Dished Pistons

[DTRMiguel]

Ive looked around online and i cannot find an answer. Mabey someone on here can help me. What is the purpose of a dished pistons, 0cc,11cc,25cc? What does that mean i know different cc's will change the compression ratio but are certain pistons meant for specific applications,should i not go over/under a certain cc? Im lost :help:

[Blackened300a]

Usually dished pistons are for lower compression applications like turbo or supercharged engines. Domed pistons are for high compression.

[DTRMiguel]

So our motors are 10:1:1 correct? Is that considered low or high?

[DTRMiguel]

The reason i asked is because i was looking at a ModMax rotating assembly and was thinking of 17cc or 23cc. But didnt know the benefit?

[Joe Walsh]

Usually dished pistons are for lower compression applications like turbo or supercharged engines. Domed pistons are for high compression.

^^ +1 ^^

The amount of 'dish' in the piston that you use depends on a lot of factors that effect compression ratio:

amount of boost, if forced induction
cylinder head chamber volume
thickness of cylinder head gasket
compression height (length of rod and height of piston vs. deck height)
octane of gasoline used in the engine

Correct. 10:1 is fairly high in today's world of 93 octane fuel.
Most high boost applications run a reduced ratio of 8.5 or 9:1.
It really depends on how much boost you are going to run.
If you are staying N/A or not running a lot of boost, stick with a 10:1 compression ratio....it helps your low-end torque.

[RR|Suki]

Ive looked around online and i cannot find an answer. Mabey someone on here can help me. What is the purpose of a dished pistons, 0cc,11cc,25cc? What does that mean i know different cc's will change the compression ratio but are certain pistons meant for specific applications,should i not go over/under a certain cc? Im lost :help:

I'm assuming what you want to know is which cc gives the different compressions?
http://dagostinoracing.com/index.php?main_page=product_in fo&cPath=2678_123_1521_1528_15111&products_id=9680
that's an alright illustration of how it works, there are precise measurements that your engine builder will take to get you the proper dish instead of the ranges seen above (none of which I know).

[RR|Suki]

The reason i asked is because i was looking at a ModMax rotating assembly and was thinking of 17cc or 23cc. But didnt know the benefit?

I'll take it you mean -17 and -23? that seems like a lot, unless you are putting massive amounts of air through it

[DTRMiguel]

I'll take it you mean -17 and -23? that seems like a lot, unless you are putting massive amounts of air through it

Well the 9cc copmression ratio is 10:30:1
17cc is 9:19:1
and 23cc is 8:68:1

Which is best for a SC application?

9cc im guessing

[DTRMiguel]

When i SC ima go either turbo or Twin screw with high psi 18 at a min for the SC.

[bob6364]

Well the 9cc copmression ratio is 10:30:1
17cc is 9:19:1
and 23cc is 8:68:1

Which is best for a SC application?

9cc im guessing

The 17cc is the amount of water you could pour into the top of the piston..thus you are adding 17cc's of volume to your cylinders thus increasing their volume and lowering you over all compression a 23cc dished piston will add 23cc's of volume and so on...if i where going to run a roots supercharger i would shoot for just under 9:0 or a Centrifugal would be just over 9:0
But eveyone has there opinion....:D

[RR|Suki]

Well the 9cc copmression ratio is 10:30:1
17cc is 9:19:1
and 23cc is 8:68:1

Which is best for a SC application?

9cc im guessing

I can't remember what mine are off the top of my head, I'd have to dig up my sheet... so I'll likely never remember. My comp is something like 9.1 and are -11cc dish again on the sheet that I'll likely never see again, but I think that's the number... either way I digress, you don't need super low compression to run good amounts of power I'll never make the kind of power my motor can handle with a good tune... also some builders are are using higher comp with superchargers.
I wouldn't get too caught up with PSI, PSI is just a function of the restriction in your motor, I'd concentrate more on the whp numbers. I went from 14-15psi to 11 psi with the bigbore and lower compression to now 9 psi with big headers and big exhaust and some other tiny things all with the same pulley... hp went from 430 to 455 to now 510+ or so (based on mph change haven't gotten on the dyno again yet).

[Zack]

Stock MM dish is -3cc.

To achieve 10:1 with a 5.0 Stroker kit, you will need a -9cc piston.

I always have my engines built with 9.5:1 or higher.

[DTRMiguel]

OK so 9:1 or 9:5 are both cool?

[RR|Suki]

OK so 9:1 or 9:5 are both cool?

talk to your builder, tell him exactly what you want to do and go from there