Engine: Excessive Deck Height

[CarCrosswordDan]

Were any Studebaker V/8's, other than the 259, engineered with an excessive amount of clearance between the top of the piston ( at top dead center ) and the top of the block deck ? Thanks, Dan

[Mike Van Veghten]

Been talked about.
All Stude V-8's had excessive deck heights.

Custom pistons will fix it.
Custom rods will fix it.
Block decking will fix it.

Do a search on the subject, lotsa reading.

Mike

[Chicken Hawk]

Were any Studebaker V/8's, other than the 259, engineered with an excessive amount of clearance between the top of the piston ( at top dead center ) and the top of the block deck ? Thanks, Dan

Factory specs for the 259 is .082"

Ted

[CarCrosswordDan]

Gee, I really don't understand that kind of engineering concept. Incredible. Dan

[irish]

I don't know why this is considered excessive. Many years ago when I was studying to be an aircraft mechanic I remember being told that a deck height of .050" or greater was the preferred deck height on a gasoline engine.

[sweetolbob]

This is more question than answer.

Aren't we also discussing Quench here. I realize deck height is not quench but if I recall correctly (deck height + gasket thickness = Quench) to put it simply.

That presented, I've generally been led to believe that in SBC's and other performance engines that about 0.040 quench gives a reasonable amount of turbulence to the fuel mix and above 0.050-0.060 is considered the upper limit for performance engines. For older lower compression engines the Quench was considered to be of less importance as overall performance is less affected.

As I said, this is more question than answer but I'd like to see what the forum folks think as reference.

Bob

[Jim B PEI]

Okay, refresh my memory. Would then a standard 289 be less than the 259's .082"? (I suppose it would be, but I can't place my hands on the info. Silly old brain) What was the 289 factory spec?

[Chicken Hawk]

Okay, refresh my memory. Would then a standard 289 be less than the 259's .082"? (I suppose it would be, but I can't place my hands on the info. Silly old brain) What was the 289 factory spec?

So they can use the same heads on the 259 and 289 and end up with the same compression ratio is my guess. The 289 deck is .031"

Bob, I think you are correct in that lower compression engines are not so critical to deck for performance. For what it's worth, the little 232 engine deck is .109" and being only 7.0 compression that little motor runs awfully good as small as it is as does the 259.

Ted

[shifter4]

Don't forget the difference in the pistons, as in Dished 289's and flat top 259.
All of this with the deck height results in the CR reamaining the same for the 2 different engine sizes , while
using the same head/combustion chamber ?