Dyno Test

[AMG69]

I've been meaning to put my 6.9 on a dyno and generate some figures then Post them on here. Has anyone (on any model W116) done this before?  It would be interesting to have them all logged on the site to compare.....am I going to be first cab off the rank as it were?

[Des]

You are the only one here with a euro though aren't you Chris?

That gives you a small advantage over our choked Aussie models.


Another thought, could you have yours run with and without the air cleaner installed?

I'd imagine inside a workshop the car isn't going to suck in anything nasty to get stuck inside your injection system, unlike if you were running it on the road without the air cleaner installed.

That would at least give us an idea of how restrictive these air cleaners really are.

[raftel]

I dynoed my US model (#3895) 6.9 last November.  At the rear wheels, I measured 212 hp @ ~4100 rpm and 298 lb-ft torque @ 3000 rpm.  Air:Fuel was about 12:1 at these levels, so the warm up regulator was dumping a lot of fuel.  If I could lean the mixture out a bit, I'm sure I'd find even more power.  Timing was set to about 7 degrees BTDC, if memory serves.

Using correction factors backed out of the factory shop manual, that gives me 282 hp and 397 lb-ft respectively.  The 25% correction may sound high, I guess the drivetrain is not very efficient.  In any case, that is what the manual suggested.  I don't have it handy, but I can pull the reference if needed.

You might note that those numbers are almost spot-on with a Euro engine.  I found that odd too, but I can assure you that it is a US engine, complete with all the emissions junk - air pump, egr, cats, etc.

Robert

[Mercules]

Hey guys,

I have worked with a chassis dyno for a few years now - just feel there is a small point I should make... Every dyno in the world is calibrated differently... your car may pull 200hp on one guys dyno but only make 180hp on another - the thing about dynos is that they should be used essentially as a comparative tool.

If you do "before & after" runs with your car when performing modifications, you can attain a comparative result from the mods you made. If you and 10 buddies get your cars run back to back on the same dyno, you can settle the score on who has the most power.

Many factors like ambient air temp, drivetrain loss, fuel quality - even workshop altitude - can affect the final result of a dyno power run - in the end what you really want to know is how much power you MADE... not how much power you MAKE

Cheers - Cam

[CraigS]

Is that New Zealand ? 

Mine is also a Euro, which will be dyno'd in due course. As Cam says, it is about getting the maximum efficiency out of your engine. I did my 300b and the improvement in starting and torque was noticeable, not to mention fuel consumption. As cams wear, timing chains stretch, etc. etc., the factory specs for timing/tuning do not necessarily produce the optimal result, whereas a dyno will - at least in my experience.

[Des]

Mine also came from the Land of God Save The Queen

sorry.....I forgot about that old rust bucket

 

just kidding mate, sounds like she is going to be a car to admire when it is all finished