want to change cams in my 96 se how hard is it really to change them out can I do it with the engine still in the car and what all am I going to need to have if someone can make a list or something for me because I am sure other people want to know also

Robbie

Yeah, I also want to know. I've heard that earlier 240sx and altima cams can be fitted in also, but that that you had to drilll out a dowel pin or something. What earlier cams can be retro fitted with no modification?

http://www.pdm-racing.com/products/cam_corner.html

I would like more info too. According to the pdm-racing website these cams will cost $453 + shipping and generate about 10 hp gain.

Only problem is I've never opened up an an engine or measured valve to shim clearance before.

So I guess the first thing we need to figure out is what kind of tool or guide you use to do this.

It's probably not even difficult if you are somewhat mechanically inclined and very patient and careful....But what the F$#k do I know???

Anyone?? Anyone?

i wanna know

numatik wrote:Yeah, I also want to know. I've heard that earlier 240sx and altima cams can be fitted in also, but that that you had to drilll out a dowel pin or something. What earlier cams can be retro fitted with no modification?

The Dowel Pin reference is made to using two exhaust cams from a 91 240sx. You repin the one you will use on the intake so that it lines up correctly for the valve opening and closing events occur at the right time.

Forget about the Altima Cams. That is only a rumor to use them as an upgrade.

As far as measuring clearance, you will need the new cam and a feeler gauge. It's not a real easy process on the DOHC KA as there are no actual adjustments. you have to replace the shims accordingly. And you will need to measure the old shims as they may be worn and and not exactly the spec it says on it. You will need to do this with the new cams in place. And chances are it won't be a very quick process unless you find a dealer that has all the shims you need in stock.

As far as colt cams, they are regrinds so they make custom cams for you. You have to measure what you have and they will send you custom shims for it...

Im happy with the nissmo cams. they are new out of the box never grinded. but the one I run on my exaust side is real tall!

technoman wrote:Im happy with the nissmo cams. they are new out of the box never grinded. but the one I run on my exaust side is real tall!

Did you do the work yourself?

How much did it cost (parts and labor)?

How difficult is the labor?

As far as colt cams, they are regrinds so they make custom cams for you. You have to measure what you have and they will send you custom shims for it... [/QUOTE]

Assuming you go the colt cams route...

How hard is the labor to perform?

Thanks!

The cams cost 250 from the dealer i worked at (discount)I installed them after i got the exaust cam regrounded to a higherlift a duration.It took about two hours very easy to install. these cams are exactly what a stock KA motor needs. i think this mod should be the first mod anyone does to their KA. The stock 232 degree cams REALLY suck!

Its always a good idea to change out your rocker arms when you install a new camshaft. My R4 Nismo cam cost $300, but the rocker arms i paid $360 at the friggin dealership! Little did i know i could find them for almost $200 less online! My SOHC was very very easy to change the cam, DOHC shouldnt be too much harder.1) Pull your valve pan cover off (i found pulling my spark plugs helpd a lot in case i needed to turn the engine over, i had no compression to fight with)2) mark your timing chain to cam sprocket(s) with paint so you can realign it3)unbolt your cam sprocket(s). They will be tough to remove. I had a friend with a socket on the crank pulley to keep the assembly from rotating while i broke them loose (BE CAREFULL!!). Support your timing chain with a coat hanger from the hood latch (or similar, if you drop it, you will have to dissamble the front cover to fish the chain out of the oil pan)4) Gradually loosen your rocker arm shaft bolts (i believe its from middle to both ends) until you can remove the entire assembly. The camshaft retainer bearings should come right off, then the camshaft.5) Lube up your new cam(s) with white lithium based grease. If you are replacing your rocker arms (i suggest it), mark the location of the old ones as you take them off, just in case you need to replace your factory cam, you can then re-use your original rocker arms.6) reinstall everything in reverse order. I had to manually push in the timing chain tensioner so i could get the sprocket with chain onto the camshaft. Be sure your paint marks match up, or your cam timing will be off (by at least 10 degrees per tooth, which isnt good)7) you will probably have to manually set your timing, depending on how radical the cam was that u just installed. My Nismo cam runs soo rough, and before i got the HKS Super AFR, i wouldnt even hold an idle. But cams are the best power per dollar upgrade i think you can do to your NA 240SX.8) Keep on rocking!! :ylsuper

Thanks for all the detail. I hope the shims on the dual cam motor don't make it too much of a pain in the a**.

Where did you order your nismo cams from.

And where did you buy the shift kit and exhaust from.

My exhaust needs to be replaced right away, so I'm trying to find a good price on a apexi or hks or 5zigen cat-back for an S14.

THANKS

I got my Nismo cam (remember SOHC, they dont have a DOHC) from http://nismoparts.safeshopper.com/index.htm?258My HKS Sport exhaust was $450 from http://www.nopionline.com/My C's short shifter was around $250 (about 4 years ago) and was also from NOPI, but they dont carry it anymore. However, check http://www.jspec.com/csshifter.html to get it from JSPEC.Now my HKS sport exhaust is different than the others that you are looking at. It is barely louder than stock, dual 65mm tips, premuffler and muffler. Its very very high quality tho, silver satin finish, mandrel bends, chrome intercooled tips, real nice in my opinion. Im not much for the huge coffee can type exhausts like 5Zigen or the Apex N1, but NOPI sells the N1 for $452.67.:rockon

OK The Apexi are one piece and I can't afford the shipping.

I can get 65 millimeter HKS high power for about 485 shipped or a 5 Zigen Fireball 60 Millimeter for 500 shipped, which one should I get?

I guess they aren't full stainless, but I'm too poor to worry about that right now.

I'm leaning towards HKS, because I haven't heard too much about 5Zigen, but if anyone has any input I'd appreciate it

Thanks

They do sell 95 and later cams set for 360

http://nismoparts.safeshopper.com/index.htm?258

these cam rule and should be the first mod anyone does.

I assume that this doesn't include shims.

Where do you buy them from.

Can you order them from a regular auto parts store or are they Nissan only, or what?

If you get nissmo cams you will not need shims. I run a even taller cam on my exhaust side and im still using stock shims.

technoman

did you lose any low end when you changed cams?

thanks

technoman wrote:...i got the exaust cam regrounded to a higherlift a duration....

Just curious what exactly does it mean if the exhaust cam is very tall.

And why did you have it reground to a higher lift duration. What does this mean, and what did it do for your cars performance.

Sorry if these seem like stupid questions to you, but I am very serious about doing this upgrade now.

What do duration and lift mean?

Do I need any computer upgrades to replace these?

And will my car still pass emissions?

The fact that I don't have to worry about shims makes putting another $360 on the discover seem like a great idea.

Thanks alot!

Shea

technoman

Did you also change the rocker arms?

I'm hoping that this is just a precaution that isn't really necessary!

Thanks

You will want to change your rocker arms. Your OE ones have broken with your OE cam. If you reuse your OE arms with a new custom cam, it will more than likely score your new cam giving u all kinds of problems.

Lift is how high the valve is opened. For the SOHC this is .408" i believe. My Nismo cam lowered this slightly to .402" lift. Duration is how many degress of camshaft rotation the valve is opened. Again, SOHC was 228 degrees opened, now my Nismo is 270 degrees (a HUGE difference which required a lot of work to get it to idle).You should be OK with your stock ECU, but if your cam is too wild, you may not idle. If this is the case, do like i did and get an HKS Super AFR that will control your idle. Im waiting until im DONE with my engine mods before i change the ECU, since its not just a chip, but rather a whole reworking of the ECU.As far as emissions, unless they cam you are getting is CARB exempt, i doubt it. You will pass visual (they cant see the damn thing), but i doubt u will pass sniffer. I live in Louisiana and we dont give a rats @$$ about our air here (or anything else for that matter :thinker ), so your state may be different.

"You will pass visual (they cant see the damn thing), but i doubt u will pass sniffer. "

Maybe I will just put 3 bottles of dry gas and fill up the tank.

And then take it out on the highway at about 97 miles an hour in forth for twenty minutes or so, right before the emissions.

I hear thats a good way to get an old beater to pass the sniffer.

I hope it still holds an idle with the nismo cam, I'd rather not have to drop the cash on an HKS super AFR.

Anyone know part #s for the S14 Rocker arms?

And where to get em for cheap?

I'm guessing http://www.nissanparts.cc

is the best place to get 'em , but I duknow.

Thanks

Do aftermarket companies make S14 rocker arms or should I just buy the factory ones?

Ok for starters no S14 has rocker arms. The cam lobe pushes down on the valve directly. When you remove you valve cover the first thing you see are the cams. You must mark your chain with white paint and you must remove you cam towers thats it. their are no rocker arms in the twin cam KA motor. and yes with the nissmo cams you will feel more power from 3,000 to 6,000 Im not telling what size cam i use on my exaust. i keep that to my self.DON'T MISS AND MATCH YOUR NISSMO CAMS. MAKE SURE YOU PUT THE INTAKE ON THE INTAKE SIDE. YOU WILL HAVE A MAJOR PROBLEM IF YOU MIX THEM UP.

I'm at work on a saturday so I have WAY too much time on my hands here is detailed of camshaft time

We begin with the piston all the way at the top with both valves closed. Just a few degrees ago the spark plug fired and the explosion and the expansion of the gasses is forcing the piston towards the bottom of the cylinder. This is the event that actually pushes the crankshaft around to create the power and is referred to as the "power stroke". Each "stroke" lasts one half crankshaft revolution or 180 crankshaft degrees. Since the camshaft turns at half of the speed of the crank, the power stroke only sees one fourth of a turn of the cam, or 90 camshaft degrees.

As we move closer to the bottom of the cylinder, a little before the piston reaches the bottom, the exhaust valve begins to open. By this time most of the charge has been burned and the cylinder pressure will begin to push this burnt mixture out into the exhaust port. After the piston passes the true bottom or Bottom Dead Center, it begins to rise back to the top. Now we have begun the exhaust stroke, another 180° in the cycle. This forces the remainder of the mixture out of the chamber to make room for a fresh, clean charge of air-fuel mixture. While the piston is moving toward the top of the cylinder, the exhaust valve quickly opens, goes through maximum lift and begins to close.

Now something quite unique begins to take place. Just before the piston reaches the top, the intake valve begins to open and the exhaust valve is not yet fully closed. This doesn't sound right, does it? Let's try to figure out what is happening.

The exhaust stroke of the piston has pushed out just about all of the spent charge and as the piston approaches the top and the intake valve begins to open slowly, there begins a siphon or "scavenge" effect in the chamber. The rush of the gases out into the exhaust port will draw in the start of the intake charge. This is how the engine flushes out all of the used charge. Even some of the new gases escape into the exhaust. Once the piston passes through Top Dead Center and starts back down, the intake charge is being pulled in quickly so the exhaust valve must close at precisely the right point after the top to keep any burnt gas from reentering. This area around Top Dead Center with both valves open is referred to as "overlap". This is one of the most critical moments in the running cycle, and all points must be positioned correctly with the Top Dead Center of the piston. We'll look at this much more closely later.

We have now passed through overlap. The exhaust valve has closed just after the piston started down and the intake valve is opening very quickly. This is called the intake stroke, where the engine "breathes" and fills itself with another charge of fresh air/fuel mixture. The intake valve reaches its maximum lift at some defined point (usually about 106 degrees) after top dead center. This is called the intake centerline, which refers to where the cam has been installed in the engine in relation to the crankshaft. This is commonly called "degreeing".

The piston again goes all the way to the bottom and as it starts up, the intake valve is rushing towards the seat. The closing point of the intake valve will determine where the cylinder actually begins to build pressure, as we are now into the compression stroke. When the mixture has all been taken in and the valves are both closed, the piston begins to compress the mixture. This is where the engine can really build some power. Then, just prior to the top, the spark plug fires and we are ready to start all over again.

The engine cycle we have just observed is typical of all four- stroke engines. There are several things we have not discussed, such as lift, duration, opening and closing points, overlap, intake centerline and lobe separation angle.

Most cams are rated by duration at some defined lift point. As slow as the valve opens and closes at the very beginning and end of its cycle, it would be impossible to find exactly where it begins to move. The rated duration is at .006" tappet lift. In our plot, we use valve lift so we must multiply by the rocker arm ratio to find this lift. For example, .006" x 1.5 =.009". Instead of the original .006" tappet lift, we now use .009" valve lift. These opening and closing points are circled so that you can see them. If you count the number of degrees between these points you will arrive at the advertised duration, in this case 270 degrees of crank- shaft rotation. Some cam manufacturers rate their cams at .050" lift. If we again multiply this by the rocker arm ratio, we get .075". we can mark the diagram and read the duration at .050" lift. The lift is very simple to determine. You can simply read it from the axis going up. This is the lift at the valve as we said earlier. Sometimes you will hear lift referred to as "lobe lift". This means the lift at the lobe or the valve lift divided by the rocker arm ratio. In this case, it would be .470" divided by 1.5 or .313" lobe lift. The lift is simply a straightforward measurement of the rise of the valve or lifter.

We touched on opening and closing points a little earlier, but now we want to consider them even further. We talked about when these points occur, and how they are measured. The valve begins to move very slowly then picks up speed as it approaches the top. It does the same closing, coming down quickly then slowing to a gentle stop. It's kind of like driving your car. If you were to go from 0 to 60 mph in a fraction of a second and stop instantly, you can imagine what that would do to the car, not to mention the driver. It would be much too severe for any valve train to endure. You would bend pushrods, wear out cams, break springs and rockers, and lose all dynamic design. The cam would not run to the desired RPM level as you would have all these parts running into each other. As the valve approaches the seat, you also have to slow it down to keep the valve train from making any loud noises. If you slam the valve down onto the seat, you can expect some severe noise and a lot of worn and broken parts. So it is easy to see that you can only accelerate the valve a certain amount before you get into trouble. Looking a bit further at the timing points, the first one we see on the diagram is the exhaust opening point. We have all noticed the different sounds of performance cams, with the distinct lopes or rough idle. This occurs when the exhaust valve opens earlier and lets the sound of combustion go out into the exhaust pipes. It may actually still be burning a little when it passes out of the engine, so this can be a very pronounced sound.

This begins the overlap phase, which is very critical to vacuum, throttle response, emissions and especially, gas mileage. The amount of overlap, or the area between the intake opening and the exhaust closing, and where it occurs, is one of the most critical points in the engine cycle. If the intake valve opens too early, it will push the new charge into the intake manifold. If it occurs too late, it will lean out the cylinder and greatly hinder the performance of the engine. If the exhaust valve closes too early it will trap some of the spent gases in the combustion chamber, and if it closes too late it will over-scavenge the chamber; taking out too much of the charge, again creating an artificially lean condition. If the overlap phase occurs too early, it will create an overly rich condition in the exhaust port, severely hurting the gas mileage. So, as you can see, everything about overlap is critical to the performance of the engine.

The last point in the cycle is the intake closing. This occurs slightly after Bottom Dead Center, and the quicker it closes, the more cylinder pressure the engine will develop. You have to be very careful, however, to make sure that you hold the valve open long enough to properly fill the chamber, but close it soon enough to yield maxi mum cylinder pressure. This is a very tricky point in the cycle of the camshaft.

The last thing we will discuss is the difference between intake centerline and lobe separation angle. These two terms are often confused. Even though they have very similar names, they are very different and control different events in the engine. Lobe separation angle is simply what it says. It is the number of degrees separating the peak lift point of the exhaust lobe and the peak point of the intake lobe. This is sometimes referred to as the "lobe center" of the cam, but we prefer to call it the lobe separation angle. This can only be changed when the cam is ground. It makes no difference how you degree the cam in the engine, the lobe separation angle is ground into the cam. The intake centerline, on the other hand, is the position of the centerline, or peak lift point, of the intake lobe in relation to top dead center of the piston. This can be changed by "degreeing" the cam into the engine. We show it installed in the engine 4° advanced, or at 106° intake centerline. This is usually considered as a way to increase bottom end power, but as you can see there is much of the charge pushed out the exhaust, making a less efficient engine.

well put grygst76.......

go to http://www.howstuffworks.com and type in camshafts and watch the animation. it perfectly illustrates and explains how they work.

Nick.

[quote=" sheadee240

Anyone know part #s for the S14 Rocker arms?

And where to get em for cheap?

I'm guessing http://www.nissanparts.cc

is the best place to get 'em , but I duknow.

Thanks [/quote]

DOHC KAs don't use rocker arms, they are direct actuating. You will most likely need a few shims, most people don't spec out each shim, or just skip it altogether, but 99% of the time at least 6 of them are out of spec. The whole job is very easy is you're mechanically inclined, and KNOW how an engine works. I'm heard horror stories of people who attempt a cam swap, and drop the chain or move it a few teeth. If you're unsure, don't try it. Piston/valve contact is not pretty.