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Old 11-30-2014, 01:14 PM   #1
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Default just a thought, why is?

Just thought of something;

You have all theese engine gurus out there witch does very good work. Ports can be altered, cranktimes can be altered, combustionchamber can be altered, pretty much evrything exept, metalurgy and to some extent, crankcase volume, so:

If it is only timings balance factor of the crank and combustion chamber, why is there still some engines giving better torque or higher rpm than others.? It must come down to metalurgy, well comrod length is something that is not so easy to alter..
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Old 11-30-2014, 08:43 PM   #2
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Just thought of something;

You have all theese engine gurus out there witch does very good work. Ports can be altered, cranktimes can be altered, combustionchamber can be altered, pretty much evrything exept, metalurgy and to some extent, crankcase volume, so:

If it is only timings balance factor of the crank and combustion chamber, why is there still some engines giving better torque or higher rpm than others.? It must come down to metalurgy, well comrod length is something that is not so easy to alter..
Its a combination of everything that you mentioned, its not one component. Its also designer philosophy, where on the power band the designer wants the power to be made. I do believe that the metallurgy of the piston plays a role...
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Old 12-01-2014, 03:40 PM   #3
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The tolerances and materials used are a lot more important into making a really fast engine.
How the bearings are aligned in the crankcase, how much the bearings are compressed in the crankcase, is the piston/sleeve absolutely perpendicular to the crankshaft.
If you have a good crankcase it's worth it to keep rebuilding it, it can make a pretty big difference.

All the polishing and grinding is mostly useless show stuff which only destroys the fuel consumption.
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Old 12-01-2014, 04:58 PM   #4
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Most important is a perfect match of the expansion rates of the piston and sleeve so the perfect fit is secure with a large window of temperature. (In the Fusion-X topic special team pistons are mentioned)
We have played a lot with different piston materials in a non changed sleeve and you can notice a lot in difference. If they do not match a lot you will notice a variable power/performance.

Perfect alignment and low tolerances probably taken from the first batch after renwing all toolbits and a fresh alignment. And maybe also on made a lower speed or more steps to get a lower tolerance and a better alignment.

A better combustion chamber, for sure when it is optimised to the altitude of the event to get the lowest possible head clearance.

And there are different carburator needles to get a better performance.

If you are a manufacturer and do want to have the best for your top driver(s) you can think of everything high tech like F1 crankshaft steel which is light and can be made lighter and balanced perfectly. Low friction bushings, special high grade bearings, berylium pistons etc.
Sounds to advanced but it is possible...
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Old 12-04-2014, 02:01 PM   #5
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If you are a manufacturer and do want to have the best for your top driver(s) you can think of everything high tech like F1 crankshaft steel which is light and can be made lighter and balanced perfectly. Low friction bushings, special high grade bearings, berylium pistons etc.
Sounds to advanced but it is possible...
F1 crankshaft steel?
Perfect balance...single cylinder?

You can make things work within limitations...there will always be a compromise...you can not have the best of everything.
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Old 12-04-2014, 03:10 PM   #6
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True that a single cilinder is not easy to balance but balancing seems important, Picco also did make a step in performance by adding balance weights.

Yes, there is a special steel used for the crankshafts in F1 engines, it is very tough and light material. It needs a hardening proces in several steps to get the best out of it but then you have the best crankshaft you can imagine. An 14mm crankshaft can be easy drilled out to 12mm or even larger.

To think very extreme you could even use a high grade titanium

(btw, a titanium rod is not lighter but is unbreakable)
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Old 12-04-2014, 05:47 PM   #7
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True that a single cilinder is not easy to balance but balancing seems important, Picco also did make a step in performance by adding balance weights.

Yes, there is a special steel used for the crankshafts in F1 engines, it is very tough and light material. It needs a hardening proces in several steps to get the best out of it but then you have the best crankshaft you can imagine. An 14mm crankshaft can be easy drilled out to 12mm or even larger.

To think very extreme you could even use a high grade titanium

(btw, a titanium rod is not lighter but is unbreakable)
But it can be made lighter while maintaining the same strength as the aluminum one. The problem is that titanium doesn't like heat...
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Old 12-04-2014, 11:54 PM   #8
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No, it can not be made lighter, Titanium has more flex than aluminium and flex in the rod is not good.
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Old 12-05-2014, 08:55 AM   #9
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True that a single cilinder is not easy to balance but balancing seems important, Picco also did make a step in performance by adding balance weights.

Yes, there is a special steel used for the crankshafts in F1 engines, it is very tough and light material. It needs a hardening proces in several steps to get the best out of it but then you have the best crankshaft you can imagine.
Would I be right to think that any engine will require a different balance factor to operate optimally pertaining to the rpm?
An engine with low timing made to create torque will require a different balance compared to a screamer?

Have you got any more in-depth information about the F1 steel please?
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Old 12-05-2014, 11:49 AM   #10
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Yes, every amount of unbalanced weight has its own frequency because the combustion stroke is making the throttle depending counterweight.

I can not tell a lot about that steel. My sponsor could get an hand on a small piece trough contacts in the motorsports. All I know it komes with a huge spec sheet and manual how to treat it.
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Old 12-05-2014, 03:30 PM   #11
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Would I be right to think that any engine will require a different balance factor to operate optimally pertaining to the rpm?
An engine with low timing made to create torque will require a different balance compared to a screamer?

Have you got any more in-depth information about the F1 steel please?
A single cilinder engine can only be fully balanced for one specific rpm.
Ofcourse you can get quite close for a certain range, limiting vibrations as much as possible. This is what's being done at the moment.

There are several steels used for high end crankshafts.

I believe they first used a maraging steel, but this is now banned to save costs.
http://www.smithshp.com/metals/maraging-steels.htm#

Right now they basically use a very high quality tool steel which is hardened by nitrating it.
I know this company supplies steels which are used by most F1 teams:
http://www.bohler-edelstahl.com/engl...5_ENG_HTML.php
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Old 12-14-2014, 04:10 PM   #12
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There are several steels used for high end crankshafts.

I believe they first used a maraging steel, but this is now banned to save costs.
http://www.smithshp.com/metals/maraging-steels.htm#

Right now they basically use a very high quality tool steel which is hardened by nitrating it.
I know this company supplies steels which are used by most F1 teams:
http://www.bohler-edelstahl.com/engl...5_ENG_HTML.php
Thank you for the links.
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