piston chatter

[banshee(911)]

I agree with fire guy on this one. I would get s second opinion on the clearances. We have also noted more piston slap with the the short skirt pistons that Vitos sells. The shorter skirt does several good things but at the sacrifice of piston stability and durability. You need to pay special attention to the cylinder taper and out of round specs. If everything is good, ride it. I will say that some strokers just make a little more noise.

Brandon

hmm....now im thinking getting new pistons and rehoning it anny suggestions on pistons and i do have an agressive trailport but no boost ports think i should have him put some in?????????

[RZBansheeMan]

I hope you don't take offense to this, but when going to the stroker crank, it would have been a better idea to use the longer rod set up. The reason being is longer stroke and stock rod will net a lower rod to stroke ratio and increase rod angularity. This will put more load on the piston skirts front and back which is not good. You definately don't want any piston chatter in any engine.

[banshee(911)]

I hope you don't take offense to this, but when going to the stroker crank, it would have been a better idea to use the longer rod set up. The reason being is longer stroke and stock rod will net a lower rod to stroke ratio and increase rod angularity. This will put more load on the piston skirts front and back which is not good. You definately don't want any piston chatter in any engine.

no i dont take any affense to it but kinda new to a stroker motor actually its my first one but from now on i will b going with the long rod but spent all this money now im gonna use it

[96_banshee_96]

Go with Wiseco pistons... They are the shit :thumbsup:

[banshee(911)]

Go with Wiseco pistons... They are the shit :thumbsup:

im @80 over wich is 66mm think i should go with blaster pistons kuz im not running them now but have heard allot about them?

[RZBansheeMan]

Blaster pistons were a thing of the past.......

They were used with a stock stroke crank and yamaha RD 400 rods which were 5mm longer.

This was the old 370 long rod motor. Your best bet is to have the cylinders mic'd and if needed, get bigger pistons and have the jugs bored to them. Go with the wiseco pistons and and have the clearence set at the recommended size. If I'm not mistaken it should be .003"

[banshee(911)]

Blaster pistons were a thing of the past.......

They were used with a stock stroke crank and yamaha RD 400 rods which were 5mm longer.

This was the old 370 long rod motor. Your best bet is to have the cylinders mic'd and if needed, get bigger pistons and have the jugs bored to them. Go with the wiseco pistons and and have the clearence set at the recommended size. If I'm not mistaken it should be .003"

whats the max bore i can go im already @66mm

[RZBansheeMan]

I'm not sure what your best option is but wiseco's website shows 66.5 mm for stock stroke and stock crank.

They show 66 mm for long rod stock stroke and 66mm for the 4mm long rod. As for the blaster pistons they start at 66 mm and go up to 68.25 mm, but you would need a stock stroke long rod set up.

[FireHead]

I agree with fire guy on this one. I would get s second opinion on the clearances. We have also noted more piston slap with the the short skirt pistons that Vitos sells. The shorter skirt does several good things but at the sacrifice of piston stability and durability. You need to pay special attention to the cylinder taper and out of round specs. If everything is good, ride it. I will say that some strokers just make a little more noise.

Brandon

Once you start getting into short skirts you start asking for trouble when it comes to durability and reliability. <insert joke here>

It is advantageous in a high rpm engine to have as little mass and friction as posible away from the crankshaft centerline. However, this also means your piston loses it's ability to guid itself among a myriad of other problems. I'll stop here before I go off on a rant about pistons that have nothing to do with Banshees.

 

With regard to cylinder machining, I would agree with Brandon in that you need to pay special attention to your cylinder measurements. In general, I would say that Jim-Bob at your local machine shop (that calls a drill press a mill) can usually make a satisfactorily round hole, but they are usually tapered, off center, and wildly variant when it comes to bore diameter. Generations of imbreeding has also programmed the machine shop / mechanics to lie about all of this.

[joneser4u]

Mine has chattered ever since I put the longrod stroker in,I also had a jug resleeved at the same time,I questioned the bore being straight in the new sleeve,it was bored to match other jug. That was 4yrs ago.I have honed and replaced the pistons/rings 3 times with Weisco prolites.It sounds terrable but it runs like a champ?

[BigRed350x]

Once you start getting into short skirts you start asking for trouble when it comes to durability and reliability. <insert joke here>

It is advantageous in a high rpm engine to have as little mass and friction as posible away from the crankshaft centerline. However, this also means your piston loses it's ability to guid itself among a myriad of other problems. I'll stop here before I go off on a rant about pistons that have nothing to do with Banshees.

 

With regard to cylinder machining, I would agree with Brandon in that you need to pay special attention to your cylinder measurements. In general, I would say that Jim-Bob at your local machine shop (that calls a drill press a mill) can usually make a satisfactorily round hole, but they are usually tapered, off center, and wildly variant when it comes to bore diameter. Generations of imbreeding has also programmed the machine shop / mechanics to lie about all of this.

 

Not uh! Every hole a machinist makes is absolutely and perfectly straight and maintains the same diameter bore throughout the entirety of whatever thickness material said hole is going through.

[Snopczynski]

Blaster pistons were a thing of the past.......

They were used with a stock stroke crank and yamaha RD 400 rods which were 5mm longer.

This was the old 370 long rod motor. Your best bet is to have the cylinders mic'd and if needed, get bigger pistons and have the jugs bored to them. Go with the wiseco pistons and and have the clearence set at the recommended size. If I'm not mistaken it should be .003"

 

We have a couple 4 mills with long rod hot rod cranks and blaster pistons in them. They work well, just cut the extra tolerance in the cool head domes.

 

I would probably check compression and see what it is.

[FireHead]

Not uh! Every hole a machinist makes is absolutely and perfectly straight and maintains the same diameter bore throughout the entirety of whatever thickness material said hole is going through.

You would not believe (maybe you would) what passes for an engine shop in local competition NASCAR country in the South. It's a dude with no teeth and a worn out morse taper drill press with a worn out boring head that was cheap even when it was new 60 years ago. Oh yeah,o and the drill press is usually sitting on a dirt floor out, in a shanty outside the speed shop. :ermm:

[RZBansheeMan]

We have a couple 4 mills with long rod hot rod cranks and blaster pistons in them. They work well, just cut the extra tolerance in the cool head domes.

 

I would probably check compression and see what it is.

 

Thanks for the info, this is something that I was unaware of. How would that work with his 4mm crank and short rod though ?

[banshee(911)]

well i guess im gonna get another set of pistons and c if they do the same thing seeing how tha machinisttold me the piston was not the same it lost a thousand and 1/2 but in order to do that i will have to give up my super stockers and the extra 6 hp i will have to get some boost ports to make up diff.well thanx guys been verry helpful next time to rebuild i will b going to the cubs think theres much of a diff in horse power or torque?