babybaluga32 Posted April 5, 2011 Share Posted April 5, 2011 [ame=http://www.youtube.com/watch?v=jEwa_vM22Q4] compression test[/ame] The video is consistent on all 4 cylinders. 125psi and they all jump in the same increments. Is that good? When I floor it, go over 4500rpms then let off the gas, a huge cloud of smoke comes out (Blueish white). Perhaps it is the rings needing to seat longer, but its been about 800 miles. Link to comment Share on other sites More sharing options...
Baddog Posted April 6, 2011 Share Posted April 6, 2011 125 is low. Mine is 160 across all 4. My friends OB Sport put out 185 across all cylinders. Link to comment Share on other sites More sharing options...
I Donated broknindarkagain Posted April 6, 2011 I Donated Share Posted April 6, 2011 did you rebuild? hone/bore the cylinders? -broknindarkagain My Current Project - Click Here COME AND TAKE IT "The only thing necessary for the triumph of evil is for good men to do nothing." Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 I honed all of them and obviously put new rings on. All guides have new seals. Bent valves were replaced too. Would the heads contribute to low compression or just the rings? I changed my oil around 600 to full synthetic 5w 30. Before that I used plain jane 5w 30 . Link to comment Share on other sites More sharing options...
Baddog Posted April 6, 2011 Share Posted April 6, 2011 Both. Valves could cause it if they weren't installed properly. And rings. Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 Rings were installed exactly like the diagram in my manual. How could valves be installed improperly? Link to comment Share on other sites More sharing options...
Baddog Posted April 6, 2011 Share Posted April 6, 2011 Couldn't tell you. But I know rings and valves are the biggest causes for low compression. Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 Would bent valve guides or broken valve seals cause it? The valves were all to spec on the amount of acceptable 'wall width' Is it common for different brand compressions gauges to show higher and lower numbers than others ? Link to comment Share on other sites More sharing options...
Baddog Posted April 6, 2011 Share Posted April 6, 2011 Bent valve guides possibly. I am not the one to ask about all of that. I do know when you redid the heads you should have pour gasoline on them to make sure they were sealing properly. Compression gauges could be different just like every tool out there. Link to comment Share on other sites More sharing options...
I Donated broknindarkagain Posted April 6, 2011 I Donated Share Posted April 6, 2011 did you torque down the head properly? clean the deck to be spotless before you put the head on? if the headgasket didn't seal right, then you will have compression problems -broknindarkagain My Current Project - Click Here COME AND TAKE IT "The only thing necessary for the triumph of evil is for good men to do nothing." Link to comment Share on other sites More sharing options...
Lookatmyrust Posted April 6, 2011 Share Posted April 6, 2011 what the compression ratio? could that affect the reading from stock form? Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 it was 9.8:1 or 10:1, ive never heard for sure, but I have ej22t pistons in. which makes it around 8.5 ive heard. They were torqued PERFECTLY! I took my time! It was cleaned before I put the heads on to. Link to comment Share on other sites More sharing options...
Lookatmyrust Posted April 6, 2011 Share Posted April 6, 2011 could the CR make the difference.. lets do some math. how much volume is there are tdc and bdc. do the math and you can figure out what the compression would be in a perfect seal. Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 Im not very good at math! Link to comment Share on other sites More sharing options...
johnegg Posted April 6, 2011 Share Posted April 6, 2011 how does it run?? Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 It sounds like a really quiet helicopter, I think that is because of an exhaust leak though, if that could be related in some way. The only thing i have noticed is when I slowly accelerate and get to 3k it seems to not rise as easy for a few hundred rpms, its kind of bumpy/sluggish. Other then that it seems to run fine. Link to comment Share on other sites More sharing options...
johnegg Posted April 6, 2011 Share Posted April 6, 2011 it is hard to imagine that using turbo pistons would cause a compression drop from 165 to 125, but maybe. and if lower compression is what you want in order to boost then you sure got it. the good news is that all 4 are the same. it is also hard to imagine that an intallation error would be so consistent across all cylinders. wrong rings maybe but not an install error. why did you opt for turbo pistons? what were you hoping to accomplish? Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 Its turboed and wanted it to be lower. Arent STI's compression around 8.5:1? This link says that 125-130 is good. http://www.iwsti.com/forums/2-5-liter-litre-factory-motor/109593-06-sti-compression-test-results.html Link to comment Share on other sites More sharing options...
nmd003 Posted April 6, 2011 Share Posted April 6, 2011 Based on CR alone, switching to the ej22t pistons makes for a 15% drop in compression. You're at roughly 20% below 160 at 125, but there are other things to account for as well that might make a difference. Anyway, there's some math on it; I think with that and according to the link, you're probably right where you should be. Link to comment Share on other sites More sharing options...
johnegg Posted April 6, 2011 Share Posted April 6, 2011 This link says that 125-130 is good. cool, it's fixed. NEXT! Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 That link is for a 2.5l does that make a difference too? Mine is just a 2.2. Hmmm what could be burning oil though?? I should say, what would me heads be doing wrong? How would I check my turbo oil seal? . Link to comment Share on other sites More sharing options...
Mega Users seabass07 Posted April 6, 2011 Mega Users Share Posted April 6, 2011 You can look for oil in the intercooler or downpipe. If enough is leaking from the turbo to cause smoke out the exhaust, then there should be plenty of oil in the intercooler and inlet or the down pipe. If it's effecting the way the car runs, then it's probably in the intercooler. I'd find it hard to believe that all 4 cylinders are leaking exactly the same amount of air during the compression test. The compression is probably fine. Link to comment Share on other sites More sharing options...
babybaluga32 Posted April 6, 2011 Author Share Posted April 6, 2011 I noticed it has been slightly oily before, but I will check again, that was also pre rebuild when it did not burn any oil. Is it age that would cause it to fail + the fact that it boosts 2.5x more than stock? Link to comment Share on other sites More sharing options...
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