BigTex

iTrader: (16)

Here is my guess:

04BlackSilverado

iTrader: (6)

Yeah but aren't the heads of LQ9's Aluminum, and the LQ4's Iron?

BigTex

iTrader: (16)

I think I need the BV. Pass the bottle my way.

Now, where is that stick ->

zippy

2001 and later LQ4's come with aluminum heads. it's like when people use the term LS6 intake. it annoys the hell out of me since it's not in any way shape or form LS6 specific. in fact it has come on more LS1's than LS6's. same kind of issue.

now where's that horse.

Ryan23silverado

iTrader: (1)

Not to hijack, but what would be the compression ratio of an LQ4 with 64cc combustion chambers? Does anyone know the dish cc in the pistons of the LQ4 engine?

Ryan23silverado

iTrader: (1)

"I calculated out the dish to be about 8cc on the LQ4. Thats the only difference."
Ah, the search button

How about the compression ratio of that LQ4 running cylinder heads with a 64cc combustion chamber and a stock MLS gasket?

BigTex

iTrader: (16)

Sounds familiar.


Pretty darn close to 10:1. But, a better alternative is to run the Felpro 1041 head gasket. Its got a .043 compressed thickness instead of stock .060. This will not only further increase the CR but will move the quench area into a much better number for controlling detonation.

I think I posted this before, but here is a shot of a LQ9 piston and rod beside a LQ4 piston and rod. LQ9 is definitely the stronger of the two (on left).

spearfish3

Do you know if either of those rods are powder metal rods. It looks like the LQ9 is powder metal which is less weight but more brittle that the smaller forged (looks that way) LQ4 rod. Personally I would rather have the forged because it will take a little detonation and not explode. 01 and up ferd powerstrokes have to be careful of propane because it has grenaded its fair share of rods through the sides of the engines. If you are building a high HP engine watch out for the powder metal rods because they don't like anything out of the ordinary.

BigTex

iTrader: (16)

They are both forged powdered metal connecting rods.

spearfish3

My bad, well then the LQ9 is a lot better.