mk1trb

Will they fit in a silvertop zetec

Ben26

if its a 2.0 then yes

luke19790_3

Yes

mk1trb

what about the st170 pistons and rods then as there the same arent they?

luke19790_3

Yes they will fit

Turbo Zetec

iTrader: (1)

they're not the same as the Focus RS rods + pistons, but they are the same bore and big end sizes so they will fit.

And just to note, ST170 pistons are not forged, they're only normal cast ally the same as any other zetec, although they are a unique design.

rsmark86

iTrader: (3)

With the st170's won't the comp ratio be wrong in a silvertop? Or will it be like karlos's set up with 1.8mm frs gasket?

Karlos G

iTrader: (4)

ST170 pistons are high pressure cast (like RST ones) so are a fair bit stronger than normal Zetec ones, the rods are sinter-forged.

rsmark86

iTrader: (3)

So karlos, would they work in a silvertop with the same head gasket as you?

Would make a very cheap 300bhp engine if they did

crazycage

yes they would

Karlos G

iTrader: (4)

I have no idea what the CR would be, physically yes it seems it would all fit but beyond that I don't know mate.

Seeing as the black top has the better head and the ST pistons and rods are in a black top bottom end it doesn't make any sense to retro fit them to a silver top does it?! lol

In this case James is trying to keep his silver top so he doesn't have to change any of his ancillary setup which is fair play.

Turbo Zetec

iTrader: (1)

Mahle Pressure cast pistons would be 84P (like the Focus RS), whereas the st170 pistons are 84L, making them normal cast

studabear

So what do you think is a safe limit for st170 pistons?

Turbo Zetec

iTrader: (1)

apparently over 300bhp, but until someone pushes them over their limit, we won't know

rsmark86

iTrader: (3)

from what i read is at 9-0-1 mapped correctly they are upto 350bhp

but i guess 300bhp would be a safe limit

karlos for him it would work well then, but for anyone else they might aswell fit a blacktop.........

my gotech has the stuff to activate vvt already done so im thinking of building a st170 engine with forged pistons and rods and decent valve springs as a later swap when i get bored........

sitech says the vvt and turbo is awesome

Karlos G

iTrader: (4)

I stand corrected! lol Interesting then that they will take 350bhp.
Simon at Sitech pushed them over their limit, 355bhp.

fordcozyjohn

sorry to but in but can any one help me will the cams from a fista 1.6 zetec s fit my gf 1.6 zetec 04 focus ?

studabear

probably, but best checking with fords

fordcozyjohn

ok thanks m8

rsmark86

iTrader: (3)

i dont think so bud, isnt the 04 focus a normal zetec and the zetec s is a zetec se (yamaha engine) totally different if so

mp1

I'm glad somebody asked this as im looking at turboing an st 170 engine for my mk4 escort build!
Mmmm.the only question is over the vvti..to run or not to run??

studabear

do it, mines just made 247bhp @wheels, 14.5psi boost, no vvt tho

rsmark86

iTrader: (3)

Gotech mfi pro and pro x, have a built in function to activate the VVT, and I think dta has full control over it

I say be different and keep it

Frs internals with decent valve springs and gaskets with frs plugs and should see good figures

There was a guy running 390bhp on a stock frs bottom end not long ago

Karlos G

iTrader: (4)

Lose the ST head all together, again after speaking with Simon @ Sitech he advised against using them as they warp at the first sign of heat making them unreliable when turbo'd.
Fit a black top head, 1.8mm FRS Head Gasket FINIS 1361410, ARP rod bolts and your good for 350bhp with the correct turbo etc.

rsmark86

iTrader: (3)

Oh, I really wanted VVT

But Simon knows his stuff so best too Listen

Karlos G

iTrader: (4)

I did too, but when the voice of experience advises against it... you listen! lol

rsmark86

iTrader: (3)

Yeh, he has the best experience with it so best too listen

crazycage

We have no warped head problems with Ricks st170 turbo and my old one was fine too

rsmark86

iTrader: (3)

I would only want 350bhp ish, and try and keep some response and have it rev well

project rs

so you going to use a 170 head on the next engine or blacktop, that is if you ever get your finger out again and build that bottom end you keep promising p.s 30ft of 40x40 box for the brace dimensions to follow

crazycage

Blacktop for me

Billybob1982

Would rs pistons fit the conrods on the st170 and would it be worth it doing a blacktop head St 170 block turbo

Turbo Zetec

iTrader: (1)

Focus rs pistons will not fit st170 rods unfortunately