anyone tell me the difference if any between 18 zetec and 2.0 zetec heads, other than 130 brake cams in 2.0?? is the combustion chamber in the head different size?? i know differences in block.

cheers boys n girls!!!!

 

there interchangable, no real difference, the chamber does have a slightly different volume, but nothing major...

 

defo?? me mate reckons the valve positions are differnet??

will this affect compression ration since chamber will be differnet??

 

1800 is about 43 to 45 cc

2000 is ually 45 to 47cc chambers, bar that theres naff all in it.!
so putting a 1800 head on a 2 litre takes the CR up slightly..

valves positions are the same,
very very early 1800's did have a slightly different chamber again, but there all so old now your unlikely to see one..

Stu

 

Are you 100% sure about the combustion chamber on the different heads? I´ve been looking for ages for info on this, no luck until now.

A 1.8 egnine has a CP ratio of 10.0:1

Wich means that with combustion a chamber of 45cc a compressed cylinder head gasket of 0.96mm thick would be needed to reach 10.0:1

45cc = 0,96mm for 10.0:1

44cc = 1,15 mm for 10.0:1

43cc = 1,35 mm for 10.0:1

Above figure on a standard engine with a 88mm stroke and 80.6mm bore

So using a 2.0 head with 1.8 block would give you the following:

47cc combustion of 2.0 head

0,96 mm = 10.48:1

1,15 mm = 10.29:1

1,35 mm = 10.10:1

46cc combustion of 2.0 head

0,96 mm = 10.67:1

1,15 mm = 10.47:1

1,35 mm = 10.27:1

45 cc combustion of 2.0 head

0,96mm = 10.86:1

1,15 mm = 10.65:1

1,35 mm = 10.44:1

Above figure on a standard engine with 88mm stroke and 84.8 mm bore

 

I'm certain, seen enough of em.!

you wanna bear in mind, the manufacuring tolorances do varey a fair wack, but those measurments are in the ball park average..

youll not really notice much by swapping either head.

 

what you acually trying to achieve. ?, highest CR using bolt on, swappable parts. ?

Stu

 

Do you know the thickness of the head gasket when compressed? In the formula Ford championship a minium thickness of 1.54mm (compressed Standard Ford gasket) is allowed, sounds pretty thick does it not? Minimum combustion chamber allowed is 42.5cc when the sparkplug is fitted.

Im asking since my head has been skinned 1mm and i wanna use a 2.0 bottom.

 

1.54 dont sound far off, formula ford, just uses essencially a standard engine, bar rod bolts, and dry sump so nothing to wierd or wonderful. got one in the garage if you want one.!

Sure it been skimmed by 1mm, it would have to be astronimically bent to need 1mm..! what was the reason for such a big skim.. ?

 

1mm it is, only to raise the compression