1G Broken Arias 10.5:1 pistons help.

[HaulinTSI]

I recently bought a 1g talon fully built with less then 200miles on it. Compression was 125 across the board. Had no tune and a 1g nt ecu in it. Well long story short i went wot by road rage and started to misfire . I did another compression check and found 60psi in cyl 2. I pulled head off to see a piston hole. All other pistons look horrible and pitted and a crack in one. My question is can i call arias and match pistons and throw them on and put motor back together? Walls look good. Pics attached.

 

[A Sharp]

I dunno about those cylinder walls. That one in the picture looks pretty scored up to me. Rule of thumb: if you can feel the scoring with your fingernail, you should do something about it (ie bore/hone).

Is this a turbo car? If you were running a nt ecu in a turbo car, I feel like the timing would be way too aggressive. Those pistons just scream preignition.

 

[HaulinTSI]

Yes 91 awd turbo. Also nails dont catch anything its smooth all cylinders

 

[91talonts1]

Going by the amount of metal missing from and sticking to the pistons, I doubt the bores are okay. The entire engine needs a thorough cleaning.

Must've been one hell of a pull if only took one to do that.

 

[94awdcoupe]

thats the worst detonation damage ever. thats not from one pull. would take 100s to get that bad.
normally I would say no way in heck the cylinders would be good. but pistons and rings look perfect below top ring. looks like cylinders will actually be usable.

 

[HaulinTSI]

I was in 2nd gear and hit wot, usually it would cut out around 10psi on 30% throttle but this one time it just suprised me and had a ton of balls. Then it started to misfire after i eased into 3rd gear. Spark plug in cyl1 electrode was burnt off. I pulled all pistons and rods. The cylinders honestly are all smooth.

Like i said this engine was just all done from top to bottom. All Bearings, arp studs, gates timing belt,water pump, tensioner, new crank, manley i beam rods, kiggly springs, hks 272 cams etc.

I'm curious to find out why the pistons look like that? Is it from the NT ecu? Because the engine literally has 200 miles on it

 

[bastarddsm]

Is this turbocharged? We'll need to know your whole setup, but yes it is likely that it is from running an n/t ecu.

 

[HaulinTSI]

I posted engine build 10.:5:1 arias with manley i beam rods. Arp studs. Mls head gasket. Hks 272, kiggley springs, 3g lifters, new bearings, 16g , 2g maf, new crank etc

 

[HaulinTSI]

It also apparently has 660cc injectors i cant verify because injectors have nothing on them. Heres the pics of nt ecu and injectors

 

[bastarddsm]

How would you ever expect this to run right?

 

[HaulinTSI]

Sorry, I bought it like this. I was told it had a 2g black box ecu. It idled messed up and they guy kept playing with biss screw.. I think he was confused.

I'm thinking the shop that built the motor lied to him about the ecu. Since I bought the car it never idled right which makes sense with no tune and a NT ecu with 2g MAF. Is that why the pistons got so f***ed up?

These are the worst pistons I've ever seen on any of my motors and it only has 200miles on it. Could these pistons be that bad because of ecu tune? Within a couple hundred miles if that?

My question is since everything was balanced and new would it be safe to throw 4 new pistons on and put it together? Of course get a turbo ecu. But looking at the walls bearings and crank and head everything looks great. Should i match the weight of the pistons going back in since the block was balanced already? Or should i be ok with throwing new pistons on.?

By the way does anyone know how to read the numbers on Arias pistons? I'm assuming 8602 means 86mm .020over?

 

[SasaniFab]

You have been doing wot throttle pulls on this motor? I would have your block bored out to .004 over , keeping it that way is half ass in my estimation. Those pistons are ROcked! The block should be cleaned thoroughly at the minimum to make sure your oil passages are spotless.

In my opinion any engine that had any form of damage ie. spun bearing, broken piston etc should be checked over By a machinist or competent mechanic.

 

[HaulinTSI]

I have done 1 pull by accident in 2nd gear. But theres no way in hell my one wot caused this. These pistons must of been burning up at idle or something. Or the owner before me beat on it with a fresh motor. I think im going to hone the cylinders and throw the pistons and rods back on. The block looks very clean. And i dont have the time or money to be yanking the block out and stripping it down. When it was just all done.