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Old Oct 4, 2008 | 08:27 AM
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Default Zetec+st170

Can a st170 head be fitted to a 2.0l zetec and would there be any gain in doing this???

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Old Oct 4, 2008 | 08:33 AM
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Originally Posted by woolford
Can a st170 head be fitted to a 2.0l zetec and would there be any gain in doing this???

Thanks
it fits on the black top bottem end ,has wild cams much bigger inlet ports and bigger valve + vvt if you want to run it
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Old Oct 9, 2008 | 04:41 PM
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Originally Posted by crazycage
it fits on the black top bottem end ,has wild cams much bigger inlet ports and bigger valve + vvt if you want to run it
If you don't want to use the VVT can the ST's head just be fitted as per the normal 2litre head? sounds like quite a good upgrade idea
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Old Oct 9, 2008 | 07:26 PM
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The head physically fits on the silver or black top engine, but for the earlier engine you need to be creative with the cam belt routing. It's not rocket science though.
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Old Oct 9, 2008 | 08:03 PM
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Originally Posted by pa_sjo
The head physically fits on the silver or black top engine, but for the earlier engine you need to be creative with the cam belt routing. It's not rocket science though.
doesn't the ST170 run different rods/pistons? any idea whether the compression would get higher/lower on the stock 2litre with the ST head fitted outta interest?
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Old Oct 9, 2008 | 09:21 PM
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Higher or lower than what? It'd be higher than a stock 2L zetec..
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Old Oct 9, 2008 | 09:41 PM
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Originally Posted by pa_sjo
Higher or lower than what? It'd be higher than a stock 2L zetec..
so putting a ST170 on a standard 2litre would not only improve the flow but give it a higher compression- now your talking
i own a mk1 2litre so just looking at good upgrades.
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Old Oct 9, 2008 | 09:44 PM
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It'd give it a similar compression to that of the full st170 engine! Approx. 10.5:1!
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Old Oct 9, 2008 | 09:59 PM
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Originally Posted by pa_sjo
It'd give it a similar compression to that of the full st170 engine! Approx. 10.5:1!
just been doing some googling, the 2litre is 9.6:1 vs the ST170s 10.2:1
I'd guess the head alone would get it between the two seeing as the pistons/rods added to the ST where also high comp from wot i've read.
could do with a skim or two on the head aswell
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Old Oct 9, 2008 | 10:07 PM
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UK 2L isnt 9.6:1, that's the US one.. UK is ~10:1
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Old Oct 9, 2008 | 10:13 PM
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Originally Posted by pa_sjo
UK 2L isnt 9.6:1, that's the US one.. UK is ~10:1
thats even worse then if the facts on this site are right.
you sure it would raise the compression?
the facts on this site look pretty good to me- could be wrong though.
http://www.fordst170.co.uk/specs.php
10.2:1 from 10:1 with high comp pistons/rods and a different head says to me maybe the head wouldn't alter the compression at all.
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Old Oct 9, 2008 | 10:15 PM
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You won't know what it is until you build it and measure it. The facts are, the ST170 head has a smaller combustion chamber than a normal zetec, so the CR WILL be higher.
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Old Oct 9, 2008 | 10:23 PM
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Originally Posted by pa_sjo
You won't know what it is until you build it and measure it. The facts are, the ST170 head has a smaller combustion chamber than a normal zetec, so the CR WILL be higher.
fair enough, cheers for the info
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Old Oct 11, 2008 | 02:46 PM
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Actually the ST170 (european) head has exactly the same head volume as the 2.0l (european) Blacktop head. AFAIK the variation in CR (0.2) comes from the difference in rod, piston and headgasket dimensions.

The ST170 uses American dimension rods (and pistons to suit) not the same as European ones.

Martin
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