looking for some opinions on my mild engine build

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96yamahawarrior

96yamahawarrior

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its been a long time since ive posted here.. my warrior has been on the backburner this last year while i was building my 1980 k5...
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but over this winter its my quads turn.. im going to be doing a overall rebuild, but i need some advice on the engine.

i want to do just a simple top end job, and add a little power. im going to do a 10.25:1 standard bore piston, timing chain, vitos +4 key and a cam.

my questions are;
what cam would you recomend for a basic build?
and does this sound like a decent plan?
 
Go .20 over wiseco piston, timing chain, hot cam stage 1 and an upgrade carburetor. skip the Vito's key and get an oil cooler setup.
 
I'm not sure "basic" build includes upgraded valve springs and you need a port and polish to use that cam to its full potential the stage one and two hot cams push the stock ports to their limit.
 
i dont want to get into a port and polish. for the head i just want to throw a set of valve seals and cam in, if i got with a stage one would i have to do anything?
 
Trust me if you want this rebuild to last do it right and get it bored. Every tolerance will be correct and it will last much longer than if you just honed it.
The key isn't very strong and likes to sheer while introducing more unneeded heat into the engine for a trade off of a very small power gain. Not worth it.
You don't have to do anything for the hotcam at all just drop it in and go.
 
alex456123 said:
Trust me if you want this rebuild to last do it right and get it bored. Every tolerance will be correct and it will last much longer than if you just honed it.
The key isn't very strong and likes to sheer while introducing more unneeded heat into the engine for a trade off of a very small power gain. Not worth it.
You don't have to do anything for the hotcam at all just drop it in and go.
Click to expand...
about how much would it cost me to get the cylinder bored? and i never heard of that key sheering like that! thanks for the heads up
 
Apparently Alex thinks I've never built an engine before.... Truthfully if you want full potential with any Cam you should have the head ported but in your case you already have the head off so I say put good springs in it and use the Web .390. It's just simply a better cam than the HOTCAMS and needs no more porting than either of the HOTCAMS. The ramp rates on the lobes are faster and more aggressive, they're trying to get you more a/f in the engine under the area of the lobe itself. Ported or unported the engine will still take advantage of the area the more aggressive cam gives it. Were not talking about peak flow numbers here, were talking about a cam that will help deliver power BETTER in the area that the valve is in most which is low lift. I hate misconception. It leads to a theory becoming a general rule and then ends up as a fact after a while.Misconception here being that the .390 cam needs port work but the HOTCAMS do not. That's false. What the Web cam does need that the HOTCAM doesn't is more spring pressure to control the valve.
 
alex456123 said:
I'm not sure "basic" build includes upgraded valve springs and you need a port and polish to use that cam to its full potential the stage one and two hot cams push the stock ports to their limit.
Click to expand...

The head just doesn't flow past .400" of lift. Thing is, is the web .390 or .413 worth the added $100 cost of springs. For my second build I decided no and just used the hc1

Skip the key and use this piston
http://www.wiseco.com/PDFs/YamahaWarrior350.pdf
 
'00 WO-YA! said:
Apparently Alex thinks I've never built an engine before.... Truthfully if you want full potential with any Cam you should have the head ported but in your case you already have the head off so I say put good springs in it and use the Web .390. It's just simply a better cam than the HOTCAMS and needs no more porting than either of the HOTCAMS. The ramp rates on the lobes are faster and more aggressive, they're trying to get you more a/f in the engine under the area of the lobe itself. Ported or unported the engine will still take advantage of the area the more aggressive cam gives it. Were not talking about peak flow numbers here, were talking about a cam that will help deliver power BETTER in the area that the valve is in most which is low lift. I hate misconception. It leads to a theory becoming a general rule and then ends up as a fact after a while.Misconception here being that the .390 cam needs port work but the HOTCAMS do not. That's false. What the Web cam does need that the HOTCAM doesn't is more spring pressure to control the valve.
Click to expand...

I'm just going off of what I remember Mickey Dunlap saying lol
 
its not that i dont want to go all out, but i have a ton of other **** planned for this build, rebuilding my works shocks, a arms, header pipe, led light bar...... the list goes on! i just want to freshen this old engine up, while adding a bit more power.
 
The .390 cam and a JE 10.5 with the 2mm over bore would work good for you man. It's far from an all out combo really. Yeah going that big on the bore makes the cylinder useless in terms of another overbore but if you treat the engine right it will still serve you for a long time. Also the .390 does need springs but that's not a bad idea anyway. Up to you bro, it's also going to set you up for future growth if you want it.
 
Put the springs in it. Engine will be quieter, and, like James said, you will be able to make improvements in the future without taring the head down again.
 
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