Maybe we are not going to miss out on all the fun effects as the Govt is looking at legalizing the "Weed". Fun times to be had puffing on a roll your own while sitting in a cloud of volatile fumes expelled from carburetor blow back. Should be able to get a bit of the flash bang "ooh, I feel so bad." ....![]()
Very well put and exactly my feeling.
My greatest fear, at least here, is if any of the above persons one day “doesn’t enjoy coming here and spend time and spread their know how” due to how they, or any one for that matter, are approached.
The “dinner party”-feeling and the possibility for n00bs trying the improve their 60 year old moped (that’s me) being able to get help and answers from world champions of the modern era...that’s totally unique. And it’s up to all of us to keep it that way.
My dyno setup had a 4' industrial fan that you'd want to wear a jacket in front of in winter, but it struggled to keep the temperature constant.
Don't you look at my accountant.
He's the only one I've got.
Yes it is. While Jan sat on the comfortable side of the double-glazed window, I was squatting next to the engine, wearing a welding helmet with clear glass, and earplugs and hearing protectors, and fiddled with the ignition. It was our first encounter with HCCI; it has taken us decades to understand what was going on back then.
In the absence of a LIKE button.
What Husa and AndreasL said!
Cheers, Daryl.
Either of these alterations are encouraged?
First of all, I am sorry for the excitement I may have caused. It was not my intention to step on anyones toes. English is not my native language, so I may not always pick the correct word or come across in the right tone so that everybody can understand what I am after and in which way.
Secondly, I knew about the possibility of louvering the test cell fans, but was wrong about the range. I thought that one could adjust by a couple of mbars (+5 / -5 or so), but not that it would be possible to hold the test cell pressure stable throughout the whole year. In that case, the argumentation chain above is invalid.
Thirdly, I am all for respect between board members, and utterly independent of their 'rank'. This means also taking your time to read the questions (in this case Tim_Ey's questions) properly and adressing the items asked if one decides to answer.
And lastly, I am curious now:
By how much / in which range can you control the test cell pressure in this way on an average test cell?
My point is, that ambient conditions and the way power has been corrected is a standard information on any dyno sheet. And it is vital if you would like to compare and classify different measurements. At least now we know that the famous RSA dyno chart shows 54 uncorrected ps(?) measured at 1013mbar , 27°C.. This would be about 52,6hp corrected (25% humidity assumed) if measured at the same ambient conditions on wobblys dyno which seems to correct by EWG standards (k=1,000 @ 990mbar / 25°C / rh 0%)
English is not my native language either. But I'd say your message came across. No hard feelings. My message is: you can ask anything, but you cannot demand it.
It depends on the capacity of the blower, of course. You can visibly warp the ceiling of some test cells just by juggling with the louvres; you'll get scared to death when you calculate the force acting on the ceiling. And I know of a case where somebody attempted to open a test cell door while a test was in progress. The door broke his wrist...I knew about the possibility of louvering the test cell fans, but was wrong about the range. I thought that one could adjust by a couple of mbars (+5 / -5 or so)...
I wouldn't dream of 'pulling rank'; I hate that kind of behaviour. But I do respect experience. I was lucky to work with the very best and I know nothing comes easy.I am all for respect between board members, and utterly independent of their 'rank'.
I don't know what an 'average test cell' is capable of, but I'd say that 40 mbar ought to be achievable. Wob, what's your opinion ?By how much / in which range can you control the test cell pressure in this way on an average test cell?
Of course it is vital information. In order to fully understand what you're looking at, you'd need not only know the ambient factors but also the engine coolant temperature and in fact all relevant engine data, like the set I posted as an example the other day, plus the mappings for rpm-throttle-ignition, rpm-throttle-powerjet and rpm-throttle-powervalve. All this information is accessible to the dyno operator, but it won't all fit on the graph. Besides, I was not trying to be comprehensive; I only wished to give an impression of things.My point is, that ambient conditions and the way power has been corrected is a standard information on any dyno sheet. And it is vital if you would like to compare and classify different measurements.
The standard values that you quote are new to me. I always went by standard conditions of 20°C (the Japanese use 15°C), 1013,25 mbar and 50% relative humidity.
As I wrote, SAE- and DIN-correction algorithms do not do justice to high-performance two-strokes.
I use the following correction algorithm, based on SAE 850085 (Eran Sher: A new practical model for the scavenging process) , SAE 930503, and my own findings.
corr.factor = (1013,25/Pdry)^(9/8)*((T+273)/(20+273))^(0,8) , where Pdry = actual pressure - partial H2O vapor pressure at actual temperature and relative humidity.
Andreas, I tested many times 1 alteration with different cut height, on similar Honda NS cylinders. This not changed max power, but rise torque at usual "dip zone" from 7000-8000 rpm.
Not tried 2 alteration, but this could be very good for piston ported engines. Hans Hummel always used interesting solutions on his cylinders for TZ.
In below pic, the 'holes' above the wristpin is shortcircuiting my aux exhaustports with the transfers, i have no exchuse, i just measured wrong and now i have this piston, brand new with altered location of the ringstops.
And to spare me a lot of search of a new piston(67mm) i thought i´d ask an insane question here with the guys that has tested it all, you guys.. =)
Is there any way, easy way of filling these holes?
As is now it 'puffs' quite bad into the aux exhaustports when spinning the engine without the head monted.
JB-Weld, Pour in polyurethane, pour in molten aluminium, anything?
Or just search whole world again for a suitable piston.....
if I were to fill it with JB-weld or anything else , I would first put a couple of pins in the side of each hole that would prevent the whole part of coming out in one piece.
There are currently 34 users browsing this thread. (0 members and 34 guests)
Bookmarks