hi, i have done a fair bit of research and now want to start to build a zetec turbo for my s2 only thing i dont know what engine to start with either the black top or silver top?? and cant find a definitive answer any one give me any pro's and con's on both engines??

also where is the best place to buy pistons and rods from? iv seen some on ebay anyone used them? and also noticed sizes vary from 84.8mm to 86mm . . .
standard bore size is 84.8 isnt it? so is it best to go 86mm and do a overbore as will be a second hand engine and will be slightly worn?

any help would be grateful, Nick

 

whats your budget? i'm currently building my zt using a st170 bottom end. there is a great guide by karlos g in the rst section.

 

iv just had a quick look . . . . so the pistons dnt need changing on the st170?? how much can they handle then? i would want at least 300bhp but closer to 350bhp that thread is def food for thought! my budget would of been 4k-5k maybe more but would just mean take a bit longer to do

 

As I said in my thread they will take 350bhp (Simon from Sitech told me this from extensive ST170 turbo development in case you wondered how I know! lol), so a target of 300-350bhp will be fine.

 

a good write up by the way . . . . how long you been running this?

 

Cheers!
Since the spring time, it's a daily driver and gets used hard, engine has been 100% spot on.

 

is there any machine work to be done for the zetec head to fit st bottom end? and will the cams still need changing sorry for all questions i just want weigh up all the options so i can commit to a certain way of doin it, cheers

 

with a healthy budget, just get a 2.0 blacktop, get some 86mm forged pistons and some steel rods, that's the first £1500 gone, then get uprated valve springs.
that is essentially a strong bottom end capable of 500bhp+, depending on many other factors of course.
that was my route and with a gt3071r strapped on with tubular manifold and various other things it puts good power out.

 

No it fits straight on, no the cams do not need changing.
You literally only need what is detailed in my thread mate, if it's not in there then I didn't have to do it! lol