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Silvertop zetec to ST170
austin man - 3/12/14 at 10:31 PM

Thinking of replacing the engine in the MK, have seen anST 170 engine for sale would this be a direct swap for the silvertop zetec engine or is there much work involved


Dusty - 3/12/14 at 11:55 PM

Idler for waterpump belt, different alternator bracket and a bit of fettling to match the inlet ports is about all. Can be some variation in the engine mount bolt holes but I got away with just a drill and file and re-used the old mounts. Easy swap.


kingster996 - 4/12/14 at 07:28 AM

And some way to run the vvt. There's a bolt on box available to control it.

Also, you'll need the windage tray from the Silvertop when you swap sumps (assuming yours is a lowered one)

I'll be doing this - starting with a silvertop then putting in the ST170 later (long story).

[Edited on 4/12/14 by kingster996]


coozer - 4/12/14 at 01:53 PM

I had to make a new nearside engine mount, holes in the block are a little bit different. Water pump runs the other way so as said an idler for the belt. I used the ac pump bracket to mount my alternator.

I've got plenty pics, giz a shout if you need anything.

From the off I used the zx9r carbs off the silvertop, and ran the vvt off the megajolt. 166bhp without any jetting up (which it needed).


The Knobs - 8/12/14 at 10:08 PM

Is this a worthwhile swap as I have a silvertop with carbs and megajolt?


kingster996 - 8/12/14 at 11:24 PM

It's debatable really.

The ST170 is a more developed engine with uprated rods, pistons and a better flowing head. So in theory you should get more out of it than the silvertop.

But the VVT throws a bit of a spanner in the works with an extra bit of electronics required to make the most out of it.

So you might be able to gain as much power per £ by doing some work on your existing engine.

One of the blokes on wscc has had good results with his carb'd ST and the vvt controller box, so it is very doable - but you might need to factor in some mapping time to get it right.

Personally, as I have both engines sat in my garage I'm using the silvertop to get my kit through IVA without a cat as it is already mapped and thus pretty much ready to go. Then next season I will probably put the ST170 in, but might look at some head work and see what can be done to up the power a bit (cams too perhaps). But that's a way off yet and it all could change!


The Knobs - 9/12/14 at 08:49 PM

Thought as much. Problem is my last Striker was a Rotrex charged 20v Yota with 272 bhp and without going down the sc route I think I will be disappointed. Built engines before that gained 15 to 20 bhp and tbh was not really worth the hastle. May just look out for a head and some cams on the second hand market or may have to wait til sc money is available.