There's ALWAYS video Too much he said/she said, we like to have gopros on every car and a scout car.

I'm not aware of any deck thickness differences, but I could check. I went through both head gaskets last year on a 55k motor so I certainly wouldn't say it's a 55 only weakness.

 

If you're lifting your heads, you're most likely detonating. Did you push coolant? Where was the gasket blown?

 

Thanks for posting, really enjoying watching this.
Seems the heads lifting may be more than just bolt choice?
Like I'm telling you something you don't already know...lol.

Good luck!!!!

 

Great minds think alike... Was just talking to him about that earlier today

 

Exactly. Lifting a head is an engine design being asked to do much more than even its design limits would provide. Meaning detonation.

Detonation is an engine trying to make, on an individual cylinder basis, 10 times more than normal. So a 50hp cylinder detonating is now trying to make 500hp worth of pressure, and the piston and head are not designed for this.

A 100% free of detonation motor is perfectly safe at very high power levels for lengthy periods. Its the detonation events (and pre-ignition) that end things.

 

Obviously you have a tune on the motor, do you feel the compression ratio is such that it is causing the detonation issue or are you getting ahead of yourself. You know how the engine was performing until this event, were there any other obvious signs, noises prior to this failure.
Personally would check the torque on the other head to see just what the value is as I stated before ARP bolts have (at least in my case) seem to need additional torque checks to assure proper values. And yes head and deck surface needs to be aggressive enough to hold the gasket in place. I am still thinking the fasteners have loosened, hopefully I am wrong.

 

I haven't torn the motor down yet so I don't know where it failed. I pushed coolant internally into the oil/chamber(s) and externally on the driver side.

My first instinct was to blame the components, I assumed the ARPs either loosened or were not up to the challenge, and a tougher stud would do the trick. After some thought, this is probably not the case and the root cause is elsewhere. I'm not saying I won't upgrade to more serious ARPs, just that if that's the only thing I did then it would be a bandaid.

Unfortunately I wasn't datalogging when it happened but I'm now looking a lot more closely into the data I do have to track down the true root cause.

Like I already stated, I'll be pulling both heads and measuring stud stretch. The engine purred like a kitten and made power everywhere, not a peep or sign of weakness. I'm 100% confident the only thing the added compression did was make more power



Rest assured guys I'll get the motor out soon, it's just been a little too hot lately and I don't need it on the road with all my other crap, lol. I'll keep this going and report my findings when I have them. At this point, everything is just speculation.

 

The added compression would require less timing in certain cases as with 10:1 and the same level of boost, the package will become fuel-limited (meaning detonation on anything below, say, 93 octane or 98 octane).

We wish you luck. I know I do. I am putting together a purposefully high compression motor in a different car AND adding boost. And running e85.

 

I actually requested a tune with lower timing when I put the high comp motor together. Fortunately, I'm not really fuel limited (in this specific reference anyway) since I'm also on E85.

 

I'm just going to set this right here.

 

Just a small amount of combustion pressure in the coolant system! You are fortunate that it did not rupture at those speeds. It could have gotten ugly in the blink of an eye.

I am quite impressed with the build process. I would get the beast tuned in person next go around though. Find out what makes it happy, and healthy.

 

Damn bro!

 

Yes indeed...coolant on the tarmac is like ice. In warmer climates, I'd run straight distilled water. In fact, I do on the track. (with some No-Rosion added).

Some years ago, was at Watkins Glen and had a garage-mate with an FD (3rd gen RX7) Explained to the driver how the plastic overflow tank is problematic (they split) and should have it replaced right away. (had a number of RX7's and knew them very well) She dismissed me with attitude....next session out, it split, dumped coolant and she hit the armco, providing a quite large blue strip and dent down the car. Of course, didn't have to say, "I told you so."

That reminds me: anyone make a larger/thicker radiator for these beasts?

 

Actually, when I lifted both heads last year I blew the end tank off at high speed, lol. Windshield was covered but the car was stable, just like this time.

I have access to a dyno, this was the first day out.. a shakedown if you will. In person really isn't necessary, data is data. I'll be making a lot of adjustments to my tune before really leaning on it this time around

Yep, plastic tanks are bad. From my research last year, I could not find any better radiators and considered running a customer all-alum piece but preferred the OEM fitment because I didn't think I'd be blowing it up again. Hindsight is always 20/20

 

THIS run was on 100% e85? And you went less on timing? And you blew the head up?

What are your plugs? e85 doesn't like hot spots. It will pre-ignite. Plugs need to be like a pecker in the south pole - very very recessed.

 

It's October then.. Read it all. You kinda went crazy with a different motor. I liked how you did it, but crazy. You were guessing bolt stretch, but maybe the threads in the block let go? Isn't this an E63 issue? Update? Hungry for more.

 

Well, If I wasn't REALLY hungry for more info, I am now..

True MBW fashion eh?

 

Yep. Bunch of info and pics, then boom, nothing.

 

What info are you looking for?

The threads in the block were perfect, all studs were removed by hand. On one side, 6 out of 10 studs were stretched beyond what I would consider acceptable so the head lifted. On the other side, the top of the cylinder wall melted in between the combustion chamber and a water jacket (which was how the radiator blew up again). I purchased a CL500 short block, transferred all of my 5.4L components into the 5.0L bare block, dropped timing in the tune and she's been running fine ever since

 

Thanks. Sorry had to poke a bit - I knew you were around. Did you do this work yourself? What parts did you change to use the 5L? Which is different - stroke or bore?

What fuel was used during his this melt down? This is massive detonation and resultant hot spotting.

 

To much boost with that compression will need really good fuel octane AND a wide band to stay on top of the tune. The wide band is the only way to "see" into the engine.The general rule of thumb we go buy is for every -4- lbs of boost , add on-1- compression point. So.....10.1 compression and 8 lbs of boost is 12.1 compression. -12- lbs of boost , -13-to 1 compression and so on.My Mustang runs 25 lbs of boost on a 10.0 compression engine so I feed it as though it has 16.1 compression....C-16 fuel. Thats how you dial in the fuel numbers that you need to have.
No one wants to blow a head gasket but you have to look at it this way. I was told buy a very good engine builder years ago and still live by it that "The head gasket is the "FUSE" in the engine". You would rather blow a fuse than the whole engine. So...if a "FUSE" pops....its telling you something is off/not right in the fuel,timing/tune aspect and you can go from there.

 

I guess that answered that. So you are running a 5.0 block now. interesting. I'm guessing you are using E85 daily?

 

I used only the block and main caps off of the 5L. The crank, rods, pistons, rings, oil squirters, hardware, chains, etc were all transferred over from my 5.4L stuff. The bore is the same, the displacement difference all resides in the stroke of the crankshaft.

5L crank on the left, 5.4L (N/A) crank on the right. The 5.4L M113k crankshaft IS slightly different from an N/A crank but I didn't think twice about using this one.


The block is practically identical. Main caps 1 and 5 do not use the side bolts, they're only 4 bolt mains, so the block not machined in those areas. There are a couple other changes, but nothing crazy and these are just test blocks really. If I were spending big money on a forged motor, I would use an E55 block but with my intended purpose I'd rather keep the costs down.


I've built and pushed limits on dozens of different platforms in the last 10 years, blowing things up is kind of what I do for fun. I made this thread mostly just to show you guys what I'm doing, I'm already thinking 5 iterations ahead and not making mistakes.. but taking calculated risks.

We have a local guy here who's trapping 140s in an HX52 k24 civic who always carries Autozone headgaskets with him. He'll go out with us some nights, pop a head gasket, and replace it before he drives home that night, and turn the gasket in for the lifetime warranty the next day. It's hilarious, but very cheap insurance.

5L bare block, the car has been on E85 only for about a year and a half. Recently, I've decided I want to start road tripping in the car again so I may be cleaning up the E85 tune and changing gears to refine a 93 tune for long distance driving.

 

Can you map switch or would load up the petrol tune when you had too? You are in Michigan, so you are surrounded with e85 stations.

I mapped a trip and I can get to ohio if I plan well enough for stops and have a tank in the vehicle of some sort with e85.

 

I flash straight to the OBD, takes 90 seconds. I would just bring the laptop and cable with me, it's in the car most of the time anyway. E85 is EVERYWHERE where I live, but last year I drove to Maryland and had to put 93 in the car twice to get to the next E85 station. I also had two 5gal cans in the trunk. This is just too much trouble, I'd rather be able to switch and be down a little power on road trips