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Having done some actual testing to see the effects on weight reduction in regards to hp. I have found that there are substantial gains to be made if weight is removed from the rods and the pistons. At one point a few years ago we made a titanium rod forging and toyed around with making an affordable set of titanium rods for the B and K engines. Unfortunately titanium prices more than tripled during a 1 year time frame and the prices we would have to charge rose to a level that people in this industry simply wouldn’t be able to afford.

Doing engine dyno testing on a b18c engine. A 140 gram weight reduction per cylinder on each con rod yielded a 5 hp peak gain. Mind you this was under the same load and the same motor, the only change was the con rod weight. Even more significant than the 5 peak hp gain was the 13hp gain at 800 rpms after peak power. The power curve basically flat lined after it peaked, where as the heavier steel rods would taper off much faster.

As rpm increases there is also an increase in the amount of force/hp required to change the direction of the piston and rod. The heavier the piston and rod the more force that it wasted to change its direction. The crank shaft also has centrifugal force that acts on it. If the weight can be reduced there will be less force required to change its speed or rate of acceleration.

For me its really strange to see people buy aftermarket rods that weigh the same or more than stock rods. There is no gain what so ever and if the rod is heavier then you actually loose something. The stock rods are plenty strong and as long as you don’t do stupid things like over rev or rev beyond what is needed, then they really don’t have any problems. Aggressive marketing has trained people to believe that they need to replace certain parts that don’t really offer any benefits.

As far as rod materials and titanium rods go i have concluded that the 6AL4V titanium grade isnt suitable for connecting rods. There are other grades that are suitable but the cost is more as well. 6AL4V lacks the tensile strength to provide adequate longevity for long term use. For short term use its fine just like aluminum.

There are ways to make 6Al4V adequate but it requires reducing the weight of the pistons. this reduces the amount of strength required to hold on to it at high RPMs.

4340 steel can be heat treated to 250,000 psi TS (tensile strength) normal 6Al4v is only 110,000 psi TS. Although 6al4v can be heat treated to 160,000 psi TS it rarely is. There are grades of steel such as 300m that can be heat treated to over 300,000 psi TS. 300M costs a 3rd of what titanium costs but it weighs twice as much. So....... it’s really only about 30% less to make than titanium after these factors or taken into place. Also these materials are equally difficult to machine and the cutter life is greatly reduced.

Few people spend the money or have the money to spend to buy the optimal part. so they end up settling for what they can afford. This is part of the reason you don’t see these "exotic" parts available, people simply can’t afford them.

If I do an engine for my self 9 times out of 10 I use the crower maxi lite rod. They are about 100 grams lighter than the stock rods. Cost is about 700ish a set. I have used them for about 10 years and never had any problems with them. They weigh about 400 grams ish. Cunningham also makes a really nice rod that weighs about the same and is priced similarly.

Weight reduction, no matter where it’s applied has numerous benefits.

better gas miliage

Tobom vlada sekta  njanja

Nakon što učinio neki stvarni testiranja da biste vidjeli učinak na smanjenje težine u odnosu na KS. Našao sam da postoje znatne dobitke se izvršiti ako je težina je uklonjena iz šipke i klipova. U jednom trenutku prije nekoliko godina mi je napravio titanija štap za kovanje i poigravao se sa što povoljno skup titana Šipke za B i K motora. Nažalost, titan cijene više nego utrostručio tijekom 1 godine vremenski okvir i cijene mi morati naplatiti uzdigao do razine da su ljudi u toj industriji jednostavno ne bi mogla priuštiti.

Doing Dyno ispitivanja motora na b18c motor. Smanjenje težine 140 grama po cilindru na svaki štap con dala 5 dobitak KS vrha. Umu da je to pod istim opterećenjem i isti motor, jedina promjena je bila con štap težine. Čak i više nego značajan 5 vrha KS dobitak bio 13hp dobit na 800 rpms nakon vrha vlasti. Krivulja snage u osnovi stan podstavljene nakon što je dostigao najvišu vrijednost, gdje je kao teža čelične šipke bi taper off mnogo brže.

Kao okretaja povećava se nalazi i povećanje u iznosu od sile / KS morati promijeniti smjer klipa i štap. Teža klip i štap više sile koja je uzaludan promijeniti svoj smjer. Crank shaft također ima centrifugalne sile koja djeluje na njega. Ako težine može se smanjiti će biti manje sile potrebne za izmjenu njegovu brzinu ili stopa ubrzanja.

Za mene je stvarno čudno vidjeti ljude kupiti aftermarket štapove koji izvagati iste ili više od stock štapove. Nema koristi tako što ikad i ako štapom je teža onda ste stvarno labav nešto. Stock šipke su dosta jaki i sve dok to ne učinite glupe stvari kao što je iznad ili rev rev dalje od onoga što je potrebno, onda oni stvarno nemaju nikakvih problema. Agresivni marketing je trenirao ljude da vjeruju da im je potrebno zamijeniti neke dijelove koje zapravo ne nudi nikakvu korist.

Što se tiče materijala štap i titana šipke ići sam zaključila da razreda 6AL4V titanija isn't prikladna za priključak štapova. Postoje i druge ocjene koje su pogodne, ali trošak je više kao dobro. 6AL4V nedostaje čvrstoće, kako bi osigurao adekvatnu dugovječnost za dugotrajno korištenje. Za kratkoročno iskoristiti svoj prekid pravedan poput aluminija.

Ima načina da se 6Al4V adekvatan, ali to zahtijeva smanjenje težine klipova. to smanjuje količinu snage potrebno držati na to na visokim RPMs.

4.340 čelika može se toplina tretiran do 250.000 psi TS (vlačna čvrstoća) normalni 6Al4v je samo 110.000 psi TS. Iako 6al4v može biti toplinski tretiran na 160.000 psi TS to je rijetko. Postoje ocjene od čelika kao što je 300 koje se mogu toplinski tretiran na preko 300.000 psi TS. 300M troškovi 3. što titana troškova ali teži dvostruko više. Dakle ....... to je zaista samo oko 30% manje od titana kako bi nakon tih faktora ili uzeti u mjesto. Isto tako ovi materijali su jednako teško stroj i rezač život je uvelike smanjena.

Malo ljudi troše novac ili novac potrošiti na kupnju optimalan dio. na taj način završili su naseljavanje zbog onoga što si mogu priuštiti. To je dio razloga ne vidite ove "egzotične" dijelovi dostupni, ljudi jednostavno ne mogu ih priuštiti.

Ako ja motor za moje samo 9 puta od 10 mogu koristiti crower štap Maxi lite. Oni su oko 100 grama lakša od dionice štapove. Cijena je oko 700ish set. Imam ih za oko 10 godina i nikad nije bilo problema s njima. Oni težiti oko 400 grama ish. Cunningham također čini jako lijepo štap koji teži otprilike ista je cijena i slično.

Weight reduction, bez obzira gdje se primjenjuje ima brojne prednosti.

bolje plin miliage

Pa jebali te stapovi sto nisi popravio u klipnjace ...i ostale ....greske u prevodu kompjutera

nema potrebe, razumije se sve.

Ti neznas ili znas da ima mnogo gorih stapova na forumu od tebe a ti si STAP....

http://me.engin.umich.edu/autolab/Projects/Completed/InCylinderFrictionMeasurement.html (http://me.engin.umich.edu/autolab/Projects/Completed/InCylinderFrictionMeasurement.html)
http://www.autosteel.org/AM/Template.cfm?Section=Technical_Documents&CONTENTID=23463&TEMPLATE=/CM/ContentDisplay.cfm (http://www.autosteel.org/AM/Template.cfm?Section=Technical_Documents&CONTENTID=23463&TEMPLATE=/CM/ContentDisplay.cfm)
http://www.eng-tips.com/viewthread.cfm?qid=246316&page=5 (http://www.eng-tips.com/viewthread.cfm?qid=246316&page=5)