http://www.youtube.com/watch?v=JrIOaWam3XA


Please let me know your thoughts.

 

is the noise under acceleration? or only on idle

Is the noise only when engine is warm? (nothing to hear when cold)

You know many tt engines have a noise on idle around 900 - 1100rpm ?

But on the right side on the car you can hear it is louder, so i think this engine is a little ill

 

Impossible to tell from a video... these motors can be noisy at the best of times... even if there is an issue could be cam related, lifter etc... don't rule out a rod though!!!

Best getting her checked out

 

It sounds like a slightly bent rod hitting the edge of the crank on rotation.

 

^^ ouch. Would that account for the rough idle? I would think valvetrain.

 

Sounds like that yup;( Does it change depending upon throttle/rpm input?

 

Very hard to tell, good luck with it!
You should take it in and have Sharkey and James look at it tomorrow.

Are you a boost junky and maybe not utilzing race gas?

Good luck with it!

 

Not really a boost junky. I had the boost controller always set to 1.1 bars and seldom going into the 1.2 bar area. The max boost on the Greddy read 1.14 bars. Previous logs for AF read a lambda average of around 0.83 or 12.2 AF ratio. After installing an 75mm IPD plenum and 75mm TB, I did a quick test drive. After warming up the engine, 1st and 2nd gear sprints were mind blowing since the car has never pulled this hard. I was smiling ear to ear. So much in fact I lowered the boost to only around 1 bar just to be safe. It was around 3AM and the temps were around 30 deg F, unusually cold for the SF bay area. The dew on the cars was actually frozen at the time. Then I did a couple of highway pulls still pulled really hard and power could definitely be felt on the mid-top range rpm level. When I pulled over to garage it for the night I could hear a ticking noise that started to get louder. So I'm stumped if it's a rod problem. Low temperatures alone couldn't have been the main culprit.

 

And your gasoline at the time in these cold temps??

 

The same gas I've always used...Chevron 91 octane. I checked the oil filter today per the recommendation of 6speeders to inspect for any metal shavings but saw of none. I'm going to get it pressure checked since it was also mentioned that it maybe a vacuum leak causing that sound but from what I observaed yesterday it sounds mechanical but I can't rule anything out at this point.

 

I have that tapping (lifters?) when the car is cold and then after a min or two it goes away. Is that bad? Oil level good etc.

 

Why in the hell did you swap the 3.6 for a Cummings ?

 

Sounds bad to me, but really hard to make the diagnosis online. Try using a stethescope and pinpoint the sound , you can get them for $10 at a medical supply store.

 

Sorry, that will not work on these motors when the rod is glancing against the crank.

 

any update on this ?