Wiseco recommends .0025 but after searching and reading what other people are doing like .004 - .008 PW clearances, will I be okay with .0025? or should I go with .0035? My motor is a b18b stock bore and is going to be NA. am planning to do 180- 190hp. Let me know what you guys think about my clearances because I really dont want to rebuild my motor again. thanks..

 

I would stick with wiseco's specs for your build.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">I would stick with wiseco's specs for your build.</TD></TR></TABLE>

X2 agreed.

People running larger than recommended especially in the 4 to 5 thou range are turbo cars.

 

okay thanks, so I should do .0025 would it hurt to go a little more like around .003?

 

basically, run what they recommend, though. no it won't hurt to be a little big(~.003 should be fine) its better to be a little on the big side rather than on the small side and not have enough oil clearance.

gl

-Chris

 

Do you guys think a good hone will get enough PW clearance? Or do I have to send my block offisland to a machine shop to get it honed and or bored to get the desired PW clearance since my pistons is for a std. bore 81mm

 

if your pistons are standard 81mm size, you really don't have much room to play with in your bores. if you don't have access to a dial bore gage, take the block to a shop that does and have them measure your bores to see where you're at. hopefully, your bores aren't tapered or out-of-round out of spec and you can just get them to hone it out to your desired PW clearances or at least deglaze the cyl. walls for you if you're really close to being "too big".

hope this helps.

-Chris

 

0.003 clearance is inches or mm?...

coul i use this clearance with turbo/?,..
i'll use Wiseco K567M84 with Darton Sleeves in B16

 

have a machine shop set the proper piston to wall. you cannot do it by guessing

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Shoei7 &raquo;</TD></TR><TR><TD CLASS="quote">0.003 clearance is inches or mm?... </TD></TR></TABLE>

Considering .003mm would be .00011" Im pretty sure its .003"

To the OP, why on earth would you think you are smarter than the manufacturer of the pistons?

 

I have a bore gage to measure the cyl. walls but I live on kauai so I would have to pay $500 just to ship it out to get it bored and honed to my wiseco pistons. Thats why I was asking if it would be okay to just hone the cyl. walls to get .0025'' or .003'' if my cyl. are all good and not out of round or anything. I know honing for a very long time will make the cyl. out of round but I shouldent have to hone it that much since its all going to be std. bore and all. Whats an OP? is it me? because alot of people say to go a little bigger on the PW clearance but most of them where for turbo motors. thanks for your help everyone.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Combustion Contraption &raquo;</TD></TR><TR><TD CLASS="quote">

Considering .003mm would be .00011" Im pretty sure its .003"

To the OP, why on earth would you think you are smarter than the manufacturer of the pistons?</TD></TR></TABLE>

lol, ever seen what happens to a turbo motor when you run the pistons at 0.002-0.0025 pw?

i run turbo motors at 0.0045, smaller bore NA stuff 0.0035.

build it loose only you know about it, build it tight and everyone will find out about it!

 

build it loose only you know about it, build it tight and everyone will find out about it!
What dose that mean? if I make it too tight then the pistons will expand too much and blow my motor. or if its built lose then the pistons will expand but theres room for it? but dosent piston rock crack the skirts if you run them too lose?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg &raquo;</TD></TR><TR><TD CLASS="quote">lol, ever seen what happens to a turbo motor when you run the pistons at 0.002-0.0025 pw?

i run turbo motors at 0.0045, smaller bore NA stuff 0.0035.

build it loose only you know about it, build it tight and everyone will find out about it!</TD></TR></TABLE>

Yes Ive seen. But this is not a turbo engine, we are in the NA forum. NA is OK @ .0025 but also OK at .0035.

The build is tight quote means that if you build it tight, everyone will know because it will blow.

 

the orange paper that came with your pistons says 0.0030-0.0040 if i remember correctly stay in that range you dont want a slug to over expand from leaning out and kill the cylinder wall.

 

Looser is better. Just do 0.100 clearance FTW.

 

lol !!! no friction FTW!

 

The screen-printed coating on Wiseco pistons accounts for .0007", so if you fit the pistons to .0025", the clearance in the real world is the same as .0032". The screen-printed Wiseco's have a "W" in the coating on the skirts. This coating isn't the same material as their old dry-film break-in coating.
I've run these screen-printed pistons as tight as .0020" at 89mm bore without any issues, so I do not recommend that you exceed Wiseco's recommended clearances by more than .0002-3" at most.

 

I was woundering if the coatings would mater and i guess it dose. Did you measure it yourself? I didnt see any papers that said that. Well I guess im going with what they reccomend me. Thanks alot everyone. Oh yeah, where would I find the studs that hold the intake manifold to the head? Thanks.

 

being endyn i think they measured everything ud think of from the piston..

knowing they sell their spec pistons being the Rollerwaves, and theyre made by Wiseco lol

they should know wiseco a little ehehe

 

The screen-printed coating is the same material used by Honda on their TSX pistons, of which we've had considerable experience. Aside from it's low-friction qualities, this coating also helps with piston noise. The most clearance we've run with the coating on a forged piston is .0034". This was in a high-heat application, and after reading the cylinder walls and piston skirts after 6-hours of dyno testing and 300 miles of racing, we've backed down to .003".

 

great info,thanks