Wiseco 4.1 forged Pistons

[buddy]

I picked up a set of wiseco Pistons form another website for the 291 4.1 I'm building. They were sitting In a guys attic forever never opened. It turns out my bores are 4.0005 so I'm not sure I'm going to be able to use these since there for 3.995 bore. I'm not sure if they are custom or not, but I'm curious if there is any market for them so I can get the money back to buy some proper forged Pistons for my setup

 

[buddy]

The only variable is that I only used a digital caliper measuring the bores. I haven't brought the block to machine shop to be looked over and checked. If the shop gives me the ok to use them, I will but I think he's going to say they are too small.

 

[buddy]

 

[PSID6]

IMO until you stick a bore gauge in there I wouldn't get rid of them. There are coatings out there that can add .005-6

 

[fastblackracing]

I would be concerned about the thickness of the top of the piston if these were not
intended for turbo duty when they were made the top may be thin.
I usually aim for .250 minimum crown thickness for something that is going to
see some horsepower.
Would also be nice to see how far down that top ring land is.....
Wiseco usually reccomends .0045 piston to wall clearance and you are only a touch over....see what the shop measures it at.

 

[buddy]

Great replies guys thanks. These were supposedly for a turbo build but we'll see if the shop can use them. How much do you guys think these cost and so you think they're fully custom.

 

[ek02]

Measure the pistons, because if they are for a 3.995 bore, chances are they are 3.990 diameter. Rings are hard to find for that bore if the grooves are 1/16". If they are 5/64", then no problem.

 

[Undercover87T]

They would fit a .030 over 4.1, yours is now .040 over.

 

[buddy]

Are custom Rings extremely expensive?

 

[ek02]

A one off set of rings for that bore would be very expensive if you could even find someone to make them. I made the mistake of ordering a set of custom 4.1 stroker pistons from JE for a 3.995 bore. The JE rep said 4" file fit rings would work. I file fit them and they always had blow by. I reused those pistons recently in another block and found a set of one off Diamond low tension file fit rings for a 3.995 bore from Terry Rosebush Motor Sports on E bay. The top ring is moly, the second a napier J hook. I used regular expanders from another ring set on the oil rings on advice from Diamond tech support. They are working perfect. It looks like he only has one set left if your ring grooves are 1/16". http://www.ebay.com/itm/Diamond-Pis...ash=item2a3020c854:g:MjoAAMXQwwlSCoaZ&vxp=mtr

 

[ben mccarty]

Did you end up using these in your build? If not, I am interested in buying them. I have a stock bore 4.1 that needs boring just enough to clean up and these would fit perfect. If you still need to get rid of them let me know and what you want for them.

 

[earlbrown]

Ben, you realize those slugs are .030" over... If all you need is a slight hone they won't work.

 

[buddy]

The Pistons are sold.