miata2fast

iTrader: (2)

You have a detonation problem on all 4 cylinders clearly. Those clean spots on the piston edges and ridges are not good. I would rule out the coolant reroute, and concentrate on tuning issues. I think you have the timing way to hot.

When you pull the pistons, report on how much tension you have in the rings. Over heating would make them weak, and you will notice cylinder wall scuffing and piston scuffing. Detonation will not necessarily have an affect on ring tension. Over heating will.

johnmatt

iTrader: (8)

Got ya beat

Braineack

iTrader: (62)

gospeed81

iTrader: (51)

You pussies don't even know what det is...

levnubhin

iTrader: (30)

You ******* need to learn how to tune lol.

<- hopes to never eat those words.
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

wayne_curr

iTrader: (8)

This should all be making Mr. Ganger feel better about his engine.

hustler

iTrader: (6)

lol @ pushing it and not finding the conservative happy place.

90R

iTrader: (4)

why do #1 & #2 rods have rust on them?

is the head flat?

gospeed81

iTrader: (51)

My tune was conservative, for me. Water injection, Brainy's advance dialed back a few degrees...

You know who killed mine, you met him. Let him borrow it over Christmas break and he brought it back smoking.


New tune will be higher resolution MS2, crank trigger, and real, new injectors. Water injection soon to come, just missed a good deal from Sav, but eyeing splittime's setup.




Dopple, I'm in to see where your tuning went wrong as well. I thought my timing advance table was gravy, but you can see from the above there were some bad spots in it that ate up the motor during consecutive pulls (although he said he was eating up STis and such and having fun, so oh well).

Doppelgänger

iTrader: (12)

Well, it was tuned by a VERY respectable tuner here in GA. The guys tunes TONS of stuff...everything from carb'ed turbo cars, to SPEED challenge cars, to Spec Miatas, to high-strung all motor Hondas. I trust him. Actually, I was running that tune since a month after I bought the car. Tracked it, drove it across the country, daily'ed it...everything. Something happened pretty quickly..as in within a couple of weeks before the failure. I'm almost wondering about a bad tank of gas that I got the week before at some podunk station in Alabama.

Cylinder walls are perfect and the cross-hatching is visible as it should be. No scoring, gouging or scratches at all.

AutoFreak57

iTrader: (3)

How many miles did you have on that setup again? I think it was a lot if I remember right

Doppelgänger

iTrader: (12)

FWIW, I wiped the carbon off the pistons tonight and found some small pitting on #1 and #2 by the exhaust valve area but not much on #3 or #4.

Edit- fuckit here are pics of the pistons with a little rubbing off...

piston #1



#2 on right #3 on left



#2 close



cross-hatching



#4

lordrigamus

iTrader: (14)

What about air temps? I've seen the hottest AITs ever in my car during this never ending heat wave. Yesterday was the nicest day we've had in two months up here.

I agree with the above mentioned thoughts as well. 1&2 look bad and the#1 rod does look bent. Don't be surprised if the ring lands fall off of #1 when you pull it. Post that spark map anyway, inquiring minds want to know.

sixshooter

iTrader: (12)

So Doppelganger, do you think the reroute with the 01+ headgasket was the primary problem or do you think your tune needed less spark advance when IATs get above a certain threshold as was proposed by Lordrigamus?

Doppelgänger

iTrader: (12)

I think it was the reroute. Seems the lack of flow around the topend on 1 & 2 indeed caused excessive heat/detonation. I will be adding a front t-stat and plumbing to my reroute very shortly.

miata2fast

iTrader: (2)

I have my doubts about the reroute. All four pistons look like they have been in a tumbler. That is not a overheating issue That is many miles of fun.

Let's face it, a boosted engine that is beat on is not going to come out unscathed with stock pistons forever. Even with a conservative map.

Doppelgänger

iTrader: (12)

I don't have a map on my work computer, but I do have a 1st-4th gear pull .csv log where you can see what my timing was doing under boost

Doppelgänger

iTrader: (12)

True, but there is obviously more issues with 1&2 where it's known that the design of the 01+ HG reduces coolant flow significantly.

fooger03

iTrader: (2)

Just out of curiosity, you weren't the one that posted a recent vid of your car hitting 26 psi, were you?

Doppelgänger

iTrader: (12)

nope, not me.