"Dyno" results

Post by **foggyjames** » 17 Apr 2006 01:36 am

Andy...I have been arguing the same corner myself for quite a long time on Turbobricks, but the general consensus seems to be that the basic increase in airflow measured by the AMM will give a coarse approximation to the correct mixture, albeit not as accurate as the precisely 'trimmed' off-load mixture provided by the lambda sensor. I would, of course, use ECUs from a B200F, which would get us into the right ball-park.

The main difference, so claim the knowledgable ones, is that the AMM measures air mass in grams, rather than the AFM on LE-Jet which purely measures flow in CFM. I don't see it myself...but...a stock B230F with a bolted on (big) turbo kit, just made ~270bhp at the wheels on stock LH2.4 (albeit with bigger injectors), and ~315bhp at the wheels with chipped LH. That doesn't happen with LE / Motronic. What I don't know is how healthy the AFRs were.

cheers

James

Post by **jtbo** » 17 Apr 2006 04:49 am

Those 300-serie injection models without lambda are using this flap type air mass meter and that flap is fully open from around mid revs and program uses predefined values so if we think about b200e, it is rather difficult to get fuelling correct with mods at high rpm & load.

However I don't see why to use stock ecu in modified engine while costs and trouble is same as Megasquirt for example ?!? Only if there happen already be that stock ecu it is reasonable to use it, in other cases I see it is waste of energy and money...

Ali, when you removed rear seats, did you compensate weight change to program?
Also I'm interested to know that did you had that cold/hot air flap on place also with original airfilter?

As I think that there is bit too much increase for airfilter only, my experience from no air filter to stock air filter without hot/cold flap and CAI is that there was no measureable difference, so everything was between error marginal.

Post by **Ali** » 17 Apr 2006 03:54 pm

Nah I didn't change the vehicle data at all as I wanted to see how much removing weight would show up on the graph, unfortunately I didn't get a test with just the air filter swapped over so I don't know how much difference it makes, I might well swap back to the A-cam at some point and get some runs to see how the graph looks but waaay too much uni work to do at the moment to start playing/breaking the car!
cheers
Ali

Post by **jtbo** » 17 Apr 2006 04:41 pm

Hmm, you can of course copy your car profile, change weight and no need to drive new run, just use sample you recorded with seats. Of course would need to weight rear seats first, but I think those might be somewhere around 15kg?
That is not very lot of difference, I guess.

Post by **jtbo** » 07 May 2006 11:21 am

Chris, I put values from your 1st B172K graph to Excel and used math yourvalue*0,76 and got correct torque, then I plotted it to graph and looked fine to me, but I can't figure out from what that much extra is coming.

Has anyone tested 1,4l engine? I could use that information for my rFactor volvomod

Post by **Ali** » 07 May 2006 01:17 pm

Afaik Adam (340glt) ordered the parts to set it up, not sure how far he's got yet but would be nice to see a 1.4 graph, i've put my a-cam back in so i'll try to get a new graph of that soon

Post by **Ali** » 07 May 2006 05:08 pm

Right well I went out and did a couple of runs, not exactly pleased with the results....

Post by **Ali** » 07 May 2006 05:18 pm

Having now compared the old results for the V-cam its not actually that bad my car just obviously makes s**t peak power!

Power curve comparing them:

But the difference in torque!!!!

Quite interesting that you can see the v-cam does more past about 4700rpm

Post by **SteveP** » 07 May 2006 05:28 pm

Hmm very interesting figures.. the power band makes sense as the V cam is supposed to be better at the top end, but the a cam walks over it in terms of torque!

Post by **jtbo** » 08 May 2006 02:49 am

Hmm, that is suprisingly little that v-cam does, I was thinking that it would pull much better at higher revs, but maybe it is not very good for NA engine then.

I would love to get my ignition sorted out so I would get past 5000rpm and to get decent graphs, but I have had no money for gas so no possible to get that problem sorted either.

K-Cam pulls as well from low but is not causing that dropoff so early after 5500rpm my torque curve started to slowly come down, but that may be also because of ignition.
Hopefully can get sorted money thing out of away soon

Post by **Chris_C** » 08 May 2006 01:05 pm

I'm going to try getting another run today/tomorrow to see what the difference leaning my car up has had, should be intresting, as it's not bogging anymore, it was a lot the last month, and a little when I did those runs.

Jani, does this mean the B172k rFactor car is infact Fake? I best buy the game

Post by **jtbo** » 08 May 2006 06:16 pm

Chris_C wrote:I'm going to try getting another run today/tomorrow to see what the difference leaning my car up has had, should be intresting, as it's not bogging anymore, it was a lot the last month, and a little when I did those runs.

Jani, does this mean the B172k rFactor car is infact Fake? I best buy the game

Well, I took that engine curve and calculated power from it so you could say that it is Fake, I have also many colours, so I may have right one too

Post by **Chris_C** » 08 May 2006 08:41 pm

Right, just been out for a run, and it reckons I'm running a tad less power and a lot less torque, which could be down to a number of things, now I'm not on the island anymore, I had to use a different road and recorder... But, still clean curves, and it feels a lot better, and I've done 80 miles on my £20, and still have half a tank

Click for bigger pictures:

Post by **SteveP** » 08 May 2006 08:46 pm

Looking more like reasonable B172k figures now - it seems that the island has some strange air or something

Post by **Carl** » 08 May 2006 09:10 pm

Chris - any chance we could give your little piece of kit a go in my car at some point? Would like to do a comparison before/after any engine change antics. And also see how a B230 runs on standard LE Jet hardware (just because I'm curious).