so, i broke in the motor and it was running great then took it to get dyno tuned on last friday, it was running good till this saterday and then it blew up on the freeway took it home to find thishttp://s529.photobucket.com/al...ston/ piston melted and the two middle spark plugs are fried. the machine shop said the tuner either made it too lean or too much spark. The tuner says that the af was 13:1 and the spark was not that agressive and that i probably had a bad injector. what do you guys think i havent heard of many people melting a piston with simalar set ups.

97 civic coupe
b20 block and b16 head
84mm itr pistons
arp rod bolts and head studs
itr valve springs and ctr cams
skunk 2 pro manifold
4-1 header w/2.5" collector
endyn breather system
chipped p28 tuned on chrome pro

 

your tuner really fu%ked you up.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EkFG &raquo;</TD></TR><TR><TD CLASS="quote">your tuner really fu%ked you up. </TD></TR></TABLE>

wow, gtfo! how do you know it was that without looking at a fuel/ign map, lmk guess your reading plugs

hondapowerb16a2 you mind if i ask what kind of injector clips you had??? i had a similar problem which turned out to be a faulty injector clip that fell apart...

 

Wow... those suckers saw some serious heat... I would like to hear some opinions myself

Is that a hot plug in general anyways?

 

probably was too lean...

 

Um , w/e it was tuned in, Get a screen shot of the low/high cam ign
and the low / high cam fuel.

Get a read out of the dyno, and Do NOT place the blame on anyone until other people , not just myself have seen these screens Particularly get ahold of Donf, CC, alterd, b19, 92typer or mtber

I myself can tell what happened
w/o these things i can say this
the plugs that looked to be the hottest seem to be soaked in oil or fuel
your head looks ok but same with the chambers..

Usually melting a piston is because it gets way too hot, and a sure sign of it, is at the top of the chamber on the left in one your photo pics, thats a hotttttt chamber....
more then likely with 13:1 CR i'd say it got lean, you dont melt a piston when your rich lol..at least i've never heard of it..

 

It looks to me like detonation. It's hard for me to see what the other cylinders and pistons look like from those pictures but if the piston tops look "sand blasted" and the combustion chambers look like they have metallic "sandy" looking residue in them etc, that's what it would suggest. I have seen nearly identical damage in motors that have had nitrous mishaps. Possibly a bad tank of fuel or too much timing or some combination of... Was your distributor synched properly to your tune? ie- was say 16 degrees adv = to 16 degrees that your ecu sees?

 

i was running obd2 injector clips and obd2 prelude injectors. I dont have the maps or anything, it was tuned at speed factory in tacoma they are a good shop and have alot of experience

 

send your injectors to a third party and have them tested. that should settle that claim

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hondapowerb16a2 &raquo;</TD></TR><TR><TD CLASS="quote">i was running obd2 injector clips and obd2 prelude injectors. I dont have the maps or anything, it was tuned at speed factory in tacoma they are a good shop and have alot of experience</TD></TR></TABLE>
alot of experince


so no proof the car was even tuned at all.. GJ.

 

this is the afr graph he sent me

 

Are you using a stock fuel pressure regulator?

 

blox fuel pressure regulater set by the tuner

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hondapowerb16a2 &raquo;</TD></TR><TR><TD CLASS="quote">blox fuel pressure regulater set by the tuner</TD></TR></TABLE>

my 11:8-12:1 gsr is detonating on cylinders 2-3 also.. plugs read different than 1-2.. pretty whack yo

 

I'm not familar with the blox regulator. Is it like the B&M which uses the stock diaphram? If so that can be part of the problem.

 

yes it is alot like the b&M i have a b&m fuel pressure gage too though and it has stayed at the same pressure as when it was set. how are they bad?

 

They can drop fuel pressure.

 

AFR's looked good on the graph. Looks like a fuel issue. If your car ran great for a whole day, it should have run great all the time. It would have shown it on the dyno that it was melting plugs. The plugs look like they got some bad gas. Contaminated maybe? You know that some gas stations here in WA have been getting bad fuel as of late.

Oh and EkFG..... STFU!!! SpeedFactory has been tuning for quite a few years now and most of the "Tuner" shops in Western WA call them to tune for them.

 

OK guys. Here's screenshots of his low and high cam ignition timing, and he already posted the AFR screenshot. The timing values are right in line with other similar setups I've tuned that have had no problems.

[IMG][/IMG]

[IMG][/IMG]

Nevermind the 19* at idle, that was done to help his idle. Igntion timing was synched at 16.5* in the maps, as I do on all cars.

I don't know who built the motor, but it did have rediculous amounts of blowby coming out of the catchcan setup when it was brought in, as noticed by all the guys at the shop. It ran fine, but made fairly low #'s, only 183whp/137tq on our Dynapack.

 

pre- ignition is a bitch
it prolly detonated for a while untill pre-ignition manifested its ugly side

 

jeeeeeez

 

I just ran into a guy yesterday talking about this build.. I really would like to know some answers. I kinda wanna see it

Worries me ... I am doing the same build


Is this from using cast pistons and not forged with this compression ratio?

 

So, did this thing let go while cruising at part throttle with medium load on the low cam?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by badboyr66 &raquo;</TD></TR><TR><TD CLASS="quote">Is this from using cast pistons and not forged with this compression ratio?</TD></TR></TABLE>

no.

 

they are cast rs machine 84mm itr pistons. it was on the freeway accelerating to pass so pretty close to wide open throttle at about 70mph the rpms where kinda high i was in vtec. not more than 8K though. What causes the blow by out of the catchcan? i noticed that too it would smoke out of the catchcan breather just about always. it ran smooth untill it detonated there was no pinging or any odd noises i just lost power it decelerated about 30 mph but stayed at the same rpms i looked up at the rear view mirror and noticed a cloud of smoke pulled over and it died.