would this be a good increase in power

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tjrap350

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I have been trying to figure out what cam I want and I want a lot more mid to top in power so i thought about going with the web .430 cam. my question is I have a hmf,k&n,re-jetted, stock gearing, so if i went with this cam and a valve spring kit would it be a good increase in power with the stock piston or would i need to get a higher compression piston to go along with this?

also what all is involved in doing all of this? cost?
 
what brand and compression did you go with? also you have to get it bored for that new piston right? if so what did it bring your cc up to? or can you go with a stock bore, what do you recommend?
 
ok thanks so go with a 10:5:1 piston a .430 cam and a hd valve spring kit? how much labor would be involved as far as getting it put in?
 
Well i wouldnt do stock bore depending on what condition you cylinder is in and how old the bike is and how hard its been ridden. If you go stock bore you have to get cylinder honed still to make sure its smooth.

I went with a wiseco 10:5.1 compression piston thats bored .020 over for $76 on ebay. The webcam .430 lift with kibblewhite race springs i got those to things for like $180 on ebay.

As for labor costs i now it was like $50 to get my cylinder bored .02 over and honed. Then like $30 to get the springs put in. The rest of it i did myself with a little help from my friend. Its not that hard to put it all back together and time it. Its tuff your first time but if you have some help and fallow the manuel you will be fine.
 
You might want a new timing chain too, i got one just because i was going to be rebuilding it and i didnt want to break back into the engine later on just to put a new chain in it.

Hope i helped.
 
its a 2007 with about 40 hrs on it do i still need a new chain? was the setup you went with worth it and did you notice a lot of low-end power loss? so did the bore you did bring it up to a 366?
Thanks for all your help
 
You need more compression for that cam, or step down to the .390 cam. You'll be surprized how good the .390 cam will work.
 
ok so that .390 cam with all the other stuff i mentioned would be a good setup with a little power increase? i see that wiseco has a .20 and a .40 over bore, what would be the difference in this as far as power goes? also if i was to go more compression and get the .430 cam how much can i go with pump gas and how would i get more compression? shave the head? and how much would it need to be shaved
 
I went with the mods i listed earlyer and it saw a huge power increase....not huge but a lot better. But i also added an edlebrock carb, uni clamp on filter, and hmf slip on. I think the compression and the pipe made up for the lost bottem end. I also geared the from sproket up to a 14 tooth running 20" tires. And with the compression i have i run pump gas and it runs perfectly fine.
 
compairing the power increase to my bros stock warrior engine....when i go from mine to his you can tell a huge difference in power expecialy in top end power. Also when i noticed his would bog out some what in 6th in like snow and stuff and i just punch it and it just gets to high rpms fast. I love the set up im running now.
 
When I had my warrior I had a hmf exhaust/k&n filter, 430. web cam and 10.25-1 wiseco piston. Didnt notice any loss in low end power with the 430. cam. I did regret getting the 430. cam though, I would have rather bought the 390. instead because I ride mostly tight woods.
 
Guys between cams and higher compression your talking like a difference of 3 or 4 HP.

this may sound stupid but what exactly do you mean?
are you saying that a cam and high compression gives you 3-4 hp?
 
3-4 hp is a good amount to me so with my hmf,k&n kit, re-jetted,10:5:1 piston,.430 cam and hd valve springs im looking at about 24-26hp maybe? and around $500 in all parts and labor? does all that sound about right?
 
man thanks for all your help? i have learned a lot but still have a few questions. what bore should i go a .020 over or .040. and should i get the je 10:5:1 or wiseco 10:25:1? when i go to get it bored i'm sure i have to take the motor out right? do you have to advance the timing any?
also is there anything that i could do to save some money on labor? how hard is it to install a cam and springs?
 
you can do all of it inside the frame, I took my head out and it was simple, if you have a little mechanical knowledge, it is simple to do on your own, guys like jason P and Dave help out a lot on choosing the correct setup, I ride woods a lot and open spaces, I think I am going with the .430 and advance my timing a tad bit to try and pick up some lower end
 
you can do all of it inside the frame, I took my head out and it was simple, if you have a little mechanical knowledge, it is simple to do on your own, guys like jason P and Dave help out a lot on choosing the correct setup, I ride woods a lot and open spaces, I think I am going with the .430 and advance my timing a tad bit to try and pick up some lower end
ok thanks. what brand of piston you going with and what bore size?
 

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