DRW: Building a 4Valve 374cc Warrior Motor

[88WarriorBoy]

I don't see why they wouldn't with how inovative this is to the warrior and raptor 350 world

 

[Gen1Pat]

What weston has failed to say is that it was MY idea! Lol. Seriously, it was.

 

[88WarriorBoy]

DANG lol not given CREDIT where credit is do. Great Idea Pat

 

[duneracerweston]

Ill admit its your idea when i see the sub name "the King" in blue and black under my name like a admin! Lol

 

[rappy'97]

This is good to see. People like this are what keeps this sport interesting.

 

[duneracerweston]

Your welcome :tup:

 

[bones]

I will run duels if I can get a second gytr cheaply, otherwise its gonna be a single, it would be cool to have both set ups to compare the two.

found one for a yfz, you could mod to mach yours

http://www.ebay.ca/itm/Yamaha-2006-...Parts_Accessories&hash=item20c8911244&vxp=mtr

 

[duneracerweston]

Thats still more then I want to spend on it, I really like the look of a single

 

[DeadLastRacing]

How tight did you pack it? The tighter, the better.

with the ladies.......:iagree::iagree::evilface::tup:

 

[duneracerweston]

thought this might interest you guys.

valve sizes

YFM
intake
+1 intake 40mm
std exhaust 34mm

XT
intake 28mm ea.
exhaust 25mm ea.


port sizes.

YFM
intake 37.5mm
exhaust 37.8mm

XT
intake 24.9mm ea.
exhaust 25.0mm ea.

so it looks like the key to break 45+ with this head is gonna be in the port work. a factory XT is 27HP with a catalytic converter, a stuffed up exhaust, and 2 tiny butterfly carbs.

so i dont see any problem betting to 45-50 hp, thats what im shooting for anyways :tup:

 

[88WarriorBoy]

wow lol the exhaust port is bigger than the intake port lol thats wierd

 

[beastlywarrior228]

Id give ya 40 max

 

[duneracerweston]

Beast, the xt hits 37 with 10.5:1, cams and a pipe. Stock the xt uses 22mm twin carbs, and a tiny filter and crapy headpipe. 40+ is no issue on a p&p 374 camed oversized valves, custom exhaust, and a 39mm fcr. 40 would be on the low side.

 

[jasonp]

Id give ya 40 max

I agree.

 

[buzzy613]

wait im a little lost it the carb is on the fornt are the intake ports also facing that way? or is the head almost the same?, ive seen this setup almost exact on a yz450f dirtbike i belive but any way im here to see how it turn out!

 

[Gen1Pat]

The timing chain is on the right side of the engine on the XT dirtbike. So, you have to turn it around to work on the warrior. When you do that, the intake valve face forward, and the exhaust backward. So, you have to make it a front mount carb.

 

[buzzy613]

thats what i thought but wouldnt the motor have to spin backwards to have the motor to hae it run right or no?

 

[Mathius]

thats what i thought but wouldnt the motor have to spin backwards to have the motor to hae it run right or no?

That's an interesting question..
Cause wouldn't the timing be backwards?

 

[YAMAHAULER]

Good point!!:iagree::iagree::iagree::iagree:

 

[beastlywarrior228]

Shouldnt make a difference, just the cams will spin the opposite way