Might cause detonation due to valve timing.
Will need to retard ignition timing to make up for it, which leads to less performance.
Plus, with cams you effectively lower the dynamic compression of the engine, which again leads to less performance.
So you'll want to run a lower HP shot, for safety.

I can't explain it 100% clear, because I'm not 100% clear on it.
But I got the basic idea.

Just remember, our engines are very, very sensetive to nitrous.

Hey Chris,
I am just seeing if we can get people that have done perfomance mods for the zetec (even if they post on focus sites) to post here. Besides, I didn't see anything listed on here about any such info. I already have a set of comp cams in my ride and found them to be VERY beneficial in making power. With my automatic they don't really get along, (wants to idle higher, feels like it wants to stall) but I am going to be swapping out for another combination in a few weeks. They definitely have a nice growl at cruise speeds though. I just wanted to say that I *JUST* swapped out my head for a 2000 focus piece (not ported, the ports looked a bit bigger on the 95' piece). It had the same lifter buckets in it as my production 95' head. Now I did have a 98' with the VCT on it apart and it had a different set of lifter buckets in it than my 95' head. Any clues? I know that when you pull the cams it is reccommended that you replace the lifters/buckets as well, Is there any specfic year that is better than the others?

go with "cat" cams i heard they are great for zetec's

Of course there is always a risk of detonation, that is why for every 50 hp of nitrous it is reccommended you retard ignition timing 1-2 degrees. If you run just a 50-75hp shot - you can usually use premium gasoline (93 or greater octane) to solve this for you. The few horsepower lost in retarding the timing these few degrees is well renumerated with the extra power being added.
...As for nitrous being dangerous on a ZETEC, yes it is if it is mis-installed or used incorrectly. I have quite the experience with this. The ZETEC 16V motor can use a properly installed DRY N.O.S. nitrous kit jetted for 50 hp.
...As long as the kit is installed properly, jetted sensibly!!, you use PREMIUM 93 or better octane gas and your fuel pump is in good working order(check fuel pressure) there is no reason for the ZETEC to fail when using nitrous.
...Nitrous should only be used for a MAXIMUM of 15 seconds at a time. These motors are not very sensitive to nitrous - just very sensitive to being misused. Give a gun to a kid without showing him how to PROPERLY use it safely and your asking for trouble. Same idea applies to nitrous use with the Zetec.

i have stage 2 cams and 50bhp wet nitrous kit and it works fine, it has been set up properly with a custom chip on a rolling road though. i checked with competition warehouse before i bought them and they said it would be fine.

i havent had it remapped since the supercharger has been fitted and havent driven it hard yet so will find out on friday how its doing.

when the chip was set up before, they set up the ignition timing and fuelling properly and said the way they had set it up i could use it turned on ALL the time if i wanted!

Actually the engines are very sensitive to nitrous,
any detonation and the pistons (among other things) will shatter like glass.
The Zetec has hypereutectic pistons, which are the worst pistons to run with nitrous.
Anybody with any automotive knowledge will tell you not to run nitrous (of any size or type kit) on an engine with hypereutectic pistons.
But if this is taken into account it can be tuned around.
I have run 55HP to 75HP shot for 3 years with no problems at all.
I have even run a 100HP & 125HP shot for a few runs at the track.

the zetec seems to break exhaust valves with poorly set up nitrous, but i have heard of of a couple of people melting a piston.

hi guys, im never in the forum, just came from meg!

anyways im looking to put some stage two cams in my car, i was thinking of comp cams but i can get stage 2 crowers for $175 or ford racing for $215 they are used cams, but just wanted to know if the comp cams go on with no problems would either of these two that im after fit??

I would go with the Ford Stage 2 over the Crower Stage 2.

thats what i was hoping to get but the guy hasnt got back to me, so it looks like its gonna be the crowers

anything i should know before buying them, like will they fit straight on? would i need to buy spring n retainers?i havent got a clue really!

I can speak of nitrous use from ACTUAL EXPERIENCE. I have run wet, dry and a multiport kit on my 2.0l zetec with jetting ranging over 150hp. Yes, I have broken LOTS of parts on my car. Yes, I have pushed the stock engine to it's limit (and over). YES, I know what the results are of nitrous injection on the stock ZETEC motor. To date I have rebuilt the engine in my car with STOCK HYPER-BLOW pistons FOUR TIMES. Yes they are garbage. But they can be used for mild performance upgrades. They are still better than using CAST pistons though. No, they DON'T shatter like glass. They usually melt, other times they get a bit soft and sag a bit in the middle. Sometimes taking the exhaust valves. I have a box of melted items if anyone wants some pictures. The only kit I found that worked RELIABLY was the N.O.S. dry nitrous kit for the Focus jetted for 50hp . A multiport setup would be the best, but they don't offer a multiport kit for the ZETEC (I put together my own). The intake manifold on the zetec will not allow a wet kit to be used safely . It allows the gas injected with the nitrous to puddle in the gooseneck in the manifold. This allows the engine to run lean (lots of melted parts). Almost every time my car melted items in the engine, I was asking for it.

I have been using nitrous for about 3 years on my Zetec.
I have jetted 100/125HP with no problems. (Though I prefer the 55-75 HP range.)
Never broke or blown a single thing, never even backfired.
Its all in the tune and having a little knowledge.

I recommend against nitrous for the average person because rebuilding the engine is beyond their skill/desire, and buying and installing a new engine is beyond their budget/skill/desire.

I read books, asked some long time racers, and generally got as much info on the subject as I could to make an informed choice.
And I want to make sure that other people on this board do the same as well.
To many people talk without knowing, or having done.

The pistons will shatter from a backfire which would be from running rich, they melted from running lean.
There really is little room for error on these engines when dealing with nitrous.
But if you stay in the "sweat spot" they respond very well.

I agree a wet kit on a zetec borders on stupid.
But any dry kit will work very much the same.
I prefer Zex beacuse it monitors bottle pressure vs fuel pressure, and it uses the TPS voltage instead of a micro-switch.

Okay this is not helping (me personally) because I have read conflicting reports on dry vs wet kit on a zetec.

I know I've posted this before in a couple threads.

But the two of you say a wet kit on a zetec is not a smart idea...however on FJ a couple of guys have stated that a dry kit on a zetec is asking for a blown engine (also because of running too lean)...so wtf. You guys both have your dislikes of a certain kit but for the same damn reason.

Pre 98 Contours have a return fuel system,
Foci, Cougars, and Post 98 Contours have a returnless.
Return style allows the flexibility of uping the fuel pressure and adjusting the fuel pressure pulse to supply more fuel.
Returnless have much less room in both departments.

I would still go with a dry kit.
Returnless will be fine with a 50HP shot,
(I haven't done the math to figure out amx HP shot),
anything larger and I would upgrade to a bit larger injectors.

Asking questions here is a good thing, but nobody here is the god of nitrous.
I would reccomend reading "Sport Compact Nitrous Injection".
(There are better books, but this is a good general overview.)
This will give you alot of no-nonsense answer to questions, show you some of the science and math behind nitrous, and generally allow YOU to make an informed decision for YOUR car.

Conflicting expereinces is one reason why nitrous has a bad reputation.

I simply stated that I have rebuilt the stock engine 4 times as a show of how much TIME and MONEY I have spent RESEARCHING the best type of nitrous kit for the stock motor and where it's limitations are. Have you done such?
... I tested wet kits to start with and found that they are a complete waste of time on the 16v zetec. The intake manifold allows the air/fuel mixture to puddle in it causing a lean condition and allowing the engine to detonate. (verified via wideband O2 sensor) The only way to use a wet kit on the 16v zetec would be to design a new intake manifold that did not have the gooseneck in it. (I have done this)
...The only sort of nitrous kit that can be safely used is either a dry kit that tickles the stock injectors to inject more fuel or to setup your own direct port system that injects fuel AFTER the gooseneck. Either case requires that you have ample fuel supply and the kit be properly installed per the manufacturers directions.
...Injecting nitrous without extra fuel WILL destroy your engine. Please insure you use a kit that will provide additional fuel.

Originally posted by evocontour:

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I simply stated that I have rebuilt the stock engine 4 times as a show of how much TIME and MONEY I have spent RESEARCHING the best type of nitrous kit for the stock motor and where it's limitations are. Have you done such?

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As stated;
I learned about the engine, learned about nitrous, read other people experiences, and asked questions of people who have alot of expereince racing cars and building engines.
Therefore I haven't broke anything and have yet to need to rebuild the engine.
Do it right the 1st time is my motto.

And considering that I was able to chop just under 2 seconds (1.9 to be exact, 16.3s to 14.4s) off my 1/4 mile time with only a 65HP shot of nitrous (time slip was posted and had witnesses when I did it) I would say that I am most likely the most succesful users of nitrous on a Contour and on a Zetec engine.