426ex Build

[thebig450es]

Im thinking im going to make my 400ex a 426 finally
Im thinking of going with the 88mm 13:1 JE, Im still inbetween hot cam stage 1 and 2, CRF450 cam chain, GT thunder head studs and have them install the head studs and do the bore, xr400 gaskets, spal fan, and do a 450r carb an zrpilot adapter. I already have the big gun FULL exhaust / K%N and air scoops. I'll be running E85 for the 105 octane. I ride alot of woods and hill climbs but drag also.

[PaRedneckRiders]

Sounds like you have thing pretty much planned out. If your going 13:1 on a 426 i wouldnt run a stage one cam. I go either stage 2 or 3 but probably stage 2.

[sneaky11]

You will have a motor builted for at least a stage 3 cam IMO, with that kind of c/r you definitely gonna kill your motor with a stage 1.

look at webcam and megacyle cam... i'll probably go with the webcam 479 with this setup. big lift with short duration, you'll have crazy torq all the powerband, alot of air/fuel mix to cool the chamber, cuz you gonna build alot of btus. you'll need hardfaced rockers with that cam. If you want a drop-in, got HC stg 3.

You'll probably have to look for an HD rod too!! I think your OEM one gonna have real hard time with a 426 13:1!!

you'll have to pull out your sparks key with that.

Hope you will do a thread for this nice rebuilt with some pics!!

:D

[trailrider894]

Originally posted by sneaky11
You will have a motor builted for at least a stage 3 cam IMO, with that kind of c/r you definitely gonna kill your motor with a stage 1.

look at webcam and megacyle cam... i'll probably go with the webcam 479 with this setup. big lift with short duration, you'll have crazy torq all the powerband, alot of air/fuel mix to cool the chamber, cuz you gonna build alot of btus. you'll need hardfaced rockers with that cam. If you want a drop-in, got HC stg 3.

You'll probably have to look for an HD rod too!! I think your OEM one gonna have real hard time with a 426 13:1!!

you'll have to pull out your sparks key with that.

Hope you will do a thread for this nice rebuilt with some pics!!

:D

The stock rod will work just fine. I've never seen anyone break one because of having to much power and some of these guys are pulling some massive HP!

[sneaky11]

Originally posted by trailrider894
The stock rod will work just fine. I've never seen anyone break one because of having to much power and some of these guys are pulling some massive HP!

Good to know!! I was planning on swappin mine for a carrilo.. probably spends that money on turbocharger!! kiddin':blah:

[thebig450es]

Im planning on a detailed build, with pics. Yes im planning on taking my sparks key out. I am looking for alot of torque for a cam

[CJM]

I hope you are investing in heavy duty head studs, a larger oil cooler, and larger oil tank. Otherwise its gonna blow up due to the heat.

[thebig450es]

The Gt thunder head studs are a must in the list, whats a good aftermarket oil cooler and larger oil tank

[thebig450es]

I should have enough in the budget for a port and polish, also can i use +1 vavles with the set up im thinking of

[sneaky11]

Depends on the cam you choose, on the p&p you do, etc... +1 intake, +1 exhaust, or both +1... if you want low to mid end, go exhaust .. if you want mid to top end, go intake!! race-cut your valve and do a 5 angles valves seat ...

For the cooler, I suggest you to look for FST oil cooler... that will be very helpfull to reroute some oil to the top of the head for your setup!!

or you can just buy a tranny oil cooler, and put it in-line with the first one, or put a bigger one to replace the oem, and grab a SPal fan to match with!! Both are good, but FST style is the best IMO.

[thebig450es]

With the 13:1 and a stage 2 hot cam i should still have enough low end. Dose the JE kit come with a new sleeve? or will i be fine borign out the stock one

[CJM]

Word of warning:
Your getting into territory where your gonna make to much heat, the most I would run is a 12:1 piston. Anything more and oyu run the risk its gonna heat and blow up head gaskets with ease-even with all the cooling mods.

[thebig450es]

http://cgi.ebay.com/ebaymotors/HONDA-TRX400EX-TRX-400EX-JE-PISTON-3MM-OVER-13-1-_W0QQcmdZViewItemQQhashZitem43a3974186QQitemZ29050 7407750QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

http://cgi.ebay.com/ebaymotors/NEW-HOTCAMS-HOT-CAMS-HONDA-TRX400EX-400EX-STAGE-2-CAM-_W0QQcmdZViewItemQQhashZitem35b03b3a68QQitemZ23058 9938280QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

How do these look for the piston and cam?

[honda400ex2003]

es you have a pm on the t-4. was looking to get some info from you one it.


marc you also have a pm regarding the topic of the day haha
steve

[CJM]

Originally posted by thebig450es
http://cgi.ebay.com/ebaymotors/HONDA-TRX400EX-TRX-400EX-JE-PISTON-3MM-OVER-13-1-_W0QQcmdZViewItemQQhashZitem43a3974186QQitemZ29050 7407750QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

http://cgi.ebay.com/ebaymotors/NEW-HOTCAMS-HOT-CAMS-HONDA-TRX400EX-400EX-STAGE-2-CAM-_W0QQcmdZViewItemQQhashZitem35b03b3a68QQitemZ23058 9938280QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

How do these look for the piston and cam?

Same stores I got my stuff from, they sell quality parts.

@Steve: Replied to PM.

[thebig450es]

Thanks for all the help, so many options, i got the tax refund today , better than i thought, so i may be doing more on the head work

[82toyota]

are u going to get it dyno and see how much power it make just asking

[82toyota]

are u going to get it dyno so it tune right and see how much it make.......just asking

[thebig450es]

Yes im planning on dyno tuning it, im also thinking i may mix vp-110 or vp-113 with the e85 to help cooling and det.

[thebig450es]

I just had sugury so the project is going slower than i thought, im starting the tear down. I found Lukes racing with is about an hour from my house, but they dont deal with gt thunder to do the studs. I really what the head studs with the 13:1 compression. I got the fan ordered. Im still in the air which cam. The hotcam stage 2 or go gt thunder or sparks.

[sneaky11]

I'm building a 416 12.5:1 Cp piston with the stage 3 Hotcam. I think with a 426 13:1 you could go a little bit more agressive if you want to!! That can help letting go the heat.