Got a new oil pan welded up, slapped it on the ol' civic and went out a tuning. Everything great up to 24lb but we're blowing spark out above.. it is to be expected, the plugs are old.

OK OK, we're making plenty of power right now so we decide to call it a night and swap out to new plugs tomorrow. That was Saturday night. The plan was to have the car at the end of our fuel system again by Sunday, and head to the dyno on Monday to throw some numbers down.

Sunday morning, I get a call. "Come on over, pick me up, and we'll be off," I say. 30 minutes pass, I get a call he's at the e85 station, and he'll be here soon. Excellent, I think.

I get another call, "I blew the motor." What what what?!?!

lol, I didn't believe it.
















Blew a triangle about 2" wide by 3" deep out of the top of cylinder 3. It's [freak]ing savage, and I have no idea what could have caused it.

The car wasn't detonating according to cans the night before, and he even did a few pulls w/ the cans on in the morning. No detonation.

It was a [freak]load hotter Sunday afternoon, and the rings were gapped rather small, I cant recall but I think it was in the order of .0029. What the [freak] caused a chunk to disappear out of the sleeve?

Low cam timing flattened out around 4k at 22* for 20lb.
High cam was mostly a flat line at about 27* for 20lb.
LS block/crank revving to 8k.


PS: The coolant is all lovely and rusty. That's the beauty of telling your friend to add anti-rust agents to his water for 6 months.


w00t, kind of. Not at all. :/


Modified by Si Shane at 9:08 PM 4/14/2008


Modified by Si Shane at 9:10 PM 4/14/2008

 

I think the "hotter on sunday" part may have done it. Obviously it detonated

Sleeves nxt time i'm guessing

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Si Shane &raquo;</TD></TR><TR><TD CLASS="quote">

Blew a triangle about 2" wide by 3" deep out of the top of cylinder 3. It's [freak]ing savage, and I have no idea what could have caused it.

The car wasn't detonating according to cans the night before, and he even did a few pulls w/ the cans on in the morning. No detonation.

It was a [freak]load hotter Sunday afternoon, and the rings were gapped rather small, I cant recall but I think it was in the order of .0029. What the [freak] caused a chunk to disappear out of the sleeve?

Low cam timing flattened out around 4k at 22* for 20lb.
High cam was mostly a flat line at about 27* for 20lb.
LS block/crank revving to 8k.


PS: The coolant is all lovely and rusty. That's the beauty of telling your friend to add anti-rust agents to his water for 6 months.


w00t, kind of. Not at all. :/


Modified by Si Shane at 9:08 PM 4/14/2008


Modified by Si Shane at 9:10 PM 4/14/2008</TD></TR></TABLE>

any time your playing with higher boost and/or higher power on stock sleeves your rolling the dice. some work great, others dont....some last a really long time, others--not so much

 

omg, 27* at 20psi ? lmao

i guess that det can doesnt work well.

 

It was a lot of timing, but it wasn't detonating. That was clear.

We were 3* retarded compared to values that lightly detonated.

 

so you mean to tell me that 27* with 20psi had no detonation, while stock timing map only uses ~28* w/o any boost ?? i jst wanna make that clear first.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zex_cool &raquo;</TD></TR><TR><TD CLASS="quote">so you mean to tell me that 27* with 20psi had no detonation, while stock timing map only uses ~28* w/o any boost ?? i jst wanna make that clear first. </TD></TR></TABLE>

I agree.. That is a lot of timing. Maybe the dizzy wasn't synched?

 

what are you "tuning" with ?

 

E85 ethanol!? 110 octane maybe

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zex_cool &raquo;</TD></TR><TR><TD CLASS="quote">what are you "tuning" with ?</TD></TR></TABLE>

We were "tuning" with Crome.

 

just wondering, have you tuned other motors running that kind of ignition at 20 psi?

i understand that e85 slows down the burn but damn you were cutting it close. Anyone know approximately how many more crank degrees it gives you until you reach peak cylinder pressure?

 

I gave the car as much timing it wanted while it wasn't detonating, then backed off 3 degrees. I'll take the dizzy wasn't synced before I believe that I was spinning 205 KDW's in 4th gear with peak cylinder pressures at TDC.

What do you think? I don't know how e85 affects combustion with regard to crank angle. It's also scary to think about the combustion chamber design in that picture compared to the nice Honda one.


Modified by Si Shane at 12:42 AM 4/15/2008

 

peak cylinder pressure at TDC = boom

the pressure has no where to go but "out".

what do the other plugs look like?

 

The other 3 look normal.

 

why tune a stock motor so aggresively?

how did you know what timing the motor wanted without a dyno?

 

what kind of DET can were you using?

 

cant see the pics

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">what kind of DET can were you using?</TD></TR></TABLE> its in the pic, that yellow hose thats connected tot the block near cylinder#1.

motor wasnt stock, right ?


what kind of plugs were you using ??

 

Peak cyl pressure should be a few degrees after TDC, I can't recall the exact #. If you knew much about MBT, you are supposed to tune to the least amount of timing to get the most power. Meaning a motor may make 98% of its max torque with 18* of timing, while at 24* it will make 100% - but slight amounts of knocking (or misfire due to pressure & plug gap) will bring average torque down, if not destroy the motor.

The whole reason you tune a basemap conservatively, as well as while street tuning, is that you can't really find MBT. There's also phantom detonation, which is like a bad fart - silent but deadly (serious) The 10-20% you may lose from the conservative tune is usually considered a decent tradeoff for $150-500 that may be spent on a dyno tune.

BTW if you are tuning with a det can, you should also be tuning with the plugs. You should at minimum check them for the timing lines on the straps at peak torque and near redline. It takes time, but its very accurate. It can also show phantom detonation.

 

We were planning on swapping out to new plugs. We did the first shakedown tunes at night, and pulled everything in to finish up in the day time.

The motor has been built with this turbo on for the past 2 years.

I am aware of MBT, and TBH I think 3* backed off of detonation is a fair amount.

 

the pics are not working...
I WANT TO SEE TO

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike@synapse motorsport &raquo;</TD></TR><TR><TD CLASS="quote">why tune a stock motor so aggresively?

how did you know what timing the motor wanted without a dyno?</TD></TR></TABLE>

It would sputter around 20-23*, and really came into it's sweet spot above 27*, and no detonation till up around 30+. Why run any less, we were definitely below MBT.

Does stock motor mean stock sleeves? There are the endyn modified wiseco pistons and some eagles in there.

 

So who else is running 27*+ on their stock motor...or even built motor on 20psi+?

 

A built (sleeved) motor on race fuel can take a good amount of timing, but I'm not sure I would have tried that much ignition advance on pump gas, nor even started tuning at all without first synching the distributor anyway.

But I dont do WOT stuff on the street first, I use the dyno..

 

The distributer was synced the last time it was removed/reinstalled (3 months ago).

We run E85.