Help, need info about piston spec.AUDSPEED - beware

[s4power]

I ordered from AUDSPEED.COM Wiseco pistons.In my opinion they are around 9.1 cr.I was trying to contact him, but without success.Hi just talking that he don't know nothing about them and they are for sure 8.5 cr, but in my opinion they are higher.
Beware AUDSPEED is liar.Don't thrust them!He won't answering on mails, no communication, poor technical knowledge.

Here are the pistons spec:

http://i37.tinypic.com/2cxggn5.jpg

http://i38.tinypic.com/2u7m4p1.jpg

Could somebody find these informations and help me calculated compression ratio.

My engine (3b) has forged 144mm H-beam rods, with OEM rs2 headgasket.How high cr could I expecting with these pistons.

We need to find these data

bore : 3.1890
stroke :?
Piston Volume - (CC's, Negative for Dome)?
Combustion Chamber Volume - (CC's)?
Compressed Gasket Thickness (rs2) - (Inches)?
Piston to Deck Clearance - (Inches)?

http://www.doverusa.com/compression-ratio-calculator.htm

Thanks for your help

[Jamo]

Why do you think they are no 8.5? They are decked flat unlike standard pistons so on lvisuals alone I would suggest they are lower than stock pistons.

Can you refrain from posting things about lying unless you can back it up with fact please.

[s4power]

My friend ordered real 8.5 cr wiseco pistons directly from Wiseco and they are totaly different construction, not flat on the top etc...I would like to calculate from data real CR.Do you know how?

[Jamo]

Well it depends if they custom made the pistons or used of the shelf.

All the information is on the forum in many different threads, there are also spreadsheets on the forum where you simply enter your data

[Jamo]

BTW these are JE flat top pistons at 8.5 cr

http://www.80tq.com/gallery/JEPistons

[s4power]

Does somebody know that by heart?I was trying to find these spec but without success.

[Jamo]

Try these

[s4power]

Hm...are you sure.Maybe they are made by JE spec, but for sure, they are Wiseco.

Do you think they are still 8.5cr?In my opintion cr is higher

Here is picture at TDC

[Jamo]

Yes because AFAIK standard pistons protrude into the squish area at TDC and those decked ones don't go into the squish area.

I have not seen with my own eyes standard pistons at TDC however.

[s4power]

Maybe you are right, but would be fine if somebody who knows, how to calculate cr from this data confirm your theory.

Still waiting for some technical expert to calculate these data.

[s4power]

bump

[AndyP]

I'd agree they are higher than 8.5:1. All the dimensions are the same as a std piston which will give around 9.0:1, except yours don't have the 2cc dish on the crown like std. If you add another 2cc to your volume at TDC it gives you 9.3:1.
All these figures came from the spreadsheet that Jamo posted earlier.

[mcandmar]

They do have a lot of material removed around the valve pockets, and a large recess where standard pistons have a raised squish area.

[Jamo]

Yep they look 8.5 to me from other flat decked pistons I've seen, contact Wiseco directly would be my advice.

From the order number they can tell you.