S124 M113 V8 turbo Dyno session 1 @ DW TechSolutions

We had a long day with the first part of the rev range very good results but after 4500RPM less results.  To begin with i use as a base fuel 95octane.  this a 95 octane rating with E10   at the moment i measure 8.8% ethanol in the fuel.   This fuel is the lowest octane rating you can buy.  Reason to use this fuel is that if i want to use this car for a roadtrip or else.  That i can get everywhere this fuel.   98 octane is not for sale at every fuel station in the netherlands.    And because im also want to run flexfuel  this is for me the best starting point.

Below in the dyno graph  we had a peak boost of 165KPA of  0.65 bar or 9,55 psi boost .   i got 680NM @ 2944 RPM and 389HP at 4083RPM. But after this the the graph gets weird.  after peak HP it is going a little down but the oem 5,0 in NA from should have peak HP at 5600RPM. so there should be more to get.

the thing is the car is also after 4500rpm making boost .  but a little lower at the rev range around 0,6 bar or just under.  but the power output is strange.   Daniel from DW  mentioned he had no indiation for real misfire’s because the lambda value’s staying normal and where not going lean.  This mostly an indiation.

When we lower the boost under 0,5  the graph is getting more normall.

So i had some contact with some people around me that also have knowledge about these engine’s  and tuning .  and i really want to thank then for support and thinking with me on this .

on some discussions we came to the conclusion that misfire could not be the case because the hardware im using can handle much more. and is proven on this .  sparkplugs and igniton coils.  the settings on this look al good.  there are enough examples where these make over 900hp on m113k engine’s

at the moment im making under 50hp per cyl  and most stress is where torque is at peak and whe where already over this point.

So next.  just befor ending the day we made 1 power run and let the engien cam back to idle and shut it down.    i took out the spark plugs on all cylinders .   on bank 2, this is driver side cylidner 5-8   the sparkplugs looking good all the same nothing to see.  on bank 1 the plugs where dark brown to a little black.  This could be something.

when i drove the car for the first time cruising over 100kph this ia 2000rpm and higher the engine has more vibrations.  i first only suspect the engine mounts.   but also @ idle there is a slight constant vibration.   Now with al this in place.   We suspect something the cam timing on bank 1 .

So  this is for the next video. i will go investigate this and check everything i can

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