416EX kit?

[Sleeping Catfish]

I have a few questions for anyone who has one or knows about them. How much does it increase you acceleration? How much does it cost installed and everything? What is your top speed? Will it beat a Raptor? It is good for woods racing? I heard it was for top speed but would just like to hear what you guys say about it. Oh yeah, and how reliable is it?

A 416 is not a kit it is just a bigger piston. If you replace your cam at the same time as your piston you will notice an improvement in acceleration and throttle responsivness. I recommend the XR400 cam as it is a factory part and doesn't require you to resurface your rockers. I have had mine in since spring and have had no problems whatsoever even riding at Little Sahara in 110 degree heat.
Norm

piston and gasket $134 from marcums
xrcam $120 marcums
labor about 2 or 3 hours

acceleration don't know,,,faster than stock, yes. Should run with a raptor,,if not you won't get your doors blown off or anything. Top speed don't know,,,never get my bike in 5th gear,,,if you wreck wide open in 5th,,you'll probably die,,so that's pretty fast I'd say. Lot's of pull through all gears,,,just get it and you'll be able to answer all your questions. You'll like it,,,,promise..

...but if you wreck in 4th, you'll only be mostly dead...
:huh

does a bigger sleeve come with the kit ?

No sir,,,just piston, clips, rings, and gasket kit if ya get it from marcums. And you won't need another sleeve,,you'll need to get the sleeve in your motor now bored 80 over,,or just take the cylinder to get it bored,,probably around 40 bucks at most respectable machine shops..

[Honda Guy]

So your looking at about $300 for everythigng including a XR400 cam? How far over a a 416? How much faster is a 440? Is a 416 as relible as stock?

[kabd69667]

a 416 is not as reliable as stock, but it is more reliable than a 440. They say that the 416 revs faster than the 440

[ChadEXer]

Hey Rico, I got the 416 kit from Marcums like you advised me to. Do you think I need to get the valves and springs and stuff. How much of a difference will it make?

[kabd69667]

Valve springs for an xr cam? No don't waste your money on them untill you get a more agressive cam

[ChadEXer]

What about porting and polishing. My mechanic gave me a 400 head he had sitting in his shop that was in perfect condition and I was going to take it tommorrow and get it ported and polished for $100. Do I need to do this? How much of a difference will it make? I have a Yoshi full system if that makes a difference.

[chris29]

You don't need your head ported and polished but it does make a really big differance. It will increase the air flow and make the 416 come alive.

[ChadEXer]

Thanks chris29. Im going to go have it done tommorrow. Then all I will like is having it all put in.

[kabd69667]

WAIT! is your carb modified? Do you have an aftermarket carb? If you answer no to both of these questions, your wasting your money on porting.

[ChadEXer]

No its not right now but I will be getting a FCR very soon. So I will just go ahead and do the porting while the motor is apart

[Honda Guy]

Is Marcums a good company they have a JK 416 kit for $155 including BORING would yall trust them to bore your engines? Can u really mess up when boring?

[Dave400ex]

I haven`t heard one bad thing about Marcum`s. I think you can trust them.

Originally posted by Honda Guy
Is Marcums a good company they have a JK 416 kit for $155 including BORING would yall trust them to bore your engines? Can u really mess up when boring?

Marcums is the only place i do business with anymore and I'd trust Terry to do just about anything,,if you do choose to go with marcums,,get the xrcam and viton valve seals also,,might cost ya another $150,,but well worth it.. I highly recommend marcums to anyone interested in parts or service..

Originally posted by chris29
You don't need your head ported and polished but it does make a really big differance. It will increase the air flow and make the 416 come alive.

with an aftermarket carb only,,,you'll notice a .04 increase in power maybe with it ported running a stock carb,,which for $100 will probably be just a play/mild port,,it won't hurt but you'll feel no power increase. If your gonna get a carb down the line then it will be money well spent.

If your carb lets in 50 gallons of air a minute and your head lets in 75 gallons of air per minute,,your already not meeting the needs of the stock head ports so why let your head allow 90 gallons of air after being ported, when the carb is still only letting in 50 gallons????

[Scott]

And Rico says to get the SpeedRacing Muscle too!




I think he's payrolled by Speed and Marcums...:D :D :D :D

Just kidding Rico. I think I want to be bankrolled by Marcums and SpeedRacing too...

Well I know I don't wanna throw money away to a company with a 100% mark up and one that also only talks with customers that have a checkbook or credit card in hand. Marcums takes care of his customers and gives freindly advise,,I've spent the last 3 years buyin and dealin with companies and want to share what I've learned over that time with others that are just now getting into the ATV sport and still have there blinders on,,you know not seein the big picture...I guess I'm a dumbarse for tryin to help people and give good advise from hands on experience..

[Scott]

WHoa, relax Rico. I was only kidding. I get a kick out of people asking you the same questions over and over and over and over..... I think you get the picture.

After a couple dozen posts, I think most regulars on here know that you are very fond of the 416 kit, and from the sounds of things, justifiably so. You've also had very good luck with Terry Marcum, and the people you've referred to him (Chad in TX for example) come back and post the same thing.

I wasn't trying to harass you, I has just kinda poking fun at the multiple posts asking the same thing, that then get the same resonses automatically.

Maybe we should ask Leo to put a couple of these in the FAQ's. Like Is a 416 kit good? Yes, and the cheapest place to get it sounds like Marcums. Is a steering stabilizer good? Yes, and get a rebuildable one like the Muscle, Denton, new Pep, etc. What tires should I use? What pipe should I use? Who should I have build my engine?

Or we could take a JabberJaw approach...
WHo should build your engine? A mechanic. Preferably a good one.
Tires? Round ones. That hold air.

Just having a little fun...

;) ......:cool:

[Matt Fisher]

If you upgrade the size of the motor and the compression, you'd probably be well off to consider a hotter cam than the XR. Remember, it's considered a mild cam for the dirt bike, which is the same motor as the EX (a smidge more compression). Lots of people use the HRC cam in stock XR's, why hold yourself back with a small cam?

GT Thunder, TC, and a host of others all offer drop-in cams that will offer you more performance than the XR, especially given your long-term goals of FCR, porting, etc.

The XR cam's not a bad cam, it's just a bit small, IMO.

I think the cam choice also has to do with the piston compression and size. higher the compression,,then ya need a hotter cam.

Do ya think the GT thunder, TC racing, or HRC cam is gonna give someone $200 more power over a XRcam,,since they cost so much more??? I just couldn't see payin that much more money for .05 HP gain or whatever it might be..

[ChadEXer]

Rico When I talked to Terry about the porting and polishing with a stock carb I told him some people said it wouldnt make much of a difference with a stock carb and his exact words to me was "thats BS" He said he doesnt even recommend an aftermarket carb at all with the 416. He said the best thing to do is just take the choke out of the stock carb and leave it at that!!

[Matt Fisher]

The GT Thunder cam is only $150.
http://www.geocities.com/gtthunder.geo/cat2set.html

[Holty]

quote "Note: Unless you have a both a high flow exhaust and carb. it is useless to due the full race porting on the 400EX due to the large valves and ports."

[Dave400ex]

Rico, a TC Cam is $179 to $209. That`s not bad.

Hey Rico
I was just wondering since u have the 416 kit( iknow they ask u this all day) but i wanted to ask some 1 with the kit.
Can u beat a Raptor(stock) or with basic upgrades?
I wanna get a big boy kit for mine but im not sure if i should get a 440 or a 416 it seems a lot of people ahve both now days.I ride with 2 raptors and im tired of hearing it from them about how much faster they are than the 400's.

[kabd69667]

The only cams i know that are drop in's and over $300 are the hrc cam i think and one of the curtis sparks drop in's. When i called sparks, a guy told me his "speal" on cams. He said that he has a scale from one to ten on cams. The stock being one. Their first drop in is about a 3 or 3 and a half. I'd say that would be like the xr cam. Then they have a more agressive cam for $350. He said it was about a 6 or 6 and a half. Then he said they have their full race cam that requires springs and hard faced rockers. This is about a 9 and a half or ten. If you want to do serious motor work, dont' waste money on an xr when you can just save your money and buy a more agressive cam.

Originally posted by Zoku27
Hey Rico
I was just wondering since u have the 416 kit( iknow they ask u this all day) but i wanted to ask some 1 with the kit.
Can u beat a Raptor(stock) or with basic upgrades?
I wanna get a big boy kit for mine but im not sure if i should get a 440 or a 416 it seems a lot of people ahve both now days.I ride with 2 raptors and im tired of hearing it from them about how much faster they are than the 400's.

I've never raced a raptor with this setup but others with the same piston compression and cam,,have stated they can beat stock raptors and run with piped raptors,,,but I can't say because I've never done it..the 416 kit is a very impressive power boost.

[Dave400ex]

Yeah for $300 the 416 Kit is awesome. You can`t beat it.

[Honda Guy]

Marcums sells it (including boring) for $155 is I missing somthing? or are you just including the price of a cam?

[Ex'rMike]

Does anyone know what the lift and duration of the XR 400 cam is. I would like to compare to someother cams before I buy. I am also curious to see the difference between that and the 400EX. Thanks
EXerMike

[kabd69667]

Originally posted by Honda Guy
Marcums sells it (including boring) for $155 is I missing somthing? or are you just including the price of a cam?
Thats the piston, boring the cylinder, gaskets i think, and cam

[Dave400ex]

Honda Guy, the $300 is with the XR400 Cam.

ExerMike, the XR Cam is not that Wild of a Cam. TC and Sparks make drop-ins that would add more power than the XR Cam. You will also pay more too.

[Tommy 17]

mines a tc cam the guy had to press sumtin off it mayb it was a compression release i have no idea what its called... but the cam was 205$

[MIKE400EX]

EXERMIKE
Lift Duration@.050"Lift
Intake Exhaust Intake Exhaust
stock 400EX cam .316 .302 234 238
XR400 .326 .321 240 244
WB All Around .345 .335 240 248
HRC .350 .339 254 256
WB Track .350 .345 256 256
WEB 450/451 .350 .345 256 256
WEB 479 .378 .378 250 250

These are what I've found by measuring, ads, and talking with cam grinders. Many shops will not give out their specs even if you buy their cam. They are only approximate values>>>but very close. The numbers don't tell the whole story; ramps, centerlines. lobe centers etc. may/will vary too. Hopefully this will help. If anyone has more to add - please do!
Remember - cams are one thing that bigger is not always better!

[JustRace]

Check this site (http://www.motojoe.com/atv/whitebro/engine.htm) it has a lot of info on the big bores, cams, and valve info for all sorts of quads.

[Matt Fisher]

Mike400EX, that is relly helpfull.

Anybody have the specs on TC racing's cams, or GT Thunder?

What's the maximum lift on stock springs and/or valve guides.

[Dave400ex]

I would also like some Info on TC Cams.

[400exBro]

Has any one tried the wb all round cam???
It has more lift and duritation than the xr 400 cam but WB clams it is supposed to be the same as the xr 400 .. It is a little more than the xr, but will it perform better than it too????
thanks
400exBro
Also what is meant by core charge?????
On this site http://www.motojoe.com/atv/whitebro/engine.htm it shows on the all round cam that there is a core charge of $123

[Honda Guy]

Has anyone tryed the all around cam from WEB it like $80 are they good?

[Dave400ex]

All of the Cams are good in their own way. Honda Guy, are you doing Motor Mods? I would get a Cam from a Engine Builder like TC, Sparks, CT, LRD, FST, Powroll, Pro Fab, or Fischer. Those builders have Cams built for their Motor Mods. If you get a TC Piston you should get a TC Cam. I just think a Engine Builder Cam would be better.

[Holty]

when you buy a cam most places require you to send in your stock one(core). when you send in your stock cam the core charge is refunded back to you. if you don't send it in, they keep the core charge money.

it is the same way with alot of auto parts........(ie, alternator, water pump, etc)

[Scott]

I had a bad experience with a Webb cam, actually it was in my younger brothers 300EX. Webb's are regrinds, or at least they were a couple years ago, that's why the price was so low. His webb all-around ate the rockers and wiped a lobe in a very short time (les than 20 hours on the motor). I don't know about all the other cams out there, they may be regrinds as well, but if I were spending my cash for one, I wouldn't get a reground cam.

Ask your performance shops, they'll be able to tell you which ones are reground cams and which ones are new castings.

Ok... so you got your 416 piston and you got your xr cam or whatever and your ready to put it in. Reading the Mickey Dunlap interview at the home page brought somethin to my attention. Now im no expert so i was wondering what hes talkin about when hes saying things like squish cleance and stuff like that. He also mentioned that useing the stock gaskets will not let you take advantage of the true commpression ratio that is advertised. Does anyone have any info on that. Which is the best way to go?????

[400exRacerX]

This is what you get when you order the xr400 cam, 416 piston, and viton valve seals from Marcums.

[Quadfather]

You get K&N filter cleaner and oil with a 416 kit?

[shook]

Just about all cams are regrinds especially all your performance cams sparks TC Gt thunder they all are regrinds WEB makes W/B cams and gt thunders cams Bud fischer recommends all web cams that s what he uses W/B soon will be carring Hot cams made by pivot works they say are just drop ins but they have only been making cams for about a year, and are now getting ready to market there cams but who knows they may not have been out long enough to know if hardening rockers is nescessary but all the companys who used to tell you that you didnt need to now are highly recommending it now that the 400ex has been around a while they are realizing its hard on rockers and bigger cam just shortens there life.An as far as messing up a web cam in 20 minutes you should have still been in the break in stages if you dont break them in correctly they will all wipe lobs or you had to much valve spring pressure one did you run any assembly lube on it when you put it in also its not a good idea to break one in using synthetic oils either.

[Scott]

Thanks for the info on the reground cams Shook. BTW, I said hours, not minutes.

[James70214]

Ok I am going to order the 416 kit and a cam, Probably te xr cam, but what are the best reading on a cam. I race motocross, so I want the best cam for under 200 and do not require any other mods(ex.hard face rockers)

[Dave400ex]

TC makes a Drop-In Cam for MX that Costs $205. You could also check out the GT Thunder.