After sorting the 5500 rpm "whoosh" screwups (flapping cold air scoop), re-tuning and doing a few runs, im still only doing 250 est WHP (DLL graphing, yeah not perfect, but im pretty anal on the input variables). Im down to zero knock at all loads/RPMS, but something is still up.
Time to put the new FG boost leak tester to good use Stripped out the intake components, fitted the leak tester and a (hand!!) pump. Got cracking and one good 'right arm workout 'later (no funny comments lads :P ), im up at 12 PSI. Well, I can hear the air pissing out. Took me a moment tnarrow it down - and yep, it is the throttle body seals that seem to be plaguing a few of us lately. No wonder my car is not going over 250!!!(The stock seals are rated to 7psi from factory (according to WORKS website) before they start to leak. According to my leak tester, my throttle body seals start pissing air (throttle closed) at 1 PSI. Its not too fast, but if I open the throttle, the pressure drops REAL fast. Like a BIG leak. Ah well, cant win em all
Im going to get the seals fixed and re-run the test. From what I can hear so far, thats my only leak to just under 13 PSI. Who knows whats going to show up when I get the pressure up to the top.
heres what I did, in case anyone else who wants to do this test, does not know:
- Unbolt the three bolds holding in the air box.
- Unclip the wiring to the MAF (the wire to the left, kinda underneath the air filter box, above intake piping)
- Unclip the jubilee clip holding the air box to the intake piping (left of airbox)
- Gently lift airbox up and wiggle with a bit of pressure to remove from intake piping. Set to one side, trying not to get any crap inside it from the ground
- undo two jubilee clips holding rubber pipe between right side LICP (intercooler exit pipe) and UICP. Remove hose (not a strictly necassary step, but makes it easier for you)
- unclip jubilee clip connecting BOV to intake piping. Do not remove BOV from UCIP !!! Remove BOV from intake piping.
- Unclip jubilee clip on tubo to intake piping. Wiggle loose from turbo and then remove the vacuum line from the far side of intake piping and remove the small BCS pipe from underside of intake piping.
- Remove intake piping
- connect boost leak tester to turbo inlet and screw down with jubilee clip
- Reconnect rubber hose between exit LICP and UICP and clamp down with jubilee clips
- Connect compressed air source to boost leak tester. I used an 80PSI rated hand pump. If you dont want to grow biceps like Arnie, then I would recommend a compressor for this.
- Begin pumping till you hit 10PSI on the gauge. Stop pumping, see if the boost drops and listen for hisses. Find out where any hisses are and try to rectify (remember to return the pressure system to relative atmosphere before un-clipping anything!)
- If no hisses, then keep pumping to 15 PSI. Rinse and repeat. No hisses? Go to 24 PSI.
- If you reach 24 PSI and it holds, congrats, your system is perfect! If not, find your leaks n fix em.
When putting it all back together, dont forget to put the airbox back in with the lid on. On more than one occasion, I have put the airbox back in with no lid on, only to find I gotta take it all out again as the clips (that hold the lid on) are stuck pointing straight down.
hope this helps a few of you.