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Old 01-08-2008, 09:39 PM   #1
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Exclamation So you're planning on going FI

So you've decided to go turbo.... NOW WHAT???

You need to decide on what you power goals are then you can start planning from there. You need to start with the most basic of decisions... stock motor or built?


The biggest advantage of using a stock motor is COST, but going the cheap route is going to limit the amount of power you can make.

On a NON-SVT engine (Zetec and Duratec) you can run around 12psi before you start getting into the "breaking" zone.... as in where you start breaking rods.The Zetec and Duratecs both use powdered rods and they are THE weak link in your motor.

SVT's... You guys are the lucky one's when it comes to boost. SVT had the foresight to use sinter forged MAHLE rods in your motors which give you a BIG advantage when it comes to boost. The weak link in the SVT motor is its pistons. You can easily run 17psi on an SVT motor... personally I ran 19psi for 2 years before getting power hungry and .... well needing a new engine.


For the serious driver a built engine is a must.. but there are several different levels of building.


The cheapest and most popular is to just swap out the stock rods and pistons for forged aftermarket ones. BOTH Zetec/SVT/and Duratec have to swap out rods and pistons when upgrading.... yes even though the SVT has forged rods they too have to be swapped since no one makes an aftermarket piston that works with the SVT rod.


The standard SVT/Zetec block should be good to somewhere over 20psi, there have been many people do this on the stock stuff. The only difference between the Zetec and the SVT blocks are oil squirters (SVT) that blow oil onto the bottoms of the pistons to help cool and lubricate them... are they needed... not really but they are nice to have.

If you have an extra $1500 laying around and if you can find one Montune makes a CGI Zetec block which are rated for 32psi of boost. CGI means carbon graphite impregnated... the same stuff the PowerStroke blocks are made of... An EXCELLENT choice for big boost.


Well the SVT guys came out ahead here too, the STOCK SVT head/cams are excellent for boost.. and its a good thing since there really is NO aftermarket support in this area in the United States. You can get a good Port & Polish and bigger valves but no one makes a direct swap without going out of country.

Zetec's.. you guys have several choices on cams (which I'm not going into) and you guys get the FordRacing head that already comes ported with bigger intake valves in it. Of course you can still get a P&P and do valve work to it as well... but its pretty damn good out of the box.

When choosing cams you should look for "boost specific" cams, there is a difference. When building a motor for FI your cams should not have alot of overlap. when you get too much overlap you basically end up blowing your boost out of the exhaust. On the bright side you can install cam gears and dial out some of the overlap if you already have "larger NA cams"


There are not many choices out there, the SVT guys are pretty screwed. Unless you make an intake, you are stuck with the DSI. I say stuck for the basic reason of the DSI flows like crap... thats why i dont have one.

Zetec's have a couple of choices, an early 2000 intake, the FordRacing intake, or make one. Even though the STOCK manifold isnt bad.

Now before you run out and start hacking on pipe trying to make a manifold you seriously need to go read about flow dyanamics, design, runner length, plemium volume and get an understanding of what needs to be designed into the intake... just throwing one together can greatly decrease you power... no matter how COOL it looks.


No one makes one... why you just dont need it. Tom is the only one I know of that has broken a crank... at 720whp.


A lightend flywheel is a GREAT addition to any Forced Induction motor, they let the engine rev extremely quick (compareed to stock) the only downside I see from a light weight flywheel is they tend to rattle a little, but its worth it.

I also recommend an upgraded clutch, if you dont do it now.. you WILL do it later. Theres just no way around it. A stock SVT clutch will let go around 250wtq and the MTX 75 is less than that. I suggest at least a stage 3 clutch for the MINIMUM clutch to use.


I'll be upfront, you guys are definitly limited by your transmissions. BUT there is still hope!!! Lentech makes a wide variety of stuff for the Focus ATX and if you want more than 220whp or so then you need to go to their website and look around.


The single best thing you can do (and pretty much the only thing needed) is install a LSD.. Limited Slip Differential. An LSD it what lets you get the power to the ground, without it you're just going to spin one wheel... and thats some embarrising shit. The LSD will also help you with daily driving .. they are great for handling in curves and greatly help in the rain.

The 2 REAL choices are Quaife and Torson.... what about OBX did you say??? Not even in my lawn mower... I wont even discuss that... go find a Honda forum.



Regaurdless of your power goal 42# injectors are the minimum that I would even consider using... they are just a few bucks more than smaller ones and can save your motor.

ALWAYS use a properly sized injector... too big is fine, too small is dangerous.


I would not recommend anything less than the '03 upgraded fuel pump, the older pumps just dont flow as well.

Using a stock fuel pump and fuel rail you can manage around 250whp safely on both Zetec and SVT. With a BOOST A PUMP you can get quite a bit more out of the Zetec closer to 300whp... providing proper tuning.

On the SVT with a BAP and proper tuning (that I figured out) you can achieve well over 350whp on the STOCK fuel system. I have datalogs showing 62psi of fuel pressure at 7200rpms while running 20psi. I shared this info with Tom and he is also doing the tune adjustments on the tunes he does.

Return style fuel system.. When you cant get enough fuel using the returnless system the only alternative is going to a custom return style system, just like on a diesel. Right now there are no kits, so you pretty much have to build your own from scratch... when ever we get a good write up on it I'll copy/paste it to this thread.

That pretty much covers the engine and tranny basics of boosting... next we will discuss choosing you form of FI.

[B]1951 McCormick FARMALL M
2007 MINI Cooper S Turbo... new project car
1998 Chevy 3500 Ext cab, long bed, 4x4, duelly, turbo diesel
2004 Harley V-Rod.... sex on wheels
2011 Harley Electra Glide Ultra Limited

Last edited by 03OrangeSVT; 01-09-2008 at 12:56 AM.
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