oneyedjack

Well I finally got some time to post an introductory pic. I seem to be photo-challenged and don't have any really good pictures so I thought you might like the dyno graph instead. The dyno was done in December of 2008.

Car is a stock 2004 40th Anniversary edition. The engine suffered catastrophic failure in April and was replaced with a fresh crate engine. I might put the car back on the dyno once the new engine has some miles on it as a comparison.

Also, A big thank you to electriclizard for listening to my whine and advising me during the engine replacement.



Obligatory pic..

medtech

Well, so much for the X-51 being a bullet proof engine.

redridge

thats a nice curve....very linear power and constant torque. Congrats (I think) on the new engine.

jhbrennan

Nice looking car - I have a 40th too - any more info on the engine failure - cause, mileage, etc.? Was the crate engine an X51 too? Thanks.

oneyedjack

Love the new engine, still breaking it in. It was a bit of a nail biter with my warranty company but they covered most of the cost.

My engine suffered IMS failure at 44k. Failure occurred at startup, I never even put it under load. The dealership tow truck driver put it out of its misery by trying to drive it onto the flatbed. He only succeded in depositing 10qts of oil on the street in front of the house. The crate engine is an X-51.



Here is a picture of the revised "updated" factory IMS bearing. The larger nut is the tip off.

medtech

It that common for the dyno to be considerably lower than spec HP?

Jake Raby

These are rear wheel power evaluations.. That means a 15-20% loss of power through the drive train is normal.

Jack, glad to see you got this taken care of...

oneyedjack

Actually, I was quite pleased with the 302hp number. Most stock 3.6l M96 engines dyno around 280hp. So the 302 number for a 3.6l X-51 should be fairly accurate.

As Jake stated the numbers shown are rear wheel horspower. Manufacturers numbers are measured at the crank. The 15-20% loss is through the transmission and driveline.

DCP

Do you mind saying which warranty company?

dresler

?? Its pretty much the same engine, isn't it?

ArneeA

yep...same block...

russo

I replaced my original 996 engine with the x-51 and I am hard pressed to notice any difference what's so ever.

triode

Enjoy your 40th...very underrated car IMO.

Darren

Are all dynos created equal

2002 non-X51 996 with no mufflers and CAI:

Jake Raby

Every dyno is a tad different, but variables like tire pressures, strap tension, the last time the rollers were greased and rear camber and toe will also impact the results.

The Dyno jet is the most repeatable dyno by far.. They have the least variance between units of all makes and thats why I bought one... The way the dyno jet samples is simply speed Vs time, so it really can't be wrong..

These variables in the two X51s here are very close.. The temperature of the gear oil could make that difference in the two evaluations... As a developer my biggest challenge is killing variables that impact results, thats why the majority of my internal engine development is measured in one of our engine test cells, to remove the variables associated with the vehicle... even worn CV joints, brake drag and differential selections can impact the numbers at the wheels..