ST170 Turbo Engine Rebuild - CGI - thinking of selling up!!
#1
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Westfield ST170 Turbo Engine Rebuild - CGI - all back on track
I've covered over 5'000 miles in the Westfield this year as Ive been up and down the country to a few shows as well as through Belgium and to Le Mans so I've decided to upgrade the engine over winter, (I get bored easy).
I've been running the car with circa 350 - 400bhp depending on boost but would like a bit more power to propel me into the low 10's even a 9
With the current spec I managed an 11.07 @138 at a RWYB at Elvington on road tyres and I've also manages a few 11.1's at Pod too.
I'm looking to reliably get over 500bhp out the engine when I'm done which should be a breeze with the spec I already have and what I'm planning.
The easy option would be to just slap on a GT30 and have done but I am looking at building a top spec motor with the best of everything.
I'll be using my current inlet system with a larger Jenvey throttle body and changing my head, cams, exhaust manifold and turbo.
I'm also going to run a slightly higher comp ratio than my pervious engine.
It's a bit drastic but I've always wanted to go this route anyhow.
I'll be using a silvertop block mated to an ST170 head with electric water pump setup to get round the belt fouling the waterpump. No NOS at this stage but I may change my mind.
Silvertop bottom ends have larger maincaps which is the reason for going this route.
Here are some pictures of the ST170 head I recently bought.
This will be getting larger valves and a ported by CNC heads over winter.
I'll be taking off the Variable valve timing which is an easy job.
It's worth noting that these heads flow better than the Cosworth head as they were developed by the Special Vehicle Team in America hence the Focus SVT branding in the states.
I've been told these heads are good for well over 700bhp once ported if I wanted to go that mad
I'll update as and when things move along
I've been running the car with circa 350 - 400bhp depending on boost but would like a bit more power to propel me into the low 10's even a 9
With the current spec I managed an 11.07 @138 at a RWYB at Elvington on road tyres and I've also manages a few 11.1's at Pod too.
I'm looking to reliably get over 500bhp out the engine when I'm done which should be a breeze with the spec I already have and what I'm planning.
The easy option would be to just slap on a GT30 and have done but I am looking at building a top spec motor with the best of everything.
I'll be using my current inlet system with a larger Jenvey throttle body and changing my head, cams, exhaust manifold and turbo.
I'm also going to run a slightly higher comp ratio than my pervious engine.
It's a bit drastic but I've always wanted to go this route anyhow.
I'll be using a silvertop block mated to an ST170 head with electric water pump setup to get round the belt fouling the waterpump. No NOS at this stage but I may change my mind.
Silvertop bottom ends have larger maincaps which is the reason for going this route.
Here are some pictures of the ST170 head I recently bought.
This will be getting larger valves and a ported by CNC heads over winter.
I'll be taking off the Variable valve timing which is an easy job.
It's worth noting that these heads flow better than the Cosworth head as they were developed by the Special Vehicle Team in America hence the Focus SVT branding in the states.
I've been told these heads are good for well over 700bhp once ported if I wanted to go that mad
I'll update as and when things move along
Last edited by AustenW; 07-04-2021 at 10:24 PM.
#2
Too many posts.. I need a life!!
Nice mate, love westfields and yours is especially cool.
Is going high comp going to affect boost levels which will affect torque? or is there something you hve planned to combat this??
Cheers Mike
Is going high comp going to affect boost levels which will affect torque? or is there something you hve planned to combat this??
Cheers Mike
#3
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fair play to you but surely you would be better of spending time/money improving the setup of the car so it can use all of its 400 horses, rather than giving it more power i assume its not gonna be able to handle until its doing 60/70mph. i think if you could get it launching harder off the line you could get your 10s, and that giving it another 100bhp might not be the best way to get the times you want.
either way, thats just my opinion, its your car, so cant really knock whatever you decide to do with it!
whats the score with the 170 head btw? having a big discussion on xrtwo.com about these engines/heads. whats involved in running one on a silver top bottom end? theyre suposed to be faarrrr better than the std zetec heads, and better than alot of so called performace heads you can buy off the shelf from engine builders?
either way, thats just my opinion, its your car, so cant really knock whatever you decide to do with it!
whats the score with the 170 head btw? having a big discussion on xrtwo.com about these engines/heads. whats involved in running one on a silver top bottom end? theyre suposed to be faarrrr better than the std zetec heads, and better than alot of so called performace heads you can buy off the shelf from engine builders?
#4
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can you use silver top cams int hese heads? its been a while since i had my rocker cover off, but im sure the cam caps are in a different arrangement? i might just be off my head though!
#5
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I want a responsive engine off boost hence the high comp route.
Just to note that Andy Nichols with his 800bhp fwd Rover is running high comp and 3 bar of boost and his car has the same torque as Rocket Ronnies Skyline. As proven on the dynopack at AET with Abbey Motorsport present.
I have had the car 3 years now and built it from scratch so its as set up as it can be. The best launch was a 1.7 sec 60 ft on street tyres that I use every day. I also drove the car to the event and home again. I might put some softer springs on the back for straight lining though in the future but thats all I can do apart from putting some huge Mickey Thompson drag tyres on it, which I don't fancy doing as its cheating IMO in a street legal class.
Once on the move it has plenty of traction so another 100 bhp should be fine.
Also the ST head is totally different and the cams are a different thickness on the bearing caps.
These heads are the future for Zetec turbo tuning. Massive flow potential from these.
They flow better in standard form than most big valve performance heads, (silver or black top).
They can flow more than a cossie head too
Just to note that Andy Nichols with his 800bhp fwd Rover is running high comp and 3 bar of boost and his car has the same torque as Rocket Ronnies Skyline. As proven on the dynopack at AET with Abbey Motorsport present.
I have had the car 3 years now and built it from scratch so its as set up as it can be. The best launch was a 1.7 sec 60 ft on street tyres that I use every day. I also drove the car to the event and home again. I might put some softer springs on the back for straight lining though in the future but thats all I can do apart from putting some huge Mickey Thompson drag tyres on it, which I don't fancy doing as its cheating IMO in a street legal class.
Once on the move it has plenty of traction so another 100 bhp should be fine.
Also the ST head is totally different and the cams are a different thickness on the bearing caps.
These heads are the future for Zetec turbo tuning. Massive flow potential from these.
They flow better in standard form than most big valve performance heads, (silver or black top).
They can flow more than a cossie head too
#6
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fair enough, 1.7 60ft is pretty impressive! i just had visions of it being a slag off the line, seen a cossie powered caterham launch and it was all over the place through 1st and 2nd gear.
the cams are a totally different breed of their own then? i know the S3 cams fit the S1/2 heads so obviously they cant fit the 170 head. are they bugger or small in the 170 head?
how does the variable cam timing system work on these then? is it just a signal from the ECU at xxxxrpm that controls it?
sorry for all the questions but you seem like a knowledgable bloke and nobody else ive spoken to knows much about these engines!
the cams are a totally different breed of their own then? i know the S3 cams fit the S1/2 heads so obviously they cant fit the 170 head. are they bugger or small in the 170 head?
how does the variable cam timing system work on these then? is it just a signal from the ECU at xxxxrpm that controls it?
sorry for all the questions but you seem like a knowledgable bloke and nobody else ive spoken to knows much about these engines!
#7
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Thread Starter
The ST cams have a thicker section on the last cap.
The VVT is triggered by a selenoid which allows oil to flow through the inlet cam into the pully wheel which makes it move at a desired RPM altering the cam timing.
Very impressive if you ask me.
This will all be removed and is a simple fix. I will be installing a standard set of Zetec Pulley wheels, (piper ajustables to be precise), I will also have to make up a collar to enable me to fit this to the inlet cam as it is totally different.
The oilway feed in the cam cap will be tapped and a 6mm grub screw threadlocked in to prevent the oil feed.
This will not interfear with the engine running at all, as each cam cap has its own bottom oil feed .
It will be easy to retro install the VVT if ever needed by doing this.
I also plan to bung off a couple of the sensor holes with either tapered grub screws or i'll make up some special blank off bungs
The VVT is triggered by a selenoid which allows oil to flow through the inlet cam into the pully wheel which makes it move at a desired RPM altering the cam timing.
Very impressive if you ask me.
This will all be removed and is a simple fix. I will be installing a standard set of Zetec Pulley wheels, (piper ajustables to be precise), I will also have to make up a collar to enable me to fit this to the inlet cam as it is totally different.
The oilway feed in the cam cap will be tapped and a 6mm grub screw threadlocked in to prevent the oil feed.
This will not interfear with the engine running at all, as each cam cap has its own bottom oil feed .
It will be easy to retro install the VVT if ever needed by doing this.
I also plan to bung off a couple of the sensor holes with either tapered grub screws or i'll make up some special blank off bungs
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#8
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Awesome work austen
have have you found the coil on plug scenerio? i presume they havent caused you any hassle?
what type are they? civic items?
PM me if you wish.
Cheers
Ryan
Car Looms UK
have have you found the coil on plug scenerio? i presume they havent caused you any hassle?
what type are they? civic items?
PM me if you wish.
Cheers
Ryan
Car Looms UK
#10
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Lovely car, watched i with intrest at totb.
Regarding flow figures. These are far from the be all and end all in terms of a heads peformance aren't they. I have no doubt that they are better than the normal (garbage) Zetec heads though The YB head takes a lot of beating, regadless of what flow figures may say.
Are you going to lenghten the rods to imrove the rod/stroke ratio?
Regarding flow figures. These are far from the be all and end all in terms of a heads peformance aren't they. I have no doubt that they are better than the normal (garbage) Zetec heads though The YB head takes a lot of beating, regadless of what flow figures may say.
Are you going to lenghten the rods to imrove the rod/stroke ratio?
#12
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Thread Starter
The coil on plug are Magnetti Marrelli items bought from Magnetti Marrelli Competition Systems.
I can do the coil pack holder bracket which goes in the centre of the rocker cover if anyone else decides to go this route. It's CNC machined out of high grade 5mm alloy, PM me for details.
Done over 5'000 miles now without missing a beat with this set up.
Not sure on tappet size? I'll just go measure one
He goes to the garage............................................ .........
There 30mm in diameter
As for head flow these heads are probably one of the best flowing 4cyl heads available, and yes possibly even better than the cosworth but thats for another thread.
Hardly anyone has started to highly tune these yet so lets wait and see
For details see
http://www.cncheads.co.uk/products.html
ST170 ported 183 CFM
Cosworth ported 158 CFM
Both using standard valves
I can do the coil pack holder bracket which goes in the centre of the rocker cover if anyone else decides to go this route. It's CNC machined out of high grade 5mm alloy, PM me for details.
Done over 5'000 miles now without missing a beat with this set up.
Not sure on tappet size? I'll just go measure one
He goes to the garage............................................ .........
There 30mm in diameter
As for head flow these heads are probably one of the best flowing 4cyl heads available, and yes possibly even better than the cosworth but thats for another thread.
Hardly anyone has started to highly tune these yet so lets wait and see
For details see
http://www.cncheads.co.uk/products.html
ST170 ported 183 CFM
Cosworth ported 158 CFM
Both using standard valves
#13
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going back to the VVT, somebody sugested on xrtwo.com that this would be useless if not used with the st170 management, but surely all it would take is a signal from the ecu at say 4500rpm or whatever it needs to be, to activate the solenoid. so surely something like a megasquirt V3 ecu with a programable output could be setup to use the standard VVT setup and cams?
interesting stuff. how much did that head cost you if you dont mind me asking? or more to the point, how much do they normally go for?
interesting stuff. how much did that head cost you if you dont mind me asking? or more to the point, how much do they normally go for?
#14
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Heads are rare on there own and you can expect to pay from between £450 to £1000+ for a full engine.
I got lucky with this find as its done virtually no miles.
I dont want to run the VVT so will be removing it completely.
Today I managed to tap the oil feed to the VVT and insert a grub screw to block off the oil feed. The oil feed is 4.9mm so I tapped it for an M6 and inserted a grub screw with thread lock.
See the centre of the blue o ring seal
I also pressed in a couple of 18mm core plugs to block up the hole for the VVT selenoid.
This is required to prevent oil leaking out of the rocker cover.
See where the oil feed comes out the centre of the head via a one way valve. This will not be needed.
While I was at it I also put a 17mm core plug where the cam sensor used to be as I will be running this on banked injection a sensor is not needed.
The ports are a similar diameter to a normal zetec but the port shape is completely different and far superior.
Thats it for now.
I got lucky with this find as its done virtually no miles.
I dont want to run the VVT so will be removing it completely.
Today I managed to tap the oil feed to the VVT and insert a grub screw to block off the oil feed. The oil feed is 4.9mm so I tapped it for an M6 and inserted a grub screw with thread lock.
See the centre of the blue o ring seal
I also pressed in a couple of 18mm core plugs to block up the hole for the VVT selenoid.
This is required to prevent oil leaking out of the rocker cover.
See where the oil feed comes out the centre of the head via a one way valve. This will not be needed.
While I was at it I also put a 17mm core plug where the cam sensor used to be as I will be running this on banked injection a sensor is not needed.
The ports are a similar diameter to a normal zetec but the port shape is completely different and far superior.
Thats it for now.
#17
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Very good to see As you know Austen, you simply can't have too much power. Going from 11.1 sec runs down to the low 10s isn't something you can achieve by softening rear suspension or "launching better"! With 1.7 sec 60ft times you clearly have it leaving the line well, so power is the only solution here, retaining road legal tyres of course. High CR turbo engines aren't build often enough IMO, and beat any other layout IMO. If only I had a dyno to see how high a CR the Zetec could take before ignition control got impossible... This should be a brilliant engine, keep the updates coming! Ready for TOTB VI?
#18
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Originally Posted by heeman10
Very good to see As you know Austen, you simply can't have too much power. Going from 11.1 sec runs down to the low 10s isn't something you can achieve by softening rear suspension or "launching better"! With 1.7 sec 60ft times you clearly have it leaving the line well
#19
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We are going slightly off topic now but have you guys ever heard of launch control, traction control and boost control, beacause I'm using all three.
As for times the car has a ten in it at present looking through all my timing slips as I never seem to get a perfect run.
Using my best launch, 60ft, 1/8th etc I'd be doing a 10 something
As for times the car has a ten in it at present looking through all my timing slips as I never seem to get a perfect run.
Using my best launch, 60ft, 1/8th etc I'd be doing a 10 something
#21
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Sorry if it seemed a bit sharp but it amazes me how people seem to think they no more about my own car and its set up than I do.
Back to topic anyway
Back to topic anyway
#22
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do u need to do anymore reinforcement to the chassis?
does anyone know the limitation of the shell? i.e flex etc etc
or is the triangulated chassis pretty strong?
Also what box you hoping to be using? a t5 still? i presume that is what you are running now?
does anyone know the limitation of the shell? i.e flex etc etc
or is the triangulated chassis pretty strong?
Also what box you hoping to be using? a t5 still? i presume that is what you are running now?
#23
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Originally Posted by AustenW
Sorry if it seemed a bit sharp but it amazes me how people seem to think they no more about my own car and its set up than I do.
Back to topic anyway
Back to topic anyway
#24
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Thread Starter
do u need to do anymore reinforcement to the chassis?
Yes, already done
does anyone know the limitation of the shell? i.e flex etc etc
Its fibreglas so will flex if needed
is the triangulated chassis pretty strong?
Yes
Also what box you hoping to be using? a t5 still? i presume that is what you are running now?
I run a Quaife sequential
Let get back to topic now
Yes, already done
does anyone know the limitation of the shell? i.e flex etc etc
Its fibreglas so will flex if needed
is the triangulated chassis pretty strong?
Yes
Also what box you hoping to be using? a t5 still? i presume that is what you are running now?
I run a Quaife sequential
Let get back to topic now
#26
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Looks like the ideal ZT specification to me. We have run along very similar lines with Cols engine.
I take it you are replacing the disco potato with a Gt30? We are running the 30r with an external gate and a .63 housing. I find the response amazing for a turbo that can make that much horsepower.
Are you going to go for the stainless valves option in your CNC head? We did as i didn't fancy letting the stock (probaby two piece friction welded) exhaust valves deal with that extra heat.
Which leads me onto what else i would like to do on my next ZT... internal thermal coatings. I reckon there is a lot to be said for coating the face of at least the inlet valves. We spend all that effort trying to cool the inlet charge only to shoot it past a hot inlet valve at the last minute. I'm not sure how much cooler the inlet valve will run (need some cosworth/lotus type test facilities for that one!) but its got to be an area worth looking at.
Looking forward to seeing how you get on with this engine. Good to see other people pushing the boundries and not just sticking to those same old routes.
I take it you are replacing the disco potato with a Gt30? We are running the 30r with an external gate and a .63 housing. I find the response amazing for a turbo that can make that much horsepower.
Are you going to go for the stainless valves option in your CNC head? We did as i didn't fancy letting the stock (probaby two piece friction welded) exhaust valves deal with that extra heat.
Which leads me onto what else i would like to do on my next ZT... internal thermal coatings. I reckon there is a lot to be said for coating the face of at least the inlet valves. We spend all that effort trying to cool the inlet charge only to shoot it past a hot inlet valve at the last minute. I'm not sure how much cooler the inlet valve will run (need some cosworth/lotus type test facilities for that one!) but its got to be an area worth looking at.
Looking forward to seeing how you get on with this engine. Good to see other people pushing the boundries and not just sticking to those same old routes.
#28
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Been busy today.
Measured the combustion chamber in the head and it's 40cc so I can now work out what bowl I will need in my pistons to get the right comp ratio.
Also paint stripped, sand blasted and smoothened the rocker cover and removed the excess bits of metal ready for powder coating which has taken me all day.
Will post up picks soon once coated
Measured the combustion chamber in the head and it's 40cc so I can now work out what bowl I will need in my pistons to get the right comp ratio.
Also paint stripped, sand blasted and smoothened the rocker cover and removed the excess bits of metal ready for powder coating which has taken me all day.
Will post up picks soon once coated
#31
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Good work so far
Just had a look at those figures from CNC heads. According to them, a Zetec head flows more than a YB in std form - which as you will know - is total garbage.....
Rick.
Just had a look at those figures from CNC heads. According to them, a Zetec head flows more than a YB in std form - which as you will know - is total garbage.....
Rick.
#32
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Thread Starter
Heat shield is a modified HKS item
Here's a few pics of the rocker cover I've finished tonight.
First I stipped and sanded it down.
Then I got it powder coated silver by a friend,
I then rubbed it down to get all the small marks out of it until it was perfect and sprayed it in 2 pack solid chrome yellow.
Its come out mint.
Here's a few pics of the rocker cover I've finished tonight.
First I stipped and sanded it down.
Then I got it powder coated silver by a friend,
I then rubbed it down to get all the small marks out of it until it was perfect and sprayed it in 2 pack solid chrome yellow.
Its come out mint.
#33
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nice work!
You made it the same way like i did to get the VVT out of the engine!
http://www.st2000.de/vct%20umbau.htm
What kind of Camshaftwheel did you use.
I had build one for my own, cause i dont found a manuell setable.
Would like to see more pics, and facts of you one!
Cheers Mark
You made it the same way like i did to get the VVT out of the engine!
http://www.st2000.de/vct%20umbau.htm
What kind of Camshaftwheel did you use.
I had build one for my own, cause i dont found a manuell setable.
Would like to see more pics, and facts of you one!
Cheers Mark
#34
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Thread Starter
Will update soon.
I'm currently making up a carbon fibre rocker plug cover to hide my coil on plug set up.
Also going a different route with the block, sump etc.
Decided to go with a Nicosil Linered CGI WRC block and dry sump system for a sealed engine.
Best start saving
I'm currently making up a carbon fibre rocker plug cover to hide my coil on plug set up.
Also going a different route with the block, sump etc.
Decided to go with a Nicosil Linered CGI WRC block and dry sump system for a sealed engine.
Best start saving
#36
Advanced PassionFord User
Thread Starter
Been in the garage today and just about finished making the coil on plug mounting plate out of carbon fibre.
Will update in the week when my coils arrive.
I've gone for some inductive Magneti Marelli motorsport items.
They have been successfully used by a guy in the states on turbo'd motor producing over 600bhp so should be fine for what I want.
Will update in the week when my coils arrive.
I've gone for some inductive Magneti Marelli motorsport items.
They have been successfully used by a guy in the states on turbo'd motor producing over 600bhp so should be fine for what I want.
#38
Originally Posted by Rick
Good work so far
Just had a look at those figures from CNC heads. According to them, a Zetec head flows more than a YB in std form - which as you will know - is total garbage.....
Rick.
Just had a look at those figures from CNC heads. According to them, a Zetec head flows more than a YB in std form - which as you will know - is total garbage.....
Rick.
Also, when we produce a 500+ Zetec we only work the last inch of the port and fit slightly oversize valves. With a YBT you need to enlarge the throat to 25mm per port to get similar HP figures.
With regard to maximum achievable flow through the heads, whether Zetec silver top, YBT or St170, the figures will be something like this at 10" H2O.
Zetec silvertop 145CFM
YBT 195CFM
ST170 182CFM.
Yes, the YBT will achieve a huge flow figure, but in order to do this you need 29mm runners, and this causes low velocity and a very soggy feel (compared to Std). The ST doesn't need a huge port, and as such the velocities are still good and the engine will feel sharper.
Hope this helps provide an alternative perspective on potential.
#39
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hui, your english is to hard for me, for me little german man!
Which engine do you mean with the YBT? i never heard this code!
I have a little problem with my St170 enginge.
I mounted the HEGO Sensor down behind the engine (like on the first Zetec exhausts) but when i´m gone kick his As it glow´s realy hard red/yellow until under the car and incl. the HEGO Sensor and me messureing goes slightly to lean!
Up to which temperature the HEGO sensor will work?
Cheers Mark (sorry for this english!)
Which engine do you mean with the YBT? i never heard this code!
I have a little problem with my St170 enginge.
I mounted the HEGO Sensor down behind the engine (like on the first Zetec exhausts) but when i´m gone kick his As it glow´s realy hard red/yellow until under the car and incl. the HEGO Sensor and me messureing goes slightly to lean!
Up to which temperature the HEGO sensor will work?
Cheers Mark (sorry for this english!)
#40
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Sounds like it is going to be an incredible engine, especially with the new bottom end!!
Could you describe the water pump issue a little more please? Do you mean the cambelt fouls the waterpump?
Could you describe the water pump issue a little more please? Do you mean the cambelt fouls the waterpump?