1.7 head on 1.4 block?

[Stinkypaul]

Hi I’m a newbie on here so sorry if it’s already been asked but I’m wanting to know if the 1.7 head fits on the 1.4 block? My older son races 1.7 pumas and the youngest lad is currently building a 1.4 fiesta (1.4 is the upper cc limit he’s allowed to race) I’ve fitted the 1.7 inlet to his fiesta and a fourbranch exhaust manifold but can’t help wonder if the 1.7 head will fit and give any advantage (such as bigger valves and obviously vct)

 

[Wild E. Coyote]

The 1.7 head, to the best of my knowledge will not fit onto 1.4 block. Even if it did, it would bring CR drop.

The heads for 1.25, 1.4 and 1.6 are interchangeable. THe 1.25 head on 1.4 block will give you CR increase...

 

[siju]

As far as I know Coyote is right. You can't put a 1.7 head on another zetec-se engine. As also said with the 1.25 head you'll get higher compression ratio but the 1.6 head will give larger valves.

Alex

 

[Dziku]

Any specyfics on whats the difference between 1.7 heads and the rest? Can it be modified?
Couse with 1.6 block, ecoboost rods, vauxhall pistons and 1.7 head you could get the longblock for 300hp and because of vvt with good spool.
Also, can anyone know combustion chamber sizes of 1.6 and 1.7? And compressed headhaskets thicknes?

 

[mmc757]

A cheap way to learn more about this idea would be to compare head gaskets. Order a 1.7 head gasket and hold it up to your 1.4 block (if its still open) and look at the differences.

 

[siju]

I think that the oil and water line holes don't line up between 1.7 and the rest of the zetec-se (1.4-1.6-1.25).
Also I think it's cheaper to just buy forged rods-pistons for 1.7 (about 1200pounds) instead of doing the mix and match.

 

[Dziku]

100£ for rods, another 100 for pistons, 100 for 1.6, for the block and 150 for gaskets etc, so you can get 300hp longblock for 500£ if you arecrafty enough...

 

[siju]

I get your point but are you sure the st180 rods and pistons can be fitted to a 1.6 zetec se?

 

[Dziku]

If deck height is same as ecoboost(ill have to messure this weekend) then yes, rod bearings are the same, rods are 134mm long vauxhall pistons are 27.5mm height according to online catalogs..

 

[siju]

It sounds interesting. What crank do you plan to use? St180 or zetec se 1.6? And what Vauxhall model are the pistons from?

 

[Dziku]

Crank depends on combustion chamber size, we can go 1.6k no matter n/a or ecoboost) with low compression ratio, or 1.7 crank with sligthly higher, that is why i ask for head cc's.
Pistons from corsa d tubo, meriva opc etc(z16let, a16ler, and so on, all same pistons)...

 

[siju]

As far as I know (but I am not sure) the 1.6 due to higher compression ratio 11:1 must have smaller chamber than the 1.7 (10.3:1).

 

[Dziku]

As far as I know (but I am not sure) the 1.6 due to higher compression ratio 11:1 must have smaller chamber than the 1.7 (10.3:1).

Or higher pistons, without messurements we're going blind.
I dont fancy to buy 3 engines just for curiosity, but i suspect it will end this way, because no one knows anythig beside "put frp cams and manifold" or "swap to 2.0"...

 

[siju]

Yeah that's right. Before buying 3engines though I would suggest taking to lightning motorsport. He rebuilds/tunes zetec se engines and he might know. He has a steel sleeve kit to rebore the 1.7 to a bit bigger piston diameter so he has put some work into these engines.