ESE's works engine tuner

[wobbly]

The range of ambient air pressure we see in NZ is in the range of 990 to 1020 mBar , and we had no trouble at all of " correcting " this to an arbitrary
1010 as this was a very common average condition.
Yes Frits the pressure over area can be huge - sometimes it was all but impossible to open the door into the cell from the control room.
25*C was chosen again, arbitrarily , as it was nice to be warm in the cell in mid winter and it needed little adjustment during most of summer.
Bottom line was that the conditions were close to static for all testing - important for comparative purposes when ambient changes have greater effect than the element being changed.

[TZ350]

In below pic, the 'holes' above the wristpin is shortcircuiting my aux exhaustports with the transfers, Is there any way, easy way of filling these holes?

JB-Weld, Pour in polyurethane, pour in molten aluminium, anything?

I have successfully glued the inside of the piston to block the bridge oiler holes.

Attachment 230863

The oiler holes for the exhaust bridge need plugging.

Attachment 230864

Normaly I would weld them but was persuaded to try gluing them with some super duper stuff that is as tough as shark shit.

Attachment 230866

The finished result.

Attachment 230865

[lodgernz]

I have successfully glued the inside of the piston to block the bridge oiler holes.

The stuff you mentioned: Is that it in the background, Belzona?

[peewee]

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?

Attachment 343232

Or just search whole world again for a suitable piston.....

maybe you can put pins from say a needle bearing. also maybe you can grind the side walls at the rear wider. even perhaps the roof at the rear taller. so basically the window gets larger as it goes toward the piston center. this would make it near impossible for epoxy to come out. also theres some over size piston for 250sx and such but I think are 68.5 mm.

[TZ350]

The stuff you mentioned: Is that it in the background, Belzona?

Yes .......

Attachment 232140

After 40+ dyno pulls at near 30hp the glue blocking the oiler holes is still there inside the piston..

[SwePatrick]

I have successfully glued the inside of the piston to block the bridge oiler holes.

Yes, i had a slight memory you did =)
Thanks for the links to the post, i´ll read up again =)

[SwePatrick]

maybe you can put pins from say a needle bearing. also maybe you can grind the side walls at the rear wider. even perhaps the roof at the rear taller. so basically the window gets larger as it goes toward the piston center. this would make it near impossible for epoxy to come out. also theres some over size piston for 250sx and such but I think are 68.5 mm.

I understand completely, i had that thought also

I can´t bore the cylinder any more, class rules

I was thinking something like this:
First, grind some grooves inside the pits,also grind the pit a bit larger then the opening and drill in some 'rebar' to secure it.
then shotblast the pits to get a rough clean surface.
Make a mold to get the pistonradious correct, drill small hole in the mold to pour the epoxi inside.
Heat up the piston some before as it tends to make the epoxi less viscous and grab on to the material better, say about 70-80 degrees.

Let it harden, and adjust after if necessery.

I had luck before with jb weld in other locations it seems to take quite good beating with heat, i have also tested added aluminium 'dust' from grinding aluminium into JB-weld, and by that got a very aluminiumlike material.
This engine is going away from methanol also as i want to test NOS instead

[Frits Overmars]

EWG standards (k=1,000 @ 990mbar / 25°C / rh 0%)

Haufen, I cannot figure this out: why on earth would one specify a standard relative humidity of zero percent? It would mean cooling all the incoming air in the test cell (and that is a lot!) down to 0°C in order to condense all H2O vapor, which would require a huge amount of energy, and consequently heating all that air up again to the specified ambient temperature, which would once more devour energy.
Jan Thiel and myself considered this approach in 1992 when we were working at Rumi, and it turned out that a separate transformer house would have to be installed for that to be possible. It would mean that 98% of all test facilities would not be able to meet the standard.

[husaberg]

Haufen, I cannot figure this out: why on earth would one specify a standard relative humidity of zero percent? It would mean cooling all the incoming air in the test cell (and that is a lot!) down to 0°C in order to condense all the


H2O vapor, which would require a huge amount of energy, and consequently heating all that air up again to the specified ambient temperature, which would once more devour energy.
Jan Thiel and myself considered this approach in 1992 when we were working at Rumi, and it turned out that a separate transformer house would have to be installed for that to be possible. It would mean that 98% of all test facilities would not be able to meet the standard.

I remember reading something Cameron wrote about the USA Kawasakis tuning operation was all done in the winter on the cold hell hole of a place.
They made huge HP in testing but for some reason not so much during summer and tended to have cooling issues.

[jamathi]

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.

We were very amazed I remember!
We were trying to make an ignition advance curve.....
You could change the timing 10° or more and nothing changed!!!!
Later, at Aprilia we had a gear-change problem.
Does this ever happen with kart engines?

[SwePatrick]

Haufen, I cannot figure this out: why on earth would one specify a standard relative humidity of zero percent? It would mean cooling all the incoming air in the test cell (and that is a lot!) down to 0°C in order to condense all H2O vapor, which would require a huge amount of energy, and consequently heating all that air up again to the specified ambient temperature, which would once more devour energy.
Jan Thiel and myself considered this approach in 1992 when we were working at Rumi, and it turned out that a separate transformer house would have to be installed for that to be possible. It would mean that 98% of all test facilities would not be able to meet the standard.

You don´t copy the exact given enviroment in the dynocell just because the problems involved as you mention.
You just compensate against that 'standard day' that would be a perfect day, from your numbers on your mediocre day

If dynoing 30hp on a bad day, the correction says what it might produce that 'perfect day', just to beeing able to compare to others.

[andreas]

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.

Yes I remember seeing H Hummels cylinders. I think in your pic 1, and probably 2 (as a double) is the second alt. Here is the same on an old cylinder where things went too far.

Warning: Photo is not for sensitive viewers.

[Haufen]

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?

I have successfully done this in the past with a product called scotch weld by manufacturer 3m. You roughen up the piston (do undercuts if you can), clamp an aluminium stripe around it (pour it in soapy water before so that it does not stick as much to the epoxy - use spit if you forgot to prepare the soapy water), then put it in the oven to dry and harden (@120-150°C iirc). Before use, do re-work on the new outer shape of the piston if required.

I did several of these and all held up perfectly well for many hours at full load on the dyno on an engine with about 12k red line rpm.

Today, I would, however, roll a small aluminum sheet, cut out the required shape and have it laser welded to the piston.

Haufen, I cannot figure this out: why on earth would one specify a standard relative humidity of zero percent? It would mean cooling all the incoming air in the test cell (and that is a lot!) down to 0°C in order to condense all H2O vapor, which would require a huge amount of energy, and consequently heating all that air up again to the specified ambient temperature, which would once more devour energy.
Jan Thiel and myself considered this approach in 1992 when we were working at Rumi, and it turned out that a separate transformer house would have to be installed for that to be possible. It would mean that 98% of all test facilities would not be able to meet the standard.

Yes that's true. Fortunately, as pointed out be SwePatrick, you don't have to reproduce the exact target conditions, just get as close as you can. The measurement will then be 'valid' if the correction factor is between 0,96 and 1,06 (in EWG there may be other limits for other standards).

-----------

BTW, seems like wobbly is only around 2 hp away from the RSA with his KZ engine, despite all the limitations in the KZ rulebook. Pretty cool stuff!

(I got these number using the EWG standard to reverse - calculate the performance his KZ engine might have had when tested under the same ambient conditions as the RSA (and an assumed 25% humidity) the KZ would be at 51,9 and the RSA at 54 - both measured under the ambient conditions from wobbly's last dyno chart would leave the KZ at 50,5 and put the RSA at 52,6).

[peewee]

I can´t bore the cylinder any more, class rules

it seems like millenium once told me they could apply plating to .36mm thick. this may let you go back to any common 66.4mm 250 piston. other wise devcon titanium putty may be the way to go

[katinas]

Detail pictures of KR 500 1979 crankcase

https://www.ebay.co.uk/itm/Kawasaki-...EAAOSwMcZc3Z~e