400+ WHP w/ Timing Belt two teeth off

[1TireFireTSi]

I've decided to share an interesting discovery about my car with the community. Feedback welcome.

I dropped my car off at the local DSM/Evo shop yesterday for a timing belt replacement. The mechanic verified TDC, pulled the cover off, and noticed the belt was installed 2 teeth off. Belt still untouched, we could see the reference marks weren't even close to lining up. After a few more preliminary checks to make sure it wasn't a fluke, it was clear this motor was way out of time (28 degrees at the cams). I believe it was 2 teeth over advanced, and I think the CAS was fully advanced as well.

This car dynoed 405whp and 378 lb ft of torque on a 16g/E85 tune using DSMlink V3 and I've been driving it since then, without any problems for over a year now. If it had slipped the belt a couple teeth, I certainly hadn't noticed a change in power or drivability, which leads me to think it's been out of time since I've owned it. It was hard to cold start, which I always attributed to the E85.

The new timing belt has been installed and with the motor back in time it's going back on the dyno in a couple hours to see if it'll need a new tune.

Here is the link to an E85 cold start I took a few days ago, before dropping it off at the shop. Full mod list in profile.

http://www.youtube.com/watch?v=aG5wxPArwJg

 

[importracr317]

Very interesting.....theres no way you could've "corrected" that much of a difference in ignition timing by adjusting the CAS, right? ....nevermind the actual cam timing....

 

[1TireFireTSi]

Very interesting.....theres no way you could've "corrected" that much of a difference in ignition timing by adjusting the CAS, right? ....nevermind the actual cam timing....

No I don't believe so.

-If I remember right, upon first getting the car on a dyno we determined it to be out of time, but upon adjusting the CAS and picking up 5 degrees advance it seemed to be putting down more appropriate dyno numbers. I could be wrong though, as this was well over a year ago.

 

[xxNocturnalxx]

Interested to see if the car will need a re-tune..

 

[clemu93]

Hmm for some reason, youtube says the video is blocked; do you have another link to the video?

 

[Blkknightgt]

Vid wont work, and post a vid of the new dyno run.

 

[1TireFireTSi]

Vid wont work, and post a vid of the new dyno run.

Video should work now, was set to private for some reason.

It ended up being a pretty disappointing day the dyno because before they could get a good baseline it started slipping the clutch so, it'll be a few weeks before I can get a better clutch in it and back on the dyno.

It does however sound a lot better now, even cold starts easier and idles better. It feels like it's got a bit more low end torque than before and seems more responsive when boost comes on.

I'll see about taking another video to compare the differences in RPM behavior and sound with the above video.

I'm still pretty amazed it was running so long, so well with the timing being off so far. I'm guessing the tune had a lot to do with it.

Interested to see if the car will need a re-tune..

It definitely needed the timing dialed in again after the cams were realigned. I imagine they made some adjustments in Link to compensate for the correction in timing as well. The only thing left to do at this point is get it back on the dyno and see how handicapped it's initial numbers were.

Here's a quick cold start video I took after the new timing belt was installed, and timing correctly set.

E85 Cold Start 2 - YouTube