KW-rscos Posted January 31, 2013 Share Posted January 31, 2013 Hi All, I have decided to bit the bullet and go Zetec turbo in my GTi, the aim is for around 350bhp.I am hoping to use a 2.0 Silvertop as I already have the engine and it bolts straight into my engine bay.I have purchased Eagle Rods and Supertech Pistons from the states, which should give a compression ratio of 8.7:1. I have a HO EFi inlet manifolt, but I have deigned a billet fuel rail. I am looking to run an Omex 600 ecu. So is this a realistic basic spec? What injectors can/should I use? Will I need any head work? Will I need new cams? Will I be ok with the hydraulic lifters? Will the crank take that sort of power? What head gasket should I use? What else have I missed? Regards, Kieren. Link to comment Share on other sites More sharing options...
Stu Posted January 31, 2013 Share Posted January 31, 2013 Hello Kieren Did you buy those rods and pistons for any particular reason? If you do somehow manage to end up as low as 8.7:1, you will struggle on pump fuel to get to your target power of 350bhp. I wouldn't want to go above 8:1, preferably a few tenths down. Be careful with the OEM injector holder as it leaks where it bolts into the inlet manifold. Not sure if your replacement idea will resolve that. You'll want injectors around 500cc/min for that power. I would open up the exhaust ports a bit for that power. Standard 2L cams will be fine. Run a 1.8 or 1.6 exhaust cam if you want a bit more response. Hydraulic followers will be fine if you go for a double valve spring conversion. Single uprated valve springs (eg Pipers) will start to float before your target power. Crank is fine at 500bhp+ I'd use an ST170 head gasket as it's the thickest multi-layer steel one available for the zetec engine. Missed? Turbo, manifold, clutch, gearbox, etc People often underestimate just how much is involved in this kind of conversion... Link to comment Share on other sites More sharing options...
KW-rscos Posted January 31, 2013 Author Share Posted January 31, 2013 Hello Kieren Did you buy those rods and pistons for any particular reason? If you do somehow manage to end up as low as 8.7:1, you will struggle on pump fuel to get to your target power of 350bhp. I wouldn't want to go above 8:1, preferably a few tenths down. Be careful with the OEM injector holder as it leaks where it bolts into the inlet manifold. Not sure if your replacement idea will resolve that. You'll want injectors around 500cc/min for that power. I would open up the exhaust ports a bit for that power. Standard 2L cams will be fine. Run a 1.8 or 1.6 exhaust cam if you want a bit more response. Hydraulic followers will be fine if you go for a double valve spring conversion. Single uprated valve springs (eg Pipers) will start to float before your target power. Crank is fine at 500bhp+ I'd use an ST170 head gasket as it's the thickest multi-layer steel one available for the zetec engine. Missed? Turbo, manifold, clutch, gearbox, etc People often underestimate just how much is involved in this kind of conversion... Excellent, Thank you Stu. I understand there is a lot of things to do, but just wanted to get a bigger picture of what else I need. I bought the pistons as I have seen so many people online saying how weak the originals are above 200-250 bhp. my head has already been skimmed once a couple of years back for a HG failure, so I guess the best thing to do when I have the engine out is to measure the compression ratio. With the injectors/fuel rail, I am looking to run end feed with my billet fuel rail, however do they leak because people use the original "bucket" shim things? if so I can design something around that. I have a T34 turbo, but cant remember the sizes off the top of my head. I am looking to use a focus RS tubular manifold and getting the correct flange welded on.unsure of clutch/gearbox yet, however I'm thinging RS2000 mtx75 with an ap clutch? Thank you for the advice. Regards, Kieren. Link to comment Share on other sites More sharing options...
Stu Posted January 31, 2013 Share Posted January 31, 2013 Yeah, I think we're talking about the same shims. To be honest I would just run the plastic inlet manifold from the Focus (or Focus RS if you really want, it's the same apart fom the TB). The Mondeo TB is a good match. I know someone else running this package at about 350bhp. Easier than dicking around with the side-fed stuff really. Std Focus exhaust manifold is sort of tubular by design? And can be picked up for not much cash.. If you're going to modify it anyway, why spend more than you need to? AP RS clutch? It fits some MTX75's but not others. There is a Sachs clutch which doesn't foul the internal diff housing. Using a proper Focus RS MTX75 would work, but requires custom mounts I believe. Link to comment Share on other sites More sharing options...
KW-rscos Posted January 31, 2013 Author Share Posted January 31, 2013 Will the Focus RS inlet manifold flow enough for this type of power? The standard focus 2.0 Exhaust manifold is kind of tubular by design, and I could put the T3 flange on it, but will it flow enough? and would it match up to the silvertop head being for a blacktop engine?What sort of power will the sachs unit take? I am ok sorting the mounts out so the focus RS box might do the trick, however I will need new driveshafts. Regards, Kieren. Link to comment Share on other sites More sharing options...
Stu Posted January 31, 2013 Share Posted January 31, 2013 Yes, the Focus inlet manifold will be fine for 350bhp (I think the N/A and RS ones are the same, apart from TB- don't pay over the odds for an 'RS' one). I'd be very surprised if the n/a focus exhaust manifold didn't do the job - when you consider an escort rs turbo manifold has been dyno proven at 355bhp! It'd be fine on a silver top.. Not sure on the limit of the Sachs clutch, but I know of one on a 350bhp car.. Link to comment Share on other sites More sharing options...
KW-rscos Posted January 31, 2013 Author Share Posted January 31, 2013 The Focus inlet, is it end feed injectors? would the EFi one I already have flow better or worse? Regards, Kieren Link to comment Share on other sites More sharing options...
Stu Posted January 31, 2013 Share Posted January 31, 2013 Focus is end-fed. I've not seen flow bench numbers for either manifold so couldn't say for sure. All I can tell you is what i've seen on the dyno and both manifolds will do 350bhp. Link to comment Share on other sites More sharing options...
KW-rscos Posted January 31, 2013 Author Share Posted January 31, 2013 Excellent, Thank you for the info. Regards, Kieren Link to comment Share on other sites More sharing options...
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