2.0LSVEK

I had an incident with my new engine and I am seeking advice on where to go from here.

I was advised by my shop to run high compression pistons to keep my low RPM power and also spool the turbo quicker. He said that it is recently common practice run forced induction engines with these specs.

B20VTEC
84.5MM Supertech pistons 11.5/1CR
Gt3076R
ID2000 injectors
Premium pump 93 octane

Tuning was going along but not great. My wastegate turned out to have a 16LB spring set in it. I was told this was making tuning difficult. He was able to tune the low RPM cam but when it crossed over to vtec we were either too rich or too lean and he would abort the run. Eventually he figured out "acceptable maps and settings" to cross over into vtec and did 2 WOT runs. At this point I noticed a coolant leak from the radiator cap. We checked the cap and the coolant level and all seemed ok. On the third WOT run the lower radiator hose was completely blown off the block and I suspected the head gasket had let go.

When I got home I pulled the plugs and saw a tiny bit of coolant in cylinder 3. I then pulled the head to replace the head gasket and noticed the piston damage.


I see my options as follows:

1. Replace all of the pistons with 9.5/1 CR and run premium gas.

2. Replace the damaged piston with another 11.5/1 CR piston and run lower boost and or use E85 fuel.

3. Determine that damage to the piston is only superficial and run my current piston set at lower boost settings and or E85 fuel.


Please look at the pics and tell me what you think should be done. Thanks!

Flr Power

Running 11.5CR piston at 16psi with 93 octane is a recipe for detonation. It's E85 territory. If you have access to E85 then use it. If not then go lower compression (below 10CR). It would be best to take out all pistons to inspect for damage.

Muckman

iTrader: (2)

I agree. I'm not sure why your tuner thought pump gasoline was adequate with that much compression and boost. Plus the compression helps spool is nonsense. I cannot believe they tried to tune that with a 16psi spring. So many red flags here.

boosted94gsr

Maybe get a new tuner along with those new pistons...

NotARaCist

iTrader: (1)

This. It sounds like he's even ******* up on tuning VTEC, which is some pretty 101 type ****.

luck4rmkc

iTrader: (2)

cylinder wall looks scuffed I wouldn't just slap another piston in there without a fresh hone...

accordturb96

its a sad day when you have to question the tuner and ask yourself wtf? isnt he supposed to know this??

F22Master

16psi on a 3076? With a stock sleeve b20??? Sounds like you are more lucky that you only had a little piston damage...

How much power are you trying to make? Obviously 16psi is too much for your setup. I think you could stay 11.5:1, but I would go down to a MAX 10psi spring. Maybe even 8. Even at that you should be well over 300whp, which is still well past the comfort zone of stock b20 sleeves...

accordturb96

well you have to think, this all occurred on the dyno in a short amount of time, that really enforces how much wear and tear this engine situation and tuning is creating in an incredibly short amount of time

2.0LSVEK

My block is Benson sleeved. I agree that the tuner doesn't seem to be competent and I will be taking my car to a tuner in Houston next time. The engine produced 440WHP and 319WTQ on the last dyno run. I am wanting to stay above 400WPH with this engine when it's all said and done. I have already re-arranged my spring set in the waste gate to bring the gate pressure to 9LBS.
Thanks for the replies.

AZ_CIVIC

iTrader: (1)

I run 9:1 compression CP pistons in my setup and don't have problems with power.

NotARaCist

iTrader: (1)

Good for you? I don't see how that's relevant to this thread at all.

accordturb96

you have little man syndrome ^^

If you read the OP he stated one of his options would be using lower compression pistons, so AZ CIVIC was informing him of his setup and verifying that it would work just fine.

NotARaCist

iTrader: (1)

And you don't know what little man syndrome is, if you think it in any way applies here. Raising compression is not about power at the top of the band. Raising compression is all about raising power UNDER the band. Higher compression, better torque curve, better power before boost. Simple as that.

EsotericImage

iTrader: (8)

Dayum.
pump gas on 11.5 is fine.. But adding boost on top


Its not the tuners fault you decided to run pump gas with your set up. this shop shouldve advised you, but they mightve figured you werent using pump gas..

Its the tuners fault for trying to tune it with pump gas in it. He should know better *if he knew wtf he was doing


Like stated before, Run a 8-10lb spring, and personally with this kind of power, I would run an EBC.

accordturb96

like I said. Im talking about you and your attitude. No need to treat people like **** for helping right? There ins't anything wrong with lower comp pistons and boost. No it doesn't fit your theory but that doesn't mean it doesn't work or isn't correct. Obviously his setup wasn't correct for what he was doing. A better tuner would have said no more on the fuel you're using or figured it out. Still, would you appreciate some **** *** attitude coming your way? most likley not

EsotericImage

iTrader: (8)

I smell a tempa-ban coming!

accordturb96

just standing up for people helping, Im not a fan of someone putting down people who are trying to help

2.0LSVEK

I am running an EBC. I do have access to E85 fuel also and I think I will go with that. The shop that helped my build this engine did specifically say that it would work with premium pump gas! And it might have with much lower boost. I should have done a lot more research before I went ahead and took his advice at face value. And the tuner should have been knowledgeable enough to avoid tuning with unsafe conditions. Sometimes we learn the hard way.
So Is there any way this piston could still be used? All of the other pistons appeared to be undamaged. I really am considering just assembling the engine with a new gasket and head studs and filling it up with E-85. Too risky?

accordturb96

well you're missing a chunk of piston if I see that correctly? Also it has made some change in the cylinder wall so you can imagine it would only become a bigger issue down the road.

NotARaCist

iTrader: (1)

Yeah, keep sticking it to the man regardless of context. I'm sure that'll end well for you. There's good advice, there's reasonable advice, and then there's bad advice. All of the above might be an attempt to help, but that doesn't mean you should coddle them all. Lowering compression is not the answer here. Better fuel, and a tuner that knows what he's doing is.

It definitely sounds like he just threw numbers at your EMS to see what stuck. Did he just say **** it, and start at 16 PSI? Did he really not have any lower springs laying around? How did he determine your VTEC point, or did he just stick it somewhere and say "good enough"? I'm no tuner, but I know enough to know he dun goof'd.

If you already have ARP head studs, you shouldn't need to replace them. Gasket is obviously up for replacement. As for the piston, I would take it out and have it inspected professionally. There might be damage you can't see, and that damage will absolutely **** on you if it decides to give out.

I don't know about B20 sleeves being limited to 300, but you should definitely get a lighter spring and take it to a real professional to have it done properly.

2.0LSVEK

It seemed like the tuner was just "throwing numbers" at my ECU. I'm no tuner either and I know that someone who has more tuning knowledge than I do is not necessarily qualified.

At the time of tuning neither I or the tuner knew that Tial had spring sets. I thought it was one spring in there. So we thought we couldn't lower the boost.

On a side note this is the second time I have had leaky head gaskets when reusing ARP head studs. On two separate engine builds I have had one time used ARP head studs not seal the head gasket. I followed all the cleaning and lubricant requirements and torque specs. Happened twice.

Also my block is sleeved so no sleeve issues for me.

AZ_CIVIC

iTrader: (1)

Don't worry the dude is an idiot, you don't need high compression to gain low end power when you're using a gt3076r turbo. That turbo is small and will spool very quick on its own.

Secondly yes the guy did mention that he was thinking about using lower compression pistons and I was just letting him know that he can use lower compression and still get nice low end power. But what would I know LOL.

Flr Power

Well, the Supertech pistons you are using is made of forged 4032 aluminum, so it is a little less tolerant to detonation. This means some of the pistons skirt could have been stressed too much and just waiting to fail. It's called metal fatigue and it can be very hard to predict the failure. If the skirt fails you going to end up with a free rod waiting to punch new holes through the block.

Now, sometimes people might want to save time or money by skipping steps but if any pistons fail, be prepared to start over again... Time and money.

E85 is a very good fuel but you will also need a very good tuner. Also, I always do a compression test before tuning any high hp set up. This gives me a good indication of the engine and helps me decide if I should tune or not.

accordturb96

yea you must be wrong! haha its alright bro this was a fine example. detonation caught up with the high compression. glad were on the same page