a consideration nowadays?

 

We rarely ever pull the plugs on our cars when tuning.

 

I never know of anyone now that has EGT probes installed, or even at their disposal for use. I wholeheartedly agree though that EGT info is incredibly valuable to have.

 

EGT on one cylinder at a time and 4 quick runs or a "just lets get sure" 10 second run and shut on a new set of plugs when the tune is finished.
Just to get sure all cylinders are same-ish.
Thats what i like.

 

True. I still use the "leanest" cylinder (characteristic of that engine) as the single point. There's no way I have enough time to see 4 sensor readings. I just kept it simple. But I do that so that all plugs are being efficient, not just for 10 seconds. (I think that's what you meant?)

 

It's old school thinking... that's more of the reason why you may not have experienced people using it... ('Cuz race-car laptop pwns all...)

 

I wrote it too complicated.
You do the tune like normal.
At the end you do 4 pases pluging the EGT sensor on each cylinder or again at the end of the tune change plugs to 4 brand new and do one heavy 4th gear pull and immediately shut the engine down to do the plug comparison when each one much look the with the others. If not you have to check each cylinder EFR again imo. Trying with heavier dyno breaks is better.
Thats all.
On the other hand you can just go with the worst(3rd) cylinder on the egt and call it a day.Its more cruitial to check each cylinder when you are on water/meth injection imo.

 

Well if your a noob doing it yourself and dont have any idea as to the general timing these cars like or where to start its not a bad idea. At least the final power pulls should be checked.

Its not something I did alot until I started really getting up in power and with E85 because its way to forgiving and you can easily overdo it.