screaminz28

iTrader: (1)

No offense, but I would think you don't have the budget to NOT do them. You just put a pile of money into the car. Are you simply doing a stock shortblock and returning it to stock? If not, you could be putting yourself back in the same boat without using better pistons. Granted, you might be fine with a stock shortblock with increased ring gap and water/meth, but it's SUCH cheap insurance to do pistons since you're doing a motor anyways, I'd strongly suggest it, as well as lowering the compression ratio. You can then turn the boost up and take better advantage of the water/meth injection.

KN_TL

iTrader: (3)

damn, that sucks. Same thing I had happen to me.

One good thing is that I ran my motor with badly cracked lands and it didn't damage the cylinder. But.....after only 35K miles, about 8K of it boosted, the cylinders were out of round which were fixed by simple honing. Unfortunately, it put it outside the clearance specs of any off the shelf forged pistons. If you're interested in some CP's, let me know.

Here is some info. These are modeled against SC70404

maddogtheta

Good to know, how many cracked lands did you have?

Luckily I am able to borrow my parent's oddyssey so I won't be putting many miles on it in it's current state.

KN_TL

iTrader: (3)

maddogtheta

Yikes. I'll be re reading your thread tonight.

KN_TL

iTrader: (3)

It just dawned on me that you're a J35....my custom pistons are worthless to you.

But it appears that the stock pistons (j32 or j35) are not tolerant at all to the combination of boost and some detonation.

maddogtheta

Oh yeah, I didn't think about that either. These pistons definitely do not seem tolerant at all.

mzilvar

iTrader: (3)

Another thing that didn't hold out if anyone recalls from tony the tiger's thread is that car originally was pushing 442HP on the stock J32 and the motor dropped a valve from the stock valve train destroying the engine. Which led to the high CR turbo build that was done to that car.

screaminz28

iTrader: (1)

Wouldn't they work with the result just being slightly higher compression ratio? Gerzand's post with the calculator and all.

CR should be right around 9.58:1

thisaznboi88

iTrader: (7)

Stock ringlands no like high boost . Sorry to see your engine blown.

KN_TL

iTrader: (3)

Yeah, got that covered in my build.

KN_TL

iTrader: (3)

Oh true, the bore is the same, just the crank and rods are different.

Does it also have the same compression height spec?

KN_TL

iTrader: (3)

Mine was only seeing 7lbs or so. I did log some minimal knock and from what I've been told, that was the likely the reason for the failure.

yungone501

iTrader: (4)

Yep, stock ringlands are very susceptible to damage even with mild detonation. That's why widening the gap of the stock rings is the best mod you can do while you're in the bottom end and plan on running boost. And adding water/meth injection is the second best. Ok, maybe tuning the damn thing correctly is above both of those but you all get my drift here I think. That's a statement that's tossed around waaaaaaay too loosely around forums IMO.

maddogtheta

I'm leaning towards going low compression forged pistons and a water/meth system at this point. I have to talk to the guys at SpeedFactory Monday about it and see what they recommend.

UTAH TSX

Don't go to low of compression that is old school thinking, you will loose a bunch of pre boost power and take a big loss in gas mileage with 9.0-1 compression, with the engine management we have and forged pistons 11.0-1 is not a problem with a proper tune, you will have to run much higher boost to get the same power and your lag will be even worse with low compression, hell the new civic's are 11.0-1 and people are running 10-12 Lbs making over 400 WHP with stock internals with a 2.4L 4cly. and they are very dependable, it's all in the tune bad tune bad problems guaranteed

maddogtheta

I didn't realize the drawbacks of lower compression. Thanks for the info. I'm going to see what the guys at Speedfactory recommend.

KN_TL

iTrader: (3)

I guess for some gas mileage would be an issue but I like the idea that low compression being less prone to detonation even with the forged hardware.

It remains to be seen if it is going adversely affect the performance but I am more concerned with margin of safety if I get a bad tank of gas or my meth bottle runs dry and I don't notice it. Also shit happens with electronic components in the hostile environment of an internal combustion engine that could cause things to go off.

Just my opinion.

screaminz28

iTrader: (1)

I agree with KN. While there are numerous examples of 11:1 tubo'd vehicles, I'd say it is the exception rather than the rule, and they have very little margin for error. Also, we can't compare to anything new OEM turbo that uses DI since that is a completely different ball of wax.

Imagine how much MORE power the civics would make with an extra 5 degrees (or more) of timing.

UTAH TSX

I'm not much on the tuning part of things. however It seems like everyone is going 10.to1 or more on street builds, with the lower intake air temps from lower boost and higher compression, detonation doesn't seem to be a problem. I was thinking that with his remote mount, automatic transmission and the lower compression, there might be a big loss in power and the turbo lag could be worse; making it a long wait for the power to hit

DomGSR-T

iTrader: (1)

Is your car TPS base or MAP base tuned?

maddogtheta

I don't know.

thisaznboi88

iTrader: (7)

2 step lower sparks would also help

maddogtheta

I have two step colder spark plugs.

DomGSR-T

iTrader: (1)

PM sent

UTAH TSX

How are things going ? have you tore down the engine yet ? we are still tuning we have about 25 datalogs with vitt changing them each time and we are still at 4 LBS tapering to 2LBS this is as low as we can go, Vitt is being being very careful

maddogtheta

I'm taking the car in to SpeedFactory Monday. They're going to pull out the cracked piston and put a new one in. They're also going to install an AEM water/methanol system.

6spd-GERCO

So now forged pistons and rods at this point?

UTAH Type-S

did they give you a quote as to how long it will take?

maddogtheta

A couple of days.

maddogtheta

Yesterday I talked to the guys at SpeedFactory and was surprised when they told me they had pulled the oil pan off to remove the piston from cylinder 6 with the broken ring lands and they found chunks of metal. Upon further inspection the piston skirt from the piston in cylinder 1 had broken somehow. They were going to look into forged pistons and get back to me.

I went in to the shop today to see the damaged pistons and talk over my options. When I got there they had a theory on why the piston in cylinder 6 had the cracked ring lands. Apparently the broken piston skirt from the piston in cylinder 1 made it's way bouncing around in the engine until they wound up in cylinder 6 where they broke the oil squirter off. This caused the piston in cylinder 6 to heat up which weakened the piston. The added heat made detonation more likely. The detonation cracked the now weakened piston's ring lands.

They had never seen or heard of a piston skirt breaking off before or how the pieces made it all the way to the opposite end of the engine and break the oil squirter off. I guess I'm just that lucky

The plan now is to replace the two pistons, replace all of the rod bearings while the pistons are out, and install a water/meth injector for added safety with the benefit of increasing timing.

I should have the TL back early next week.

VitViper

I've seen aftermarket pistons drop their skirts, it happens. Had a set at a friend's shop sitting around just to show people. Usually just bad luck. Haven't seen an OEM piston drop its skirt, seen a weird situation on a 9th gen where the skirts melted away, and only the skirts... the rest of the piston was OK.

Sorry to see you go through all this trouble, sucks to see it happen no matter the why/how/when.

UTAH Type-S

Do you know where theyre mounting the tank for the water meth?

maddogtheta

In the engine bay. I relocated my battery to the trunk so there's a ton of room up there.

KN_TL

iTrader: (3)

I suppose meth is going to help with the detonation but the stock pistons are just too fragile. Are you going to have some kind of firehouse type alarm when the bottle is empty?

If the whole thing is apart and you're going to be replacing the bottom end bearings, it just seems a waste not to at least go with a stronger set of pistons.....

EDIT:

Too lazy to look but did you mention how many miles are on this motor?

maddogtheta

I'm installing the AEM V2 water/methanol injector along with their failsafe gauge that alerts to any issues with the flow of the water/meth as well as letting me know when I'm out.

The guys at SpeedFactory seem to think that what happened to my engine was a fluke, and the information that they've been able to gather leads them to believe that the pistons will hold up. I'm inclined to believe what they tell me and trust their experience. If I have further engine issue then I'll know for sure that I need to go with at least forged pistons... There was also the issue of at least a three week wait for forged pistons to be in stock...

The engine has ~99k miles on it.

KN_TL

iTrader: (3)

skirt failure maybe
ring land failure seems to be a weakness
3 weeks for customs is way off, more like 4-6.
I would have given u a deal of the century.
good luck in whatever u decide!

RD_04TL

Kn_TL PM send

screaminz28

iTrader: (1)

The only issue is that if you have further engine issues, it could lead to having to replace EVERYTHING.

Even if what occurred was a fluke with regards to the skirt, the ring lands are a known weak spot. Are they at least going to take the existing pistons out and widen the ring end gap? If not, I'd say you should start saving your nickels for when the others do fail.

I don't want to take anything away from SpeedFactory as I'm sure they are top notch, and the quality of their work is excellent, but I'm kind of surprised that they didn't have both water/meth injection from the start (unless they strongly suggested it and you declined) and also the light for the oil scavenge pump. It's great that they have recommended so much stuff AFTER the fact, but those two items would be cheap insurance against larger catastrophe.

RD_04TL

If it's a known fact that the ring land is a weak spot what can be done as a preventative measure to avoid this kind of catastrophic failtures?