Alright boys, the results are in!
There are a few considerations while looking at these:
- The results are taken in different countries at different times under different conditions
- We're making a reasonable assumption on Dyno consistency based on brand (Dyno Dynamics)
- I have modified some of the results under reasonable
Keeping that in mind, we can get started!
The first issue I had to overcome is to express my OEM reading as if it was measured on the last dyno that I used (Dyno Dynamics).
I started by measuring the differences between the OEM manifold and the prototype:
I then used that to calculate the percentage improvement from the OEM behaviour:
I then had to remove the (as yet) unexplained kink in my results. I had to do this otherwise I couldn't use my percentages to extrapolate the results.
After removing the kink in the curve, I was then able to extrapolate the OEM data to the Dyno Dynamics results. Using this I was able to plot the OEM results against the ITB (Prototype), Muffler, and 2.9L box:
It becomes immediately obvious how much any small losses from restricting the plenum volume are worth the trade for the extra torque from ~2500RPM
So how do I stack up against MLM and Warsteiner?
Well since it is obvious how much Warsteiner is ahead of us, I'll post this one with just MLM and my results:
The interesting thing is the weird thing is the extra power MLM seems to have in the sub 3000 RPM range. After that however you can see more expected results with my car having better mid-range performance, and slightly lower top-end. A couple of interesting things to note, is that I don't have a computer supporting my car yet, it is still OEM. I also haven't done anything to the exhaust other than the muffler - but I have achieved near identical results with less modification. This probably due to a combination of the M44 being a torquier engine, and the more effort put into optimising my design. An interesting observation to point out here, was that with the smaller volume, you can hear the induction note change in the very high RPM and the engine feels like it is beginning to choke right at the end, but the car felt like it didn't have enough RPM with the larger box. It would be interesting to see what I could hit with a proper tune. I also have the tapered runner to test, and running them with a slightly higher rpm and larger plenum volume could be substantial.
I also want to remind anyway, that my drivetrain losses are very high as I still have the OEM DMF. Just remembered that, thought I would throw it in before I forget!
Now, Warsteiner:
Obviously his heavily modified engine demolishes our bolt-ons. It would be concerning if it didn't. It is still a bit unusual that MLM has that high torque spike at the very low RPM. At about 5750 RPM, Warsteiner has a jump in power - which I believe will be the resonant mode from the shorter Dbilas runners. I would be willing to bet that if you ran the 42mm ITBs with a 45mm tapered trumpet that was a bit longer, you would see a jump in power around 5000 RPM and a higher peak power.
If I had to draw any conclusions from all this - which is hard to do with any confidence since this is indicative at best - it would be that Rama's kit is very well optimised. It would appear to achieve significant results for less parts and effort than MLM's equivalent performance.
I
really want to get my car tuned now![/list]
