DRW: Building a 4Valve 374cc Warrior Motor

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duneracerweston

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Ok well here it is, what you all have wanted to try but couldn't afford or were to scared to attempt. So here goes im gonna try it with a spare bottom end I got in the shop using a XT350 head and piston, we will see how it goes!

First major issue is the slight issue with the intake being in the front with the XT head, so in the process of waiting on my xt parts to show, thought I would share what im gonna do.

The carb im gonna run is a modified39mm FCR, in its original size it won't fit in the frame, so I deleted the TPS sensor and cup it sets it, also had to cut the drain spout off, fits now :tup:

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Goal of the build is 10.25:1 (so I can tune it without destroying it the first time) a possible, p&p, cam, oversized valves. But I wont know still I find out how expensive the resleeve will cost.
 
HUMMMMM......VERY interesting. Custom header? You are going to have and enclose that filter for the hatfeild trip man, your gunna be sucking up so much chit. But on a side note, I really dig the semi forced intake setup thou.
 
i dont know what ill do air box wise, but the exhaust being in the tail should make it more rev happy have at most a 45 degree bend in it.

My xt head and jug came in today, its donna be a PITA off the bat the head bolt holes are gonna need to modified, they are 6.7mm to far apart if you measure it in a X pattern, gonna need custom cam gears and a good bit of machine work the get the timing chain to work.

on the up side, the timing chain gally is perfecty the right size for the DOHC to run the chain down, and IT FITS IN THE FRAME!! put the empty cases and covers on it and set it in, it fits!

the intake valves are bent up in this head, but ill convert it to +1 valves no problem.

head cc's at 32cc (used greese to seal the valves so its probably a little more then that.)

It even comes with a de-comp lever for you pull start guys!

pics

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That's going to be sweet man I have thought about doing this for along time just never had the funds to try ... Glad some one is giving it a shot

Ps Im hoping for duals on this
 
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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.
 
F yeah, duels would take this build to the next level! There is SO much room on the back sode of the engine now. Hahah. Hummmm, what to put there? An oven box? You can heat up your morning eggs off the exhaust heat!

Is that an empty case?
 
seems like it is going to be pretty nice.Are you using a twist throttle with that carb?
 
seems like it is going to be pretty nice.Are you using a twist throttle with that carb?

It's a fcr off a yfz, so its a thumb.

The motor is empty except bearings.

If yall can help fine a cheap gytr pipe ill do duels. Im hoping to have it at Hatfield to show it off, but we will haveto see what happens with it, gotta get custom timing chain sprockets made so so we shall see
 
i dont see how, the cam gear on the warrior is huge compared to the xt gear, and the crank gear on the warrior cant be any smaller i dont think, ill ask vince when i call him, ive got a list of questions to ask him lol.

and the timing chain gally is off by 7mm so some grinding will be required to make it fit.

we will see, im not spending anymore cash on it till i finish the 2v motor that goes in walle.
 
Yep I packed it with some heavy duty Packing didn't think of steel wool.
Word sure get around quick. The stock Raptor 350 setup I sent Levi sounded better to me.
 
Well, looks like custom cam gears, crank gear and timing chain guides will be needed. This is gonna be a bit more time and custom parts then originally thought. But if it all works out I am gonna see if dirt wheels will wheel it and write a article on it!
 
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