460 big bore kit

[northern]

I was thinking about putting a big bore kit in my 2002 400ex. Does anybody know what the horse power gain would be? I believe it has 26 horses stock. I already have a big gun race series exhaust, after market airbox lid, no choke, and a k&n air filter.

[BadA$$440]

going u to a 460 involvles taking it apart, down to the crank, buy a stroket crank, bore the cylinder, etc, etc, etc. If all done right and u get a good piston, cam, carb, etc. You should end up with 40 +/- HP.

[oynot400]

I did a For Dirt Only 463 stroker kit. According to Mike, with the mods I have, head work, ect. I should be right at 50 hp. I will get it on the dyno some time this winter to verify that.

[BadA$$440]

ooops, guess i was wrong.

[oynot400]

You were close. It is a BIG IMPROVEMENT over stock. :devil

I have a For Dirt Only 463 on the way! If you want some big powr I would suggest calling Mike at FDO ph# 740-967-1078

[BadA$$440]

how much is the FDO 463 and what is all included in the price?

[oynot400]

Mike is willing to work with you to build what ever you want. Since I already had some head work done and a cam all I needed was the crank, piston, and clutch work. I think I have a little over $800 in mine. I also got a deal on a crank, which helped out alot.
If you had to get your own crank sent out to get stroked and have all the head work done. I would guess in the $1500 to $2000 range, depending on what you wanted. The best thing to do is to call Mike, he will be more than willing to answer you questions. :)

[ChadEXer]

oynot, I would really like to see what your bike will do on the dyno. If FDO can get your bike to 50 HP then I will be willing to give him all my respect! I know a guy that has a Trinity 465 stroker that pushes around 48 HP and Harry at Trinity builds one he!! of a motor!! With your mods, I would guess probably around 42-45 HP, but Im willing to be proven wrong!!!

[oynot400]

I am going to put it on the dyno this winter. One of the machine shops in town is building a wheel dyno and he is going to use my quad to get things set up. Then when he is done I will go in and will do some dyno runs. He is hoping that it will be up and running in Feburary.
As far as the 50 hp, that is what Mike told me. He said depending on the head work and cam I already have in may vary some. I would like to know for sure myself. Don't worry when I do get it on the dyno I will be posting the results. ;)

[ChadEXer]

I should have mine back together next weekend and Ill be off to HighLifter to see what their dyno says!!! Tom told me he built my motor mainly for torque(Good for drag racing) so the torque will be the unbelievable number but he said he guarantees at least 55HP but he told me dont be surprised if it runs a tad over 60! I am shooting for around 65-68 with the Methanol on it!! but you never know!!

[shaneb]

the trinity 465 uses a short rod FDO does not ....

The trinity 465 may not run any better than a well setup 440 becuase of the short rod .....

Shane

[shaneb]

here is a 473 by FDO making over 50 ...

FDO 473 (http://www.geocities.com/gtthunder.geo/news_set.html)

I guess this is 88.5mm piston 7mm stroke

[oynot400]

I was talking to one of the guys that I ride with. Anyway he melted his 400 down last weekend. He claims the piston looked like a softball. :huh This is why you rejet after installing a pipe and filter.
So he is taking it to a local engine builder. Leney Mumm, of Mumm's the word racing. He does build some kick ***** motors and he has one or two of the fastest guys in Iowa riding his quads. Brad Phillips being one of them. He is building him a 440 that is suppose to be in the 50 hp range. I don't understand how he can do it without stroking it. He claims it is a straight bore job, high compression piston, cam, and head work.
I tried to talk him into a FDO kit. But he wanted to work with a local builder. To each their own.
I talked with Mike about rod lenght. I don't know if anyone uses a long rod stroker. FDO uses a stock lenght rod and a 6 mm stroke in both his 463 and 493 kits.

[shaneb]

what piston size in the 463. Is it 88mm ??

[oynot400]

I think so, it is the same for a 426.

[shaneb]

so you must have a custom piston with a pin height 3mm higher than stock ???

How hard is it to get these pistons ??

[Sick0]

Wouldn't that send the piston throungh the head.

I have a dyno report on one of FDO's 440's in front of me right now that reads 46hp 47hp 47hp and 47.5hp with different CDI boxes. the 47.5 was with a new air intake they are testing and the 46 was with the stock cdi. This motor was done a year ago and has a full season of racing on it. It is also the motor that put out the most power on the dyno at the LL national out of all 4strokes that were on the dyno.

Now to the 463
Heavy duty rod
Stoke and Balance Crank
Piston
Cam
new valvue seals
trail port
Gaskets
and labor

This motor should put out about 48hp as is. tax and all total is 1496.45

nathan

[shaneb]

when you stroke the top of the rod will be 3mm higher than stock when you raise the pin height it will lower the top of the piston ....

Shane

[oynot400]

Originally posted by Sick0
Wouldn't that send the piston throungh the head.
No, because the wrist pin height in the piston is moved up 3 mm also, to lower the piston.
As far as shaneb question. Yes it is a custom piston. JE makes the pistons for Mike. You can either get the piston from Mike or the engine builder you went with. I am sure if you called JE or another piston builder and tell them what you have they will send it to you. But I would go through the engine builder, so you make sure that you get the right piston. :D
And yes, a 6mm stroke will move the top of the rod 3mm higher on TDC and 3mm farther down on BDC. ;)

[Chef]

Wow, your gettin 50 for under $1000? Geeez....If my 480 was over 65 on methanol, I wonder what it would have pulled as a 505?:eek:

[ChadEXer]

Originally posted by CHEF440EX
Wow, your gettin 50 for under $1000? Geeez....If my 480 was over 65 on methanol, I wonder what it would have pulled as a 505?:eek:
Probably not much more if any at all!!! Tom said that going from like a 490 to a 505 wont really add hardly any horsepower, but it does add a bit of torque!!!

[shaneb]

ChadExer how is your 505 doing ??

I am going to get a 493 from fdo ....

Any over heating problems ???

Shane

[Chef]

Originally posted by ChadEXer

Probably not much more if any at all!!! Tom said that going from like a 490 to a 505 wont really add hardly any horsepower, but it does add a bit of torque!!!

But that little bit of torque would help in a drag race, for getting out of the hole.

[ChadEXer]

Originally posted by CHEF440EX


But that little bit of torque would help in a drag race, for getting out of the hole.
Thats exactly why I done it!!
Tom said my bike wont have an encredible amount of horsepower, only about 55-60 on gas, but the torque will be incredible! And I know he is right because at Little Sahara I pulled a 3rd gear start(on accident, thought I was in 2nd) and it pulled it in the sand with haulers as good as a stock 400EX will pull on dirt!!!! I hope to have it together pretty soon, Tom has been saying for the past 2 weeks, "ill get it right out",,,,one thing I have to say, he doesnt get in a hurry!! Kind of pisses me off,,,I couldnt be more happier with the way Tom built my monster, and I can understand he is very busy but he should say that and not Ill have it right to you!! thats by far the only complaint I have, but I dont mind waiting!!