anyone want to fill me in?

[jjfizzle51]

hey guys i did a little search and didnt come up with anything can you guys just tell me what a longer crank saft does. from what ive read you need shorter pistons so im gussing it makes the pistons go up and down quicker. can some one correct me if im wrong cause that was just a guess

 

thanks for any help

[chase@miamiatv.com]

overall i no not mthat much about them , just a little bit im sure a pro here will fill u in scientifically

 

however to accomodate the stroke you must have a spacer plate taht goes between the cylnders and the base gasket on stock jugs, to accomodate the stroke of the pistons travvling FURTHER , if not they would push thru the top of the engine.....

[jjfizzle51]

so your is the whole point to move the piston further up and how would this benifiet

 

sorry but im new to the engine internals

 

but thanks for any more help

[chase@miamiatv.com]

im really not the guy to ask for this ..... it moves the piston in a longer matter getting a bigger stroke and increasing the power . I THINK the increase of stroke like a 4mm has a bigger rotating mass and most 4mm's fit in a case without trenching the case out ......... I figure its more rotating mass because a 10 mill requires serious case trenching to accomodate a larger rotating mass .... someone has gotta know the real info about this im not really the guy nor i want you to take any of my " knowlege " around cuz im sure someware along the lines im wront ...... thats just my 2 cents

[dawarriorman]

You can either stroke the crank and gain displacement, or run a longer rod, which keeps your displacement the same (you can do both too). Adding stroke is accomplished by moving the pin on the crankshaft out further. The longer rod gives it less of an angle, which should make it more reliable. For either one you have to do something to account for the fact the piston is further up in the cylinder, although Im not sure what all you do with what setups. I know they use blaster pistons, as they have a smaller pin to crown length than a banshee piston, and they use spacer plates for some setups too.

Edited January 22, 2006 by dawarriorman

[chase@miamiatv.com]

u need any warrior parts i almost got everything left ( stock )

[itsaripper]

You have four choises

 

1 Stock crank : stock type pistons, OME or Wiseco

 

2 Stock crank, long rod : Use wiseco 795 series pistons. The pin is moved up to

offset the extra length of the rod

 

3 Stroker crank , stock rod: Use stock type pistons again here

 

4 Stroker crank. long rod: Use Wiseco 795 series pistons. This is where you use

the spacer to take up the extra space the stroker

crank gives you. You can also have the head cut to

take up this space, and have port work done to raise

them to keep the timeing right.

 

The long rod will give you more torque, which is really what moves you, and that is good. What is happening is the piston stays at TDC longer to let the gas burn better. At BDC it let more fuel charge in cause it stayes longer befor it moves up to close the ports. It has a better angle on the crank.

 

If I have got something wrong here I'm sure it will be pointed out momentarly

[2003LimitedBanshee]

You have four choises

2 Stock crank, long rod :

Edited January 22, 2006 by 2003LimitedBanshee

[Animalman294]

Now thats what I like about this site is not only is the information accurate, and if its not it is quickly corrected by others, but when it is most of the time the members are cool when correcting others. Between the two of you you pretty much hit the right answer.........right on

[itsaripper]

03limitedban You are right about the long rod. I stand corrected. But on a stroker it works just like I said. Let me give you a example. Take a two inch circle and a fifteen inch circle. They both have 360 degrees. If you move something from 10o'clock to 2o'clock on the two inch circle, it goes pretty fast. Now do the same on a fifteen inch circle and it take a lot longer. The piston hangs around the top longer and the bottom longer.

 

My understanding of the 795 series pistons is they are used on a long rod only. The long rod being the RZ 400 rod used in the banshee 350. The stroker has to be delt with by some other means. Useing a plate or moving up the ports, and cutting the head for the piston to come up the extra.

A longrod stroker can use the 795 piston but it is only taking care of the long rod. The stroker takes something else to compensate for its added length.

 

Now if I am wrong here again at least everone can benifit from my stupidity of putting it out here for ya to read.

[PassionRE]

hey guys i did a little search and didnt come up with anything can you guys just tell me what a longer crank saft does. from what ive read you need shorter pistons so im gussing it makes the pistons go up and down quicker. can some one correct me if im wrong cause that was just a guess

 

thanks for any help

462779[/snapback]

 

 

 

Mind boggling isn't it? Heres what's really happening. First of all, stroking a engine is simply increasing it's ability to draw in more fuel air mixture by increasing its displacement. A engine is really just a pump in its simplest form. Increased stroke just allows it to draw more in, like a syringe that's just a little longer than normal. As you pull the syringe, if it has more travel than normal, its going to pull in a little more fluid. Thus ,more fuel air mixture that's been drawn in, compressed at a given rate(compression ratio), will produce a more powerful explosion which is transmitted to the crank, trans., and ultimately, the rear wheels. In the case of a 4 mil vs. Stock stroke Banshee, this rate of increase is minimal in reference to the displacement increase itself. . The real power is increased in what it does to the port timings. Take a stock Banshee, throw in a 4 mil. crank and alter the transfers and exhausts just to compensate for how much further down the piston travels in the cylinder(2mm). Im not talking a full tilt port job, just enough to allow for full port opening at BDC. Your exhaust duration has now gone from 181.04 deg. To 182.35 deg., not much their going on is there. But now the transfers have gone from 119.69 deg. duration to 126.18 deg. Whoa...there's a difference. Its pretty apparent that stroking the motor has a lot more effect near BDC than it does near TDC. With this big increase in transfer duration we have increased the efficiency range of our transfer ports. They will now cause the engine to not only hit harder down low, they will be more efficient at higher RPM as well. This is just a port timing match up situation, not a port job, modify the ports even more, especially the exhausts, and we have the recipe for real HP.

As for long rod vs. Standard rod, the long rods simply reduce the rod angle during operation which will reduce wear on our piston and bore surfaces. A 4 mil increase in stroke on a Banshee isn't really enough to justify this, but hey , reliability is a good thing, we'll take it with a smile. The long rod does have a slight effect on port timings too, and it does also cause the piston to stay at TDC while waiting for the crank to start moving the piston back downwards to the tune of an additional .64 degrees. It also decreases the transfer duration at the same rate at BDC. So, in essence the longer rod removes .64 degrees over-lap at BDC and adds it toTDC.......Jim

[jjfizzle51]

Mind boggling isn't it? Heres what's really happening. First of  all, stroking a engine is simply increasing it's ability to draw in more fuel air mixture by increasing its displacement. A engine is really just a pump in its simplest form. Increased stroke just allows it to draw more in, like a syringe that's just a little longer than normal. As you pull the syringe, if it has more travel than normal, its going to pull in a little more fluid. Thus ,more fuel air mixture that's been drawn in, compressed at a given rate(compression ratio), will produce a more powerful explosion which is transmitted to the crank, trans., and ultimately, the rear wheels. In the case of a 4 mil vs. Stock stroke Banshee, this rate of increase is minimal in reference to the displacement increase itself. . The real power is increased in what it does to the port timings. Take a stock Banshee, throw in a 4 mil. crank and alter the transfers and exhausts just to compensate for how much further down the piston travels in the cylinder(2mm). Im not talking a full tilt port job, just enough to allow for full port opening at BDC. Your exhaust duration has now gone from 181.04 deg. To 182.35 deg., not much their going on is there. But now the transfers have gone from 119.69 deg. duration to 126.18 deg. Whoa...there's a difference. Its pretty apparent that stroking the motor has a lot more effect near BDC than it does near TDC. With this big increase in transfer duration we have increased the efficiency range of our transfer ports. They will now cause the engine to not only hit harder down low, they will be more efficient at higher RPM as well. This is just a port timing match up situation, not a port job, modify the ports even more, especially the exhausts, and we have the recipe for real HP.

As for long rod vs. Standard rod, the long rods simply reduce the rod angle during operation which will reduce wear on our piston and bore surfaces. A 4 mil increase in stroke on a Banshee isn't really enough to justify this, but hey , reliability is a good thing, we'll take it with a smile. The long rod does have a slight effect on port timings too, and it does also cause the piston to stay at TDC while waiting for the crank to start moving the piston back downwards to the tune of an additional .64 degrees. It also decreases the transfer duration at the same rate at BDC. So, in essence the longer rod removes .64 degrees over-lap at BDC and adds it toTDC.......Jim

463038[/snapback]

my brain hurts now after reading that

 

j/k thanks for all the help you guys i understand the whole concept alot better