come on i dont push the car hard i just drive it like i own it. i am really hoping to run 11.8's with the new motor but i doubt it will happen. i am going to try the ssp trans fluid see if i get any better track results with that.

new parts wil include. arp head and main studs, acl bearings, wiseco pistons, eagle rods, BC valve springs and ssp fluid, maybe i will put down 350awhp now but we will see. bringing the rev limit up to 8500rpm will help my track time to because i might be able to run out 4th gear now instead of shifting to 5th in the 1/4 mile

 

[QUOTE]Unless the problem can be duplicated in a controlled and well-monitored environment, it's still a guessing game at this point. And who in their right mind would want to try to have this happen again./QUOTE]

Ahem*** my husband....which is why I said the 4b11 are junk. It was sarcasm. I know that I have one, and I love my car. But would i risk who hotshot, and andy5 have done? No i wont lol But to each their own.
Engines have their limits, even tho some do not like to admit to it. AHEM andy5 :P

 

We ran a stock ralliart long block for the entire race season last year in our EVO X. The motor put down 500whp+ all season long, running 27-32lbs of boost.

After reading this entire thread, the quotation above is exactly right. We have built many 4B11 engines. We have personally seen this same issue with several stock engines. The 4B11 is a good solid platfrom to work from.

 

ya these motors definatly seem to be hit or miss. i guess i got a miss but i did run my car hard for 50k.

 

^ Yup, my guess as well. I caught mine relatively early while on the dyno. The sound of the motor changed imediatly after bumping the rev limiter at the top of a pull so I shut it down and did a compression check.... The chunk of piston hit the plug and bent the electrode. All i can base the opinon on is how mine failed and the basic design of the enigne.... assuming the engine can spin over freely there is no way the piston will touch the plug unless something else has gone "wrong" first.

There has been a lot of speculation about cyl #4 running the leanest of all 4 since it is at the end of the log but I don't buy that theory at all, the injector is pointing at the back face of the valve.... unless of course it's a fuel rail issue. I ran an egt probe on #4 on mine... never ever saw over 1550 F not even on the final pull.

However, i have yet to see anyone mention that one of the valve cover vents dumps into the manifold directly above #4 cyl... so #4 may be prone to ingesting an oily air mix... and as a result be more prone to detonation. This could fail a plug over time or the piston or rings.... any of which could introduce debris into the cyl and cause all sorts of damage.

Detonation and pre ignition (not the same thing btw) both break down the boundary layer which in and of itself will cause melt damage. I'm not an eninge builder though so take what i say with a grain of internetz salt

 

you know i have a question and it might be a stupid one but whatever. why was the piston and cylinder completely dry only on the one that blew but all the other cylinders still had oil in them? i am new to the whole motor blowing up ha ha.

 

I know it's a pain, but can you wipe the piston tops dry and re take the pics. Hard to tell if there is det pitting, chunk pitting, or just light reflecting off the droplets.

 

Proly from the fireball that rolled through the cylinder at each bag cycle

 

yes sir i can do that i will post them up later since they are in my buddies garage my garage is just not big enough for my car and to take apart the motor.

 

oh ok thanks for the info. i can also get the dyno logs if your interested in the info.

 

Think running 9's instead of 8's would've made a difference?

I've always understood you need a range colder for every 100-125 whp you add over stock. IDK what numbers he was putting down prior to this but could he have been high enough for a colder plug?

Worse that could've happened would've been a fouled spark plug rather than a blown up engine.

 

I don't think the heat range of the plug effected the piston. I believe he is at 330whp 29xwtq. Many people have taken the stock evo x plug well beyond that. If I can recall I be leave people where having some problems breaking up in the upper RPMs with the HKS plugs with a colder range.

I'd almost say it had a lot to do with when that metal piece stuck in the turbo cause a lot of back pressure in that cylinder and most likely heated it up. Or the injector started wasn't spraying enough fuel. Theres just a lot of things that could of happened. Could of just been the abuse he has put on the motor from driving it, and hotshot you can't tell me you don't abuse your car lol.

 

come on andy5notarobot we never abuse our cars we just drive them the way they were intended to be driven.

 

Sorry. Harder than most people.

 

here are pictures of the pistons cleaned and one of the blown pistion