Recently built a new motor for my Integra. It currently has 1200 miles on the new build and specs are as follows...

-Ls block with eagle rods and upgraded cast pistons 81.5 mm
-Gsr head with upgraded valve springs(everything else is stock and has around 115k miles on it)
-ARP head studs
-Stock head gasket
-Drag Gen III turbo kit running at 18 psi
-All new gaskets and seal throughout motor(including valve guide seals)

In the last 2 days I've noticed smoke coming from my catch can setup at idle and a loss in power. No smoke is coming from the exhaust at any rpm including idle. Also no smoke under boost. Did a compression test and found cylinder 3 is at 100 psi while 1,2 and 4 are at 165 psi. Did a wet compression test on cylinder 3 and psi only increased to 110. This would lead me to believe its not the rings. I will performing a leak down test tomorrow so I'll be able to provide results from that if needed.

So my question is what could cause these symptoms besides piston rings? Burnt valves, valve guides, etc?

Any help will be much appreciated!!

 

ringlands. a leakdown test will tell you if you have a burnt valve.

 

Its hard to believe I could have a cracked ringland if there is no oil consumption and no signs of oil being burnt coming from the exhaust.

 

When I had my b16 turbo I broke the ringlands, it didn't smoke out the exhaust but the catch can was like crazy. Also it sounded like a Subaru.

 

Well you kinda hit the nail on the head. That sounds exactly like what I'm experiencing. Even the Subaru part lol. I guess its tear down #2. The sad part is that this engine is a rebuild from blowing the first motor last year...that motor also failed on the same cylinder. Have any ideas what could cause a sleeve to blow on one motor and then crack a ringland on the next?

 

First time it happen was on #1 cylinder boosted about 3 months at 10 psi 325 whp.

Then I ripped it down a changed the one piston and honed it in the car. lasted another 2 months before I broke #1 and #3.

Now I have a sleeve block with Cp piston, Have not had a problem in 3 years.

 

you wasted your time with cast pistons. next time get a set of forged pistons.

 

Thats pretty much what I expected. I guess I'll make plans to rebuild after I get other depts settled. Thanks for the advice!

Where I wasted my time is irrelevant at this point but thanks for you 'input'. I took my chances with the cast pistons bc I talked to several ppl that have had great success with them and I wanted to give them a try. If I actually wanted to take the time to blame one part of my build it would be Crome.

 

x2