Riddle me this. what is my comp on a 4.6

[boostingbuick]

Ok, here's what I got. A 03 Cobra short block with stock crank and rods. A set of 01 Lighting pistons, which have more of a dish and SOHC heads. Any guess what the compression ratio maybe? I believe the SOHC heads have a smaller combustion chamber and was hoping that the bigger dish piston will keep the compression ratio around 8 to 1 or a bit higher. I will get around to have everything cc sooner or later but until?

 

[soap]

Something custom like that I don't think you should be guessing at it. Stock is 8.5:1, so it will certainly be lower than that.

--Joe

 

[wikdsvt]

Something custom like that I don't think you should be guessing at it. Stock is 8.5:1, so it will certainly be lower than that.

--Joe

why would you want compression that low? Many Lightning Guys up it to 9.0 or 9.1 to 1 and run more boost.

 

[boostingbuick]

Turbo. What is the stock compression of a lighting?

 

[CobraSVT657]

It should be 8.4 compression stock

 

[boostingbuick]

I found with a 23cc piston and PI heads will yeld 8.5 to one. Now I need to find what cc the Lighting piston is.

 

[2L8IWIN]

what cc are the lightning heads?

on a 5.4 a 21cc dish piston will yield 8.5:1 on a 42cc combustion chamber, 8.2 on 45cc, and 7.8 ona 52cc, respectively...