How to calculate compression Ratio?

[EG9]

Guy, I need your help on this.


May I know anyone know how to calculate CR for this setup: 7AGE 16V.

Engine Head from: 4AGE 16V Small port

Engine Block: 7AFE

Piston from 4AGE 20V (AE111)-Blacktop.


0.5mm metal head gasket will be used on this setup, may I know what is the compression ratio for this setup. Thanks!

 

[shamburke]

wie.. chu.. you wnat it for WISH ka????

 

[TRDae92]

Chu, i find few web might help u up

Engine Compression Ratio (CR) Calculatorhttp://www.majorleagueduning.com/tech/Scripts/compressioratio.htm

http://users.specdata.com/home/emxjc/compression_ratio.html

 

[chinozie]

then this one should be one of our topic during TTT...heeeeee

 

[hitz]

It must be for chu newly sideway monster machine wan... hehehe..

 

[EG9]

Thanks for the feedback guy.

yes, it's for WISH!!!

hahahahah

 

[EG9]

Some of the guys from Club4ag.com feedback that this setup will be 14:1 CR. Which is very high. Headeach on this.

 

[GT20v]

thicker head gasket?
use 16v small port piston??

that shud drop it around 12:1??
well i dunno....just guess hehehee

 

[QiW]

just put in that comp test meter laa ... then compare it with another engine which the CR u already know .. this method of coz not 100% accurate la .. but close enuff liauu ... :p

 

[20vturbo]

14.1 cr?

i wonder wont it causes knocking bro? should be running on higher ron rite?

 

[EG9]

I don't think it's 14:1 compression ratio.
Although I have the formula to calculate the CR, but I don't have some value needed to add in for those calculation.

Normal 7AGE 16V setup that I read from other country forum is using 4AGE 16V head and piston only have 9:1 CR. (and they are using 0.5mm metal head gasket as well)

The only different stuff in my setup is blacktop 20V piston. Will it jump up to 14:1 CR? I doubt it.

 

[EG9]

just put in that comp test meter laa ... then compare it with another engine which the CR u already know .. this method of coz not 100% accurate la .. but close enuff liauu ... :p

who have comp test meter?

can borrow? hehe

 

[cuscostrutbrace]

Compression ratio is best calculated when the engine is disassembled.Roughly,calculate the swept volume+deck+chamber volume and divide by chamber volume.I think 7AG should be around 10 CR since the G type chamber volume slightly larger than F type chamber.Compression meter cannot use to measure CR,not accurate.

my 2 cents

 

[netmatrix]

Compression meter is used to measure compression loss.

 

[chinozie]

then...
use the comp test meter...
crank for...let say 3-4 times...
n then get the average reading ler...
unless if chu's engine already on the floor...

 

[EG9]

Compression ratio is best calculated when the engine is disassembled.Roughly,calculate the swept volume+deck+chamber volume and divide by chamber volume.I think 7AG should be around 10 CR since the G type chamber volume slightly larger than F type chamber.Compression meter cannot use to measure CR,not accurate.

my 2 cents

When u came back?

So my setup should not be more then 12.5:1 CR?

7AFE block, Blacktop piston, 4AGE 16V small port, blacktop piston.

 

[cuscostrutbrace]

CHu,just come back about a week,after that straight go to work,then weekend busy with sic drag,sorry didnt call u,already here now,might need your help also..

Blacktop piston,hmm..i dont think will be more than 12.5 also,maybe 11.5-12

 

[sincere1]