ok first I want to know what the formula to get the deck height is and what parts will actually change the mm/inch of the height. This is measured from the wrist pin to the top of the piston correct? Or is it measured from the top of the piston to the top of the head?

One last thing as far as compression if you change deck height by increasing or decreasing rod stroke will it affect compression?

I already search but didn't find the formula for finding what deck height is

 

Deck height is center main to the top of the deck......

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Brent L &raquo;</TD></TR><TR><TD CLASS="quote">Deck height is center main to the top of the deck......</TD></TR></TABLE>

so from the wrist pin then? Also this is just measure when the motor is at TDC right?

 

ok I think I got it. So deck height is measured is thousandants from the top of the piston to the top of the cyclinder wall. so for example to find the deck height displacement you can use the formula

bore X bore X deck height (mm) X .0031416
--------------------------------------------------
4

correct?

Now since compression is dealt with deck height displacement you would use formula

Cylclinder displacement + deck height displacement + Head CC's
--------------------------------------------------------------------------
Deck Height displacement + Head CC's

correct?

Ok now if you had added a shorter stroke by replacing a crank in a B18C1 say with a B17 this affects Deck height and would increase it which would cause the compression to go down right?

Correct me if I'm wrong

 

Deck height doen't have to do with the piston or pin...it is from the center of the main journal
to the top of the block....Once you know that and your stroke...you can determine rod length
and pin placement....

 

Ok if your trying to put a b17 crank in a b18c your problem is going to be rod length the piston won't get pushed to the top..compression will allready be less because
of stroke....Have you thought about b20a3 crank and b16 rods and pistons ???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bully &raquo;</TD></TR><TR><TD CLASS="quote">Ok if your trying to put a b17 crank in a b18c your problem is going to be rod length the piston won't get pushed to the top..compression will allready be less because
of stroke....Have you thought about b20a3 crank and b16 rods and pistons ???</TD></TR></TABLE>


I was just using the B17 crank in the B18c1 as a example of decreasing deck height which affects compression?

I know that rod length is a issue but I was more interested in the facts of what deck heigth was used for and how it correlates to compression.

Ok so the the length from the top of the piston to the top of the cyclinder wall is measured in thousants to determine deck volume of each cyclinder right? Where you would use the plexiglass sheet and measure with placing a light oil and taking down what the meaurement is.

So then the main things that affect compression are rod length, stroke, deck height, bore, head gasket, and block CC's. Am I missing anything?


Modified by wicked B16 at 7:27 PM 11/12/2003


Modified by wicked B16 at 7:27 PM 11/12/2003

 

you win

 

head cc's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mmuller &raquo;</TD></TR><TR><TD CLASS="quote">head cc's</TD></TR></TABLE>thanx man, just bored and was looking up engine theory

 

check this out:
http://www.2strokeheads.com/Deck%20Height.html

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wicked B16 &raquo;</TD></TR><TR><TD CLASS="quote">ok I think I got it. So deck height is measured is thousandants from the top of the piston to the top of the cyclinder wall. so for example to find the deck height displacement you can use the formula

bore X bore X deck height (mm) X .0031416
--------------------------------------------------
4

correct?

Now since compression is dealt with deck height displacement you would use formula

Cylclinder displacement + deck height displacement + Head CC's
--------------------------------------------------------------------------
Deck Height displacement + Head CC's

correct?

Ok now if you had added a shorter stroke by replacing a crank in a B18C1 say with a B17 this affects Deck height and would increase it which would cause the compression to go down right?

Correct me if I'm wrong
</TD></TR></TABLE>

dont forget head gasket cc's