Anyone KNOW about ST170 engine spec/rumours? Will?
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Just want to confirm a few rumours regarding ST170 engines as there's a lot of info floating about that no one seems to be able to confirm.
I have just bought a ST170 engine for turbo charging so...
Do they have uprated valve springs?
Do they have stronger or steel rods?
Are they higher comp. ratio?
Are the blocks any dfferent to standard?
What exactly needs doing to stop the VVT?
Anything else worth knowing? Cheers
I have just bought a ST170 engine for turbo charging so...
Do they have uprated valve springs?
Do they have stronger or steel rods?
Are they higher comp. ratio?
Are the blocks any dfferent to standard?
What exactly needs doing to stop the VVT?
Anything else worth knowing? Cheers
Last edited by XRT_si; 08-10-2008 at 11:36 PM.
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it's not 'on-off' - it's variable cam phase +/- 20degrees (or it might be 20deg retard only) controlled by a PWM output from the ecu. This opens/closes the solenoid by variable amounts, adjusting oil flow/pressure into the cam pulley and pushing out/letting in a sprung helix arrangment which causes a rotation of the shaft relative to the pulley.
I *think* from memory that with no PWM output / solenoid shut, the shaft defaults to fully retarded.
Valve springs are '10% uprated' according to ETIS, but from what rate I don't know.
Block is the same as 2.0L black top, head has smaller combustion chambers to give 10.5:1 compression iirc.
Rods are sinter-forged like in the zetec-se.
I *think* from memory that with no PWM output / solenoid shut, the shaft defaults to fully retarded.
Valve springs are '10% uprated' according to ETIS, but from what rate I don't know.
Block is the same as 2.0L black top, head has smaller combustion chambers to give 10.5:1 compression iirc.
Rods are sinter-forged like in the zetec-se.
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Just want to confirm a few rumours regarding ST170 engines as there's a lot of info floating about that no one seems to be able to confirm.
I have just bought a ST170 engine for turbo charging so...
Do they have uprated valve springs?
Do they have stronger or steel rods?
Are they higher comp. ratio?
Are the blocks any dfferent to standard?
What exactly needs doing to stop the VVT?
Anything else worth knowing? Cheers
I have just bought a ST170 engine for turbo charging so...
Do they have uprated valve springs?
Do they have stronger or steel rods?
Are they higher comp. ratio?
Are the blocks any dfferent to standard?
What exactly needs doing to stop the VVT?
Anything else worth knowing? Cheers
![Top](https://passionford.com/forum/images/smilies/smile011.gif)
Yes, they are stronger than normal Zetec springs but dodnt know the exact strength.
Yes forged rods. Mine held 291bhp without issue, although I upgraded later just to be sure.
10.5:1 ratio
Blaock wise I dont think so, although they do have oil spray bar for the pistons, which is a nice addition.
To truely eliminate the VVT you need to fit a venrier pulley on the inlet cam.
Anything else worth knowing: the heads are alot better than the Zetec's and dont need to be fettled. Dont use the standard inlet, as the rubber bungs come off the dual tract inlet and get stuck in the inelt runners. The port spacings are different from the Zetec, so inlets from those dont work. I got mine custom made by Danny B.
If you want anymore info let me know, as I went down this road about 3 years ago now... and I'm still loving it
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ah, another thing... the pistons are not forged ![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
the block is definately not the asme as the mondeo blacktop, but appears to be the same as the US Focus block. i haven't had a UK focus block yet to compare to though.
the rods are US length too, the small ends are 20mm
all 2.0's have oil spray jets![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
Why are you using the st170 out of curiosity? are you after monster power?
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
the block is definately not the asme as the mondeo blacktop, but appears to be the same as the US Focus block. i haven't had a UK focus block yet to compare to though.
the rods are US length too, the small ends are 20mm
all 2.0's have oil spray jets
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
Why are you using the st170 out of curiosity? are you after monster power?
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I think most of the questions have been answered above!
To eliminate VVT you need to block the oil pressure feed to the inlet cam - i used a grub screw on mine. You'll also need a machinist to turn you up an adaptor to drop in the resulting gap when you remove VVT pulley then fit a vernier pulley and dial in accordingly
To eliminate VVT you need to block the oil pressure feed to the inlet cam - i used a grub screw on mine. You'll also need a machinist to turn you up an adaptor to drop in the resulting gap when you remove VVT pulley then fit a vernier pulley and dial in accordingly
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MD COS: No the pistons are high pressure cast, they are stronger than the 2.0 Zetec ones, but aren't indestructable.
Will: Have you gotten rid of the VVT on the Focus?
Will: Have you gotten rid of the VVT on the Focus?
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Thanks for the sound info guys!
MDCOS - I just got the engine at a very good price, cheaper than getting uprated valve springs for the 2.0 Silver Top I now have sitting next to it![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
Simon - Cheers for the great info, guess my next question is what are the limits to these parts? At 291bhp was it still on standard valve springs? Has anyone pushed the standard rods etc...
Also did you uprate the rod bolts as I've heard they are uprated too?
Also very interesting info on the inlet, didnt know that. Guessing ill have to have an inlet made, is there no way of at least salvaging some of the zetec inlet? Cheers again!
MDCOS - I just got the engine at a very good price, cheaper than getting uprated valve springs for the 2.0 Silver Top I now have sitting next to it
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
Simon - Cheers for the great info, guess my next question is what are the limits to these parts? At 291bhp was it still on standard valve springs? Has anyone pushed the standard rods etc...
Also did you uprate the rod bolts as I've heard they are uprated too?
Also very interesting info on the inlet, didnt know that. Guessing ill have to have an inlet made, is there no way of at least salvaging some of the zetec inlet? Cheers again!
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Thanks for the sound info guys!
MDCOS - I just got the engine at a very good price, cheaper than getting uprated valve springs for the 2.0 Silver Top I now have sitting next to it![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
Simon - Cheers for the great info, guess my next question is what are the limits to these parts? At 291bhp was it still on standard valve springs? Has anyone pushed the standard rods etc...
Also did you uprate the rod bolts as I've heard they are uprated too?
Also very interesting info on the inlet, didnt know that. Guessing ill have to have an inlet made, is there no way of at least salvaging some of the zetec inlet? Cheers again!
MDCOS - I just got the engine at a very good price, cheaper than getting uprated valve springs for the 2.0 Silver Top I now have sitting next to it
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
Simon - Cheers for the great info, guess my next question is what are the limits to these parts? At 291bhp was it still on standard valve springs? Has anyone pushed the standard rods etc...
Also did you uprate the rod bolts as I've heard they are uprated too?
Also very interesting info on the inlet, didnt know that. Guessing ill have to have an inlet made, is there no way of at least salvaging some of the zetec inlet? Cheers again!
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[quote=XRT_si;3644899]Thanks for the sound info guys!
MDCOS - I just got the engine at a very good price, cheaper than getting uprated valve springs for the 2.0 Silver Top I now have sitting next to it![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
/quote]
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
MDCOS - I just got the engine at a very good price, cheaper than getting uprated valve springs for the 2.0 Silver Top I now have sitting next to it
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
/quote]
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
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Simon - Cheers for the great info, guess my next question is what are the limits to these parts? At 291bhp was it still on standard valve springs? Has anyone pushed the standard rods etc...
Also did you uprate the rod bolts as I've heard they are uprated too?
Also very interesting info on the inlet, didnt know that. Guessing ill have to have an inlet made, is there no way of at least salvaging some of the zetec inlet? Cheers again!
Also did you uprate the rod bolts as I've heard they are uprated too?
Also very interesting info on the inlet, didnt know that. Guessing ill have to have an inlet made, is there no way of at least salvaging some of the zetec inlet? Cheers again!
The standard rods will take 300bhp with standard bolts.
Ian Howell (Area Six) supplies uprated valve springs if you want them. He also does a really nice inlet to. As Crazycage has said, the Rover inlet manifold is a popular choice as well.
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Cheers for the info, what boost and what turbo did you make 300bhp on?
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
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Cheers for the info, what boost and what turbo did you make 300bhp on?
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
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si- keep sat free, we'll head over jb's drop diff off get my seats, turbo and calipers lol
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yes, there are a lot of roumours about ST170 engines.
i used to build ST internals into silvertop blocks and use silvertop heads to loose the VVT setup, they are NOT electronic operated and use centrifugal force with pressure opperated gel to make the cam pulleys advance/retard.
they are electronicaly sensed to advance/retard ECU effects on fuel/spark maps.
they ran forged rods and pistons, longer rods and very shallow pocketed pistons and look very very well engineered for a mass produced motor.
ST170`s do have completley different heads to any other 2.0 zetec (which is basicaly a modded black top 2.0)
if you look on a petruding front facing lug on cylnder head it has SVT stamped into it, this proves an ST170 head.
they have high lift cams, stronger springs, slight change in port shape and one off head cast that accepts VVT setup, normal non ST cams/valvetrain in not compatable in ST heads, journals and pulleys etc simply do not mate up with the head.
each head was specificaly biult by hand and shipped to be mated to botom end and fitted to production car.
any questions at all you may have, please ask![Grin](https://passionford.com/forum/images/smilies/icon_smile.gif)
regards Sean
i used to build ST internals into silvertop blocks and use silvertop heads to loose the VVT setup, they are NOT electronic operated and use centrifugal force with pressure opperated gel to make the cam pulleys advance/retard.
they are electronicaly sensed to advance/retard ECU effects on fuel/spark maps.
they ran forged rods and pistons, longer rods and very shallow pocketed pistons and look very very well engineered for a mass produced motor.
ST170`s do have completley different heads to any other 2.0 zetec (which is basicaly a modded black top 2.0)
if you look on a petruding front facing lug on cylnder head it has SVT stamped into it, this proves an ST170 head.
they have high lift cams, stronger springs, slight change in port shape and one off head cast that accepts VVT setup, normal non ST cams/valvetrain in not compatable in ST heads, journals and pulleys etc simply do not mate up with the head.
each head was specificaly biult by hand and shipped to be mated to botom end and fitted to production car.
any questions at all you may have, please ask
![Grin](https://passionford.com/forum/images/smilies/icon_smile.gif)
regards Sean
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yes, there are a lot of roumours about ST170 engines.
i used to build ST internals into silvertop blocks and use silvertop heads to loose the VVT setup, they are NOT electronic operated and use centrifugal force with pressure opperated gel to make the cam pulleys advance/retard.
they are electronicaly sensed to advance/retard ECU effects on fuel/spark maps.
i used to build ST internals into silvertop blocks and use silvertop heads to loose the VVT setup, they are NOT electronic operated and use centrifugal force with pressure opperated gel to make the cam pulleys advance/retard.
they are electronicaly sensed to advance/retard ECU effects on fuel/spark maps.
Why not just use the black top head ?
With the VVT I understand that its not simply on or off, however I know a few guys who either have their VVT on a manual switch or it is switched to the ON position using the shift light function on ECU's not capabale of controlling VVT
What effect does the bolt in the oil way have ?
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i used ST internals into silvertop block as the engine went into mk3 escort and was much much more adaptable than the black top block.
u used the silvertop head for reasons i cant remember but after trying to use 3 different heads i settled on the origional silver top head with Auto inlet or exhaust cam fitted, i think it was due to the later cam timing pulleys not being in correct position with black top/ST top end and early silvertop block/crank?
cant remember 100% but at the time simply no combination would work except ST pistons/rods in a modded silvertop block and head assembly.
engine was on Dellorto 45`s, maby this made a difference at the time? memory serves me no ideas at this time.
Sean.
u used the silvertop head for reasons i cant remember but after trying to use 3 different heads i settled on the origional silver top head with Auto inlet or exhaust cam fitted, i think it was due to the later cam timing pulleys not being in correct position with black top/ST top end and early silvertop block/crank?
cant remember 100% but at the time simply no combination would work except ST pistons/rods in a modded silvertop block and head assembly.
engine was on Dellorto 45`s, maby this made a difference at the time? memory serves me no ideas at this time.
Sean.
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simon170 - still running VVT on the focus!
I took it off on the 500bhp engine i was building earlier in the year![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
I gave mine relentless abuse at Oulton Park on Wednesday, 8000rpm in 3rd, 4th and 5th on standard ST170 valvetrain without problem
I took it off on the 500bhp engine i was building earlier in the year
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
I gave mine relentless abuse at Oulton Park on Wednesday, 8000rpm in 3rd, 4th and 5th on standard ST170 valvetrain without problem
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#31
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ST170 Rods are mix of ali nickel and steel powder sintered, cold forged then big ends are snapped then the lot is machined. Powder sintered rod is cheaper to mass manufacture, lighter and good tensile strength. Pistons are same with different metal ratios mostly being ali. Will take lots of rev but shocks, knocks and det will break them easier.
The forged EN24 steel is heavier and more expensive to produce is stronger coping with higher tensile and compression forces at higher temperatures.
HTH
The forged EN24 steel is heavier and more expensive to produce is stronger coping with higher tensile and compression forces at higher temperatures.
HTH
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Cheers for the info, what boost and what turbo did you make 300bhp on?
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
BTW the pistons are high-pressure die cast.
Will - Nice one
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Cheers for the info, what boost and what turbo did you make 300bhp on?
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
As this contrasts with what Crazycage has said?
I built a zetec turbo before and still got loads of parts like 1.8 inlets knocking around, guessing ill have to knock up a Rover one!
Paul - The pistons ARE mahle, and it IS printed on the inside of them. Just had a look
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
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Lol - for those in doubt as to what sort of abuse a standard ST170 valvetrain can tolerate may want to watch this ![](https://passionford.com/forum/images/smilies/roi.gif)
http://uk.youtube.com/watch?v=aVrk8I6m2sQ
![](https://passionford.com/forum/images/smilies/roi.gif)
http://uk.youtube.com/watch?v=aVrk8I6m2sQ
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What C/R are you running mate? Mine runs 8.8:1
Will - Well peddled
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EDIT: I could have sworn that Ian dropped the comp lower than that when it was rebuilt Will?
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What C/R are you running mate? Mine runs 8.8:1
Will - Well peddled
I assume it was you driving lol, was going well. Sounds like there was some vibration in the corners? Was that Neils track car infront of you that was looking a bit unwell?
EDIT: I could have sworn that Ian dropped the comp lower than that when it was rebuilt Will?
Will - Well peddled
![Big Grin](https://passionford.com/forum/images/smilies/icon_mrgreen.gif)
EDIT: I could have sworn that Ian dropped the comp lower than that when it was rebuilt Will?
It was me pedalling - i think it was alright to say it was my first time properly driving on track
![Big Grin](https://passionford.com/forum/images/smilies/icon_biggrin.gif)
Not entirely sure what that knocking is - felt like tyre scrub - could well be as i'm now on R888s with the stiffer sidewalls....