Anyone running 8.5 compression with 2.2L

[The S is Silent]

Quote:

Originally Posted by Una Yeah, I do that on every N/A engine I get near. Swirl head and MPFI does wonders for waking up the good old HO engines.. hahah..

WERD! That's the plan with my old HO!

[johnl]

Quote:

Originally Posted by The S is Silent Doesn't a 2.2 with G-head pistons and a 782 head have compression around 8.5? Maybe even a couple of tenths more?

In looking at the posts at "induction - 782 chamber," I learn from "4 L-bodies" that the chamber volume of the swirl is 49-50 cc and the G is 55-56cc, and that the piston dish volume for '85 G pistons is 9cc while for the 86+ swirl pistons is 24cc.

So, 85 G head w/ 85 pistons is 55 + 9 = 64cc and 550cc/64 = 8.59CR stock.
And, 85 G head w/ 86+ swirls is 55 +15 = 70cc and 550cc/70 = 7.86:1 CR for the G head/swirl piston combination.

8.59 - 7.86 = .73 decrease in CR

[Chucksrt]

I always thought that the stock compression was around 8:1 tops? I think 8.5:1 is the best all around compression for a turbo car. Decent responce and still leaves enough room to squeeze (boost)air for max performance

[SwiftTech]

mopar performance sells 8.5:1 cast pistons, i bought a set about a year ago but sold them shortly after getting them.

[glhsken]

Quote:

Originally Posted by johnl In looking at the posts at "induction - 782 chamber," I learn from "4 L-bodies" that the chamber volume of the swirl is 49-50 cc and the G is 55-56cc, and that the piston dish volume for '85 G pistons is 9cc while for the 86+ swirl pistons is 24cc. So, 85 G head w/ 85 pistons is 55 + 9 = 64cc and 550cc/64 = 8.59CR stock. And, 85 G head w/ 86+ swirls is 55 +15 = 70cc and 550cc/70 = 7.86:1 CR for the G head/swirl piston combination. 8.59 - 7.86 = .73 decrease in CR

The decrease will be correct, but you have to add in the HG "volume" to get the real compression #

[glhsken]

Quote:

Originally Posted by Chucksrt I always thought that the stock compression was around 8:1 tops? I think 8.5:1 is the best all around compression for a turbo car. Decent responce and still leaves enough room to squeeze (boost)air for max performance

I agree, That's what I try to run all the time.