RedLineS2k10

AS u may have seen from my previous post, i had smoke from the catch can like the other guy. The dipstick shot straight out of the head shooting oil every where on the dyno, went to start the car back up and the smoke starting coming from the catch can. Pulled head off and everything looks perfect. The head looks like it could use a day at the machine shop (valve stem seals, etc). My compression was off..190psi was the highest i hit, but the guy didnt do the best compression test.im not quite sure what the compression is suppose to be because its a 2.4l (h22 pistons) with a stock head gasket at 10:7. The cylinder walls looks spotless, the pistons looks great. The head gasket looked a little warped, but besides that it everything else looks great. So its either a $100 fix or a $1000 fix for new rings, bearings, etc. I also have to pull the motor to check the pistons because the cross member on the s13 runs right below the oil pan, and the swar bar is so close u could barelt get a piece of paper through it. SO what do u think guys, head gasket or piston rings? I have pictures to post if anybody can spot something out of the oridinary. Thanks!

P.S car is 2.4L with gt28rs. "disco potato"

rob!

well to be honest you should have diagnosed this while the head was still on. You should have done a leakdown test to test where you are losing compression. There is ways to tell by doing a compression test to tell if you are losing compression through the head or block. you say 190 is the highest what were the low numbers?

Seems like you have a lot of blow by so id imagine your rings arents in the best shape. valve guide seals would cause a lot of smoke out of the exhaust.

RedLineS2k10

And thats where i made the mistake because the tuner and my buddy said rings. Then i had asked around a little more i started hearing head gasket. When i pull the motor, do the bearings along with the rings have to replaced. These rings are $167 a set for the h22 pistons.Does anybody know of a good place besides honda to gert a set of rings and bearings? Does any work need to be done to the crankshaft in this process?

Compression was:
1-90
2-135
3-190
4-85

>When the compression test was done, the guy barely tried to crank the motor, he let it crank for a half a second and read me these results.

Spoolin

Majestic Honda

AusS2000

You don't necessarily need to replace the bearings and you only need crank work if it's marked.

If the engine is low mileage and didn't spin a bearing then there is no reason to replace bearings. If it's high mileage or suffered from oil starvation and bearing damage then you should.

ZLFAB

dout that its in the bottem end. those numbers are aweful low to not have skoreing on the cyclinder walls.

Im thinking that its in the head, valve seals and get a valve job and throw it back together.

RedLineS2k10

When i first got the car it had a leaky injector, and one was clogged. Cylinder one valves were leaky, (black gunk on 2 of them). I sent the injectors out to RC for cleaning. i would get a little oil blow by inside the turbo after driving. There is NO SCUFFING OR BLOW BY on my cylinder walls. The bottom end looks cherry. The pistons are H22 and CPW coated. The motor has barely even 1000 miles on it. Design craft built the car in 07 to finish the formula D season. The car only saw 4 events. It was originally tuned at 350hp,360tq. which is extremely conservative for this setup. Ive only driven it 4-5 times. THe car has barely even seen the track. The head does look a bit nasty underneath as ull see in the photos.

chris_barry

Pull the pistons and look at the rings. if not rock the piston around and look closely a the rings. There should only be 1 gap in the top ring. if you have more that is your problem.

Apart from the rings, the only other common way the crankcase will get under pressure is boost finding its way through the PCV valve or main breather.

There is a possibility that boost is finding its way past the inlet valve guides into the rocker cover, but your guides and seals would have to be in really bad condition.

I have also seen this happen where new guides have been fitted and there is a leak between the outside of the guides and head. This normally shows up in a truckload of oil getting sucked down beside the guides when the throttle is closed.

RedLineS2k10

Well the tuner (not mentioning any names) turned the boost up on a gt28rs to 22psi..and then he turned it down to 19 and popped went the dipstick. Steam was pouring out of the head when i took the oil cap off, and was getting tons of smoke from catch can. To be completely honest im not quite sure what ur talking about --------)

"There is a possibility that boost is finding its way past the inlet valve guides into the rocker cover, but your guides and seals would have to be in really bad condition."

"I have also seen this happen where new guides have been fitted and there is a leak between the outside of the guides and head. This normally shows up in a truckload of oil getting sucked down beside the guides when the throttle is closed."

Very new to having a boosted car and learning about all of this. Thanks in advance guys

_holeshot_

22psi is out the compressor range for a gt28, which is probably why he lowered it to 19, I doubt a turbo that small held pressure to redline though, probably fell off to 13 or less. But it does sound like the rings are toast, when the motor was built how large was the ring end gap? Too small of ring gap may lead to ring breakage and too large end gap can also damage the rings

also check the gap difference between the top and second ring, general rule of thumb is .002" to .003" difference in gap from top to second ring, any closer than that can cause a pressure build up between the two rings that will blow down into the crankcase