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waiting for my leak down tester. I think I can do further diagnostics on Staturday.
the system does not built any pressure, but air comes out of the exhaust. If I block the connector hose before the throttle I can increase the pressure up to 15PSI than the BOV leaks. but I will remove the bov for testing next Saturday too.
the leak down tester didn`t arrived last week, so I checked it again. I turned the Engine to every point I thought I could catch a point where all valves are closed but allways the same. I also tried nickelndime method with the extentions but allways the same. air comes out to the spark plug holes or from the exhaust.
but I found the problem I was looking for, my exhaust manifold nuts were not tight. after retighten them the sound I mentioned was gone and the car pulls good for the current boost and mapping.
so everything seams fine but I`m still not able to built pressure during boost leak test ;-/
is it possible that I just cannot catch the position where all valves are closed because of the cams and timing?
if I catch the mittle of the second stroke on cyl 1
cyl 1 will compress - so all valves should be closed
cyl 2 will be in the power stroke = also valves should be closed
cyl 3 will be in the intake stroke = intake valves are open (ok as long as the exhaust valves are not leaking
cyl 4 will be in exhaust stroke = exhaust valves are open, intake care closed
but with timing and these cams I expect that the valve overlap will make the short moment where cyl 3 and 4 are not overlapping very hard to find.
HKS 272 the intake is already 1.0mm open 7.3° ATDC and exhaust 38.9° BBDC.
Camgears are adjusted for spool so much overlap
marks on the camgear:
EX = 3° Advanced
IN = 2° Retarded
We already went over everything except a leak down test, so, get that done and report back. You should be able to find a spot that builds decent pressure with those and cams and cam timing. I'm able to do it with my GSC S2's which have valves open long before and after your setup thanks to longer duration (about 20*).
puhh had not much time in the past weeks, but did the Leakdowntest on saturday.
first thing I noticed is that if I test cyl 4 the air was comming through cyl 3, ok that was really strange, I expected that the head or the headgasket was broken between this two cylinders but I moved on with testing, I tested cyl 2 and air was comming though cyl 4 (?!?!?!?!?!?) ok it seams as the air was moving though the intake manifold as these cyl had the intake valve open a bit duing testing, I`ve put a extention on the pistons to see if they are on TDC with the first testings.
so I removed the valve cover to see if the cams are pushing on the valves or not, I cranked the engine till no valve was pushed on each cylinder and did the leakdowntest on every cylinder again. and now every cylinder was leakproof. gauge says about 18-22% leak which is on the scaling very right (better) of the green bar. don`t think the tool is the best so I wouldn`t rely on this values, but on the leaking tests I couldn`t defnetly see and hear that there is a leak.
ok what I also noticed, I cannot get all valves closed, I cranked the engine by hand many times and there is allways one cylinder where IN and EX is slightly open at the same time.
Cam installation is fine.
cam gear timing is
IN 0°
EX 4° Advance
coun`t be that I`m the only one who has this problem with boost leak testing. I think HKS 272 are not that extreme rarely here.
Anytime I couldn't build pressure boost leak testing an Evo it was always this line. If you're EGR deleted may want double check everything is routed/capped off correctly
Thanks to razorlab on the pic he must have posted it 1000000 times on here over the years hahahaha!!
