Track times - boost leak?

[Turbo 420a]

Well, I finally got a chance to go to the track today and get some times. Before leaving for the track I removed my subwoofer and spare tire, poured some octane booster in, and set boost to 9psi. On my first pass I launched perfectly (1.867 60ft) but let off of 3rd gear a little too soon before the end - almost a 100mph trap. I still managed a [email protected] with the first pass.

My second pass felt a lot slower and like something wasn't right, when I got the 15.3 timeslip I knew something wasn't right. During the next pass I checked my boost guage while at full boost in 3rd gear and it was only reading 5psi!!! I took the car to a road outside the track for some WOT test runs and see what was wrong. The turbo spooled up and provided 9psi for about half a second, then boost would drop down and stay at 5psi throughout the gear. I went back to the track and tried another run, but another 15 second ET resulted with the boost acting the same way.

Does this sound like it is probably just a boost leak somewhere in the plumbing? My only idea is this might be small crack in one of the rubber hose clamps and only leaks when it has enough force behind it to open up (such as 9PSI of boost). A few days before this my BOV popped off and was handeled quite a bit before being reconnected to the intake pipe. Could the BOV cause a leak in boost? If anyone has had this problem or any advice it would be much appreciated. If not then tomorow it's off and back on with all of the piping, uggg here I go again

Also, I added a new photo to the gallery of my car at the track today for those who want to take a look.

 

[GSX90]

Boost leak. Do the pressure leak test.

 

[siueclipse]

just make sure all your IC piping is tight and check the intake manifold welds.. hehe

nice run on 9lbs of boost though

 

[DSMNightmare]

OK that trap mph is insane for that low of an ET. That T3/T4 must kick hella ass in the first half of the 1/4 mile. Not to mention that sweet 60ft... did you use drag radials?

 

[Turbo 420a]

Like I said the trap speed was a result of me letting off the throttle a wee bit early in 3rd gear at the end of the run. No drag radials used... yet

Last week I removed my cat and installed a test pipe and I could really feel the difference it made for my spool up. Test pipes aren't a big deal in the logging town where I live in Washington. I say it's worth the risk to run a test pipe on the street, unless your in Cali where I wouldn't doubt police are known to crawl under imports just to check and see if you have a cat! If not you can always install it for the drags only. If I was still running my cat at the track I don't think I would have breaked into the 13's. Yes, it helped that much.

In order to be consistant with my launches it helped me to find a place to practice several times until I was satisfied. If you know of an empty road where you will not be disturbed or get in trouble, go there. Practice launching over and over again with the EXACT setup/boost you will be running at the track. And for the love of God burnout before staging to help your tires grip just that much more. Two teenagers sitting behind me on the stands at the drags asked me "Why do you always do those weak smokeshows before launching?" I explained to them why and figured they must have just tagged along with their friend today when he cut the springs on his Civic DX and put a Neuspeed sticker on the front

Originally posted by DSMNightmare
OK that trap mph is insane for that low of an ET. That T3/T4 must kick hella ass in the first half of the 1/4 mile. Not to mention that sweet 60ft... did you use drag radials?