airmancams 78mph 350X

[MR ATC]

This is where the lighter piston, rod, and crank come in at. Again, I said there wouldn't be a substantial upgrade in RPM's, but there would one, however it will be minute and very slight.

Billy it's been tried all it does is rev quicker but not higher.

no 350X motor as a 350 will go over the stock rpm's

i use the 10,500 as a guide only because thats were my tach topped out at and i know how some people can be, they need to see it to belive, so i use that as a referance most of the time. but in reality it will rev to almost 11,500 and this is why i say over 11,000. no matter what you do to a 350X motor and keep it a 350 it will not go over that limit.
you can go bigger but you'll lose RPM's you can go smaller to gain RPM's but its not a 350. making a smaller motor rev higher is no problem.

[smokinwrench]

Well, than lets decrease the stroke and increase the bore and make it a 350 that way.

Then you could have the best of both worlds tighter rapping(12,000 plus from the shorter stroke) and then you could still have the size that will give it the hp.

Josh

[MR ATC]

Billy already mentiond that. but now you will have a smaller rod moving a bigger piston. not gonna rev higher

[Billy Golightly]

I concede Bill. I can't prove I can make a same as stock displacement 350X motor turn faster then 11.5k. BUT, "In Theory" I do believe its possible, hehe.

[MR ATC]

"in theroy" quads are better then trikes

[MR ATC]

ok guys in chat tonight Kilborg finally came up with the answer...TURBO...that is the only way you will get a 350X to rev over 11,000+ rpms. i was waiting to see if anyone would come up with it. some good theroy's though.

[NOS_350X]

hahaahah, sorry to cut in guys.....but damn..we got some determined guys on the board.....im jsut wondering how many more pages this is gonna go on for.....haha, i dont mind, i read it every day and lmao, .

........some ppl just gotta admit it when there wrong......
*cough*mratc*cough*

i think this argument is probably the best one ive seen on here. they stayed on topic completly (not the amc's 350 but the rpm's) and its completly clean. and both sides have solid points backing there theorys

[MR ATC]

except one thing mines not theroy but actuall experiance, test, and results.

[NOS_350X]

except one thing mines not theroy but actuall experiance, test, and results.

i knew i should have kept quiet. this is going to start it up again

[KASEY]

Billy already mentiond that. but now you will have a smaller rod moving a bigger piston. not gonna rev higher

this is not true,,,,, you will have a SHORTER rod ,,,, not a smaller rod and there is no reason that it won't be as strong or stronger,,,,,, the 350 engine is a trailprotrailprotrailprotrailprotrailprotrailprotrailpro anyway,,, there are no classes for it to race in,, thats why not very hop up parts,,, or much intrest in building them,,,,, you can believe there will be plenty new yammy and honda 450 quads that will breach the 12,000 rpm barrier without any problems,,,,, and if you don't believe that wake up its 2003!!!!!

[SpeedBump]

Can't you just get some RPMs outta simple "breathing" mods? Last time I checked it worked well poppin on a free flowing air fliter, losing the airbox lid and larger headpipe with a less restrictive silencer. Get small amount of rpms and isn;t that what he is after? Seems in all the dyno tests I have seen, the simple mods I have described gives an engine a small increase in MAXIMUM HP, but a much broader powerband with a higher maximum RPM. OKAY, now Bill can tell me why I am wrong....he will....trust me.

[TimSr]

At the risk of appearing to live in the real world on planet earth, lets see if if Ive got this right. A guy runs his 350X all the way wound out, and screaming down a stretch of highway in high gear, and wishes to raise his top speed, and some of you guys think engine modifications to turn more RPMs is a practical way to do that?

Most stock motors of any type (without rev limiter) are perfectly capable of turning enough RPMs to quickly turn a motor into shrapnel if you try to maintain high RPMs. It doenst matter what mods you do. If you raise the RPMs of a motor in order to achieve a higher cruising speed, yes, in theory it will achieve a higher speed for a few seconds, but all you will really accomplish is reduce the number of seconds it takes for the screaming motor to grenade. Since you cant maintain extremely high RPMs for more than a couple seconds, engine modifications to increase RPMs are totally irrelevant in any discussion of raising top speed other than how long it takes you to reach it. If I understand the gist of this post, and MrATCs answer to my "why would you want to" question, guys are trying to figure out what top speed to gear for, so they can road cruise at a lower speed in midrange high gear specifically so they dont launch it.

As much is it pains to to publically agree with MrATC, Ive really gotten tired of seeing the extent of silliness this post has reached! Please let it die!!!!!!

[MR ATC]

Kasey, your correct i misspoke i should have said "shorter" however on a 350X motor that will not effectivly increase rpm's. the 450 comparison is irelevent becuase we are not talking about them. i admit other motors can increase there rpm's. aditionally you are misinformed about the amount of hop ups avalible for the 350X motor. it is one of the most versital motors in an ATV and countless combinations are avalible to modify them. the aftermarket is still to this day heavilly involved in them as there are more parts avalible then any other 3wheeler except the 250R.

speed if i answer will you promise not to "punch" me out the breathing mods will increase H.P. but not revs. they will let you rev quicker but not higher.

Tim Sr. unlike you, i have no problem agreeing (sp) with you. and this is the point i've been trying to make. a 350X already revs to high stock, and will grenade itself (i have the broken rods, cases, pistons, cylinders, to prove it.) if the 11,000+ rpm's are maintaned.

[AirManCam]

Mr.ATC what do you mean no one in here has ever built a custom 350x motor. I have! I had built it then it wasnt fast enough. So I took a Xr 500 motor and put it in the 350x chassis. And let me tell you what that would fly!
But I am going to have to agree with TimSr. I think this post is getting a little long and stupid dont you guys think?

[MR ATC]

sorry airman i was not refuring to you just the "350Xperts" arguing with me about RPM's.

for the record what mods did you do? did it increase your RPM's