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Old 09-30-2005, 09:38 PM   #16
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Here are pics of my timing mesuring tools.
You can see how the needle points to 35 degree.
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modified engines-stand1.jpg   modified engines-stand2.jpg  
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Old 09-30-2005, 09:47 PM   #17
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I'm no expert here in the crank area but looks like alot of material was removed from the crankshaft in the counterweight area does this engine have alot of vibration? Seems to me it would vibrate to some degree . Also all the smoothness would'nt let the fuel puddle to give it a forced induction action. Seems if I leave the area sorta porse where fuel will puddle then it seems to flow more fuel through the system. But thats just my opinion....?? Looks preety though!
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Old 09-30-2005, 10:01 PM   #18
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Quote:
Originally Posted by bbntc3
I'm no expert here in the crank area but looks like alot of material was removed from the crankshaft in the counterweight area does this engine have alot of vibration? Seems to me it would vibrate to some degree . Also all the smoothness would'nt let the fuel puddle to give it a forced induction action. Seems if I leave the area sorta porse where fuel will puddle then it seems to flow more fuel through the system. But thats just my opinion....?? Looks preety though!
Hey Bob! how is going?
it is not about how much it cut off (Please understand me right-I am not bashing anybodys work, I just try to discause the modding), it is about what will be balancing and how it will affect performance. We do cut opposite side of cranck, just for example as on picture.
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Old 09-30-2005, 11:05 PM   #19
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interesting stuff! one thing I've never been sure about is when I see talk of modified engines with much improved fuel mileage and increased power. I guess you could optimise the timing and such to get the best compromise but most talk of increased flow thanks to porting, cutting etc, helping it cram more 'fuel' and air into the cylinder. better power maybe but better mileage to boot??
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Old 10-01-2005, 01:50 AM   #20
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Hello Edward, you are craaaazyyyy

Hey, I got a simple question for you. When I put my degree wheel on my crank, it takes me forever to find BDC exactly.

I am pressing the piston down with a piece of wood and the put the wheel to 0 degrees.
Then I turn the crank about 90 degrees to the left and push the piston back down. I do the same to the opposite way.

Usually the wheel then will not stop at 0 degree, so I'm readjusting both ways until it does, which can take quite some time.

Is there a better way of doing it?
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Old 10-01-2005, 01:55 AM   #21
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Quote:
Originally Posted by Top Gun 777
will open some numbers if anybody wants to play with their hardware-induction open at 37 ABDC and close at 59 ATDC, exhaust 162, transfer120.
Hope this will help.
Edward
Are those values for your PS 12 or a NR based engine.

Doesn't the crank open a bit late? I always open mine at 30 -32 degrees, duration = 210 degrees with 160 exhaust.

One more question: How does the crank duration shift the power band?

My theory: Open earlier = more torque, close later = more rpm. True or flase?
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Old 10-01-2005, 04:22 AM   #22
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hi ed,
you work for timing not with my tool??
can you tell more about balancing the cranck.
i will make more with that fine tuning in the next season
dieter
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Old 10-01-2005, 04:26 AM   #23
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hi stefan,
242 ° einlass schließt ist ja ok, aber wie soll ich die 160 ° für den auslass verstehen. ich nehme derzeit eine auslasshöhe von 4,7 mm und das sind ca 79 °
dieter
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Old 10-01-2005, 06:34 AM   #24
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Quote:
Originally Posted by 4racer
hi stefan,
242 ° einlass schließt ist ja ok, aber wie soll ich die 160 ° für den auslass verstehen. ich nehme derzeit eine auslasshöhe von 4,7 mm und das sind ca 79 °
dieter
Hallo Dieter, gesamte Oeffnungsdauer vom Einlass ist bei Dir 79 x 2= 158 Grad

also fast das gleiche.

Der Kolben kommt runter von OT, oeffnet den Auslass fuer 80 Grad, geht ueber UT und schliesst dann den Auslass weitere 80 grad spaeter wieder = 160 Grad.

Ich hoffe das ist verstaendlich
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Old 10-01-2005, 06:35 AM   #25
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Quote:
Originally Posted by 4racer
hi ed,
you work for timing not with my tool??
can you tell more about balancing the cranck.
i will make more with that fine tuning in the next season
dieter
Dieter, was verwendest Du denn zum messen?

Kannst Du mir mal ein Bild schicken. Meine Scheibe ist ziemlich runter.

Danke
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Old 10-01-2005, 07:21 AM   #26
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achso messt ihr das
dieter
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Old 10-01-2005, 08:29 AM   #27
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Quote:
Originally Posted by Hesky
interesting stuff! one thing I've never been sure about is when I see talk of modified engines with much improved fuel mileage and increased power. I guess you could optimise the timing and such to get the best compromise but most talk of increased flow thanks to porting, cutting etc, helping it cram more 'fuel' and air into the cylinder. better power maybe but better mileage to boot??
Optimizing flow (by right timing , angles on ports, width of ports etc) is about to get more power. It is not about to put more fuel to combustion chamber-it is about to put right amount of mixture, at right velocity under optimum angle at right time. By changing induction timing you are regulating when (bottom end or top end ) you are getting right ammount. Just for exsample-earlier opening make your engine reacher on buttom end and later closing make engine reachier on very top RPM (which is really helpfull on top speed). Now the art is to find balance between power and fuel milage. It is not rocket since to get more power, it is rocket since to make solid 5 minuts from 1 tank. More progress goes in power less run time we are getting from 1 tank. It is already on 1/8 scale extra pit stop very common thing on very fast engines. If you have very good pit man-yuor pit stop just about 2-3 second. See Mike Swager and his pit man Harry-they work really solid and result is ammezing In Florida this year Winternats harry and mike made pit stop 3 second it was lost of time, but gain from power was much greater and Mike broke couple of track records-single lap and best qualifuer (25 laps). Eventualy everybody will come to the same techniques (if we want to go fast) and our result will depend on pit man by 99%.
Edward
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Old 10-01-2005, 08:35 AM   #28
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Hey Stefan.
No, these numbers are not for PS12, there was 25 to open and 75 to close. On pic I just showed how I work with protractor and pointer.
About get BDC-I do the same-jst the difference is, when I work on cranck-I use loos p/l set with new conrod (I can afford it ). So I am removing play from every (conrod on cranck pin, conrod/wrist pin/[iston) the rest the same as you.
Hey Dieter, I do use formulas, but when I work on designs of engines, when it comes to real metal I use protractor.
Edward
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Last edited by Top Gun 777; 10-01-2005 at 09:00 AM.
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Old 10-01-2005, 08:51 AM   #29
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Quote:
Originally Posted by stefan
One more question: How does the crank duration shift the power band?

My theory: Open earlier = more torque, close later = more rpm. True or flase?
As I sad before-later closing defenetly helps on top RPMs, but earlier opening is not quiete work like that. There is combination of exhuast timing and induction which shifting power band. Higher exhaust-less dwelf time when combustion pressure push piston down-less torq ( this is general rull). So balance between opening-closing-exhaust is shifting power band.
But again, just timing will not make engine run as fast as possible. Piston/liner assembly makes a lot of inturation (mechanical friction due to the slikines of piston material, tapering on sleeve which create extra friction etc) and here is another art to find best set up. I know that not many people can make their own piston/liner set (actualy it is only one guy can in the world), but defenetly there is big potential baried and our chalange is to bring everything to surface.
Edward
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Old 10-01-2005, 08:58 AM   #30
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Quote:
Originally Posted by 4racer
can you tell more about balancing the cranck.
i will make more with that fine tuning in the next season
dieter
Hey Dieter.
Balancing one of the biggest inturaption we do have on our engines. There are many theories around the globe use to make the best. If you see on pic that banch of holes we made on front of cranck-is one of them. Position and how much weight will go out is most important. I can't disclose in public forum the numbers-it is our intelect properties. Just I gave an idea where metal needs to be removed to tramnedosly improve power. Now it is up to single person to look for position and weight out. Sorry.
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