My 2004 2.2L Inline-Pro Stage 1, 18-19PSI turbo setup currently has a 3mm head gasket. Twice recently, I noticed coolant loss after a full boost run, so it's quite possible the head gasket has failed. I understand the Inline Pro 3mm headgaskets are not all that reliable.

I'm considering the Mahle 9.5 to 1 "drop in" pistons, maybe some aftermarket rods, new con-rod bearings and a stock headgasket.

Since I have to pull the head anyway, can you guys think of a reason why I should not simply pull the pan, and install new pistons/rods/beaings/rings?

Thoughts?

Also, are the stock rods worth re-using? Possibly with better rod bolts. I've got the redline set at 8500. I have no idea how strong the stock rods are. Was simply thinking that it could be easier to have the rods/pistons/bearings/rings pre-assembled and simply drop them in.

Thanks!

 

The money question: What fuel?

 

Put a stock head gasket on and some head studs then get a retune. 18-19 psi is a joke for these motors.

 

If he's running on 91 pisswater he's going to have a bad time but agree.

 

Local fuel is rated at 93. However, a recent check I performed with a clear fuel can showed 1.3 gallons of regular comes out of the pump before I get the better fuel. So it's likely a real world 91-92.

The guys I know that are running the Inline Pro log manifold and stock compression are limited to far less boost and HP than I am running. In fact, without really good fuel, the stock compression would limit my setup to around 330HP. Equal length turbo headers do far better with the stock compression.

 

You have to worry about cylinder pressure and detonation, not power level. How aggressive is your tune currently and when do you encounter knock?


Have you considered meth?

 

If the head gasket has failed, chances are good that the cylinder walls are scored. In that case, a sleeved block will be required. Ask me how I know...

Tim

 

Not to derail this thread but how can you know this just by a visual check? I understand that there could be some residual transfer from pump to pump, but we are talking a few ounces maybe, not gallons. I question your findings. and if so why do you go back to this pump, its obviously broken if it indeed transfers 1.3 gal of the wrong OCT each switch over.

 

Not to derail this thread but how can you know this just by a visual check? I understand that there could be some residual transfer from pump to pump, but we are talking a few ounces maybe, not gallons. I question your findings. and if so why do you go back to this pump, its obviously broken if it indeed transfers 1.3 gal of the wrong OCT each switch over.
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My local Sunoco station has 3 octane selections, a single hose and a blending pump. The hose, filter, internal tubing (which is quite large) , the valve and manifold assembly have what ever fuel was last in it.

It's easy to see the color change from straw to bright yellow in my clear race jug. The color fully changes at 1.3 gallons. This makes sense when you consider that the 2 quart filter is on the output, and 8 foot internal tubing is 1 inch diameter stainless, volume about 1/3 gal. The hose contains about another 1/3 gallon. The internals of this particular pump add up to significant regular being pumped before premium comes out.

Since there are only 2 local stations, this one is the better choice. For quite some time I was simply filling up my clear race jug before topping off my car. But it leaked in the S2000's interior, so I stopped that.

Any more thoughts on my idea of pistons and rods while installing a stock head gasket. I am NOT reverting to stock compression. Florida is hot, hot, hot in the summer and detonation is always a problem.

 

Back to the question at hand. Does anybody think this is a worthwhile plan of action? I've looked at the cylinder walls with my borescope and I see no flaws. Prior to pulling the trigger on this plan, I'll obviously verify the block and cylinders are in good shape.

Seems like I could install nice parts for $1500 bucks and have a much tougher engine and better head gasket reliability.

This forum is strange. Over at the miata forums I'd have 40 excellent responses. Over here, people avoid the actual question and talk about fuel instead. Sorry, but pump gas and modest boost levels are not responsible for the Inline Pro head gasket failures. I'd like to avoid such head gasket troubles in the future.

Know that I'm an experienced mechanic, engineer and have been building and tuning turbo cars for 25 years.