I want to make a fire breathing 426.

[yellow400ex05]

Ok I"m going to start saving money up as soon as i start working on wednesday. I want to build a nasty 426ex. So far my plans are a high comp JE 11:1 piston so i can still run on pump gas. I am also thinking about a port and polish, but will it kill the reliabilty? with the port and polish. I am also gong to re-gear it to a 13 tooth up front and 40 tooth rear I want it to have crazy acceleration and low and mid end. What Are some other things to get a little more power out of it besides a FCR carb? This is going to be a mid summer project, so i have time to think about this.

[zrpilot]

Port and polish will not affect reliability.

Here is what I'd do if you are concerned about reliability:
1) HD head studs
2) CRF cam timing chain
3) 8 plate clutch kit
4) HD rod


I'd also do the following (if you have not already done these)
1) Open up the Air box
2) Port and Polish (make sure the port match the intake boot)
3) new valve seals
4) 11:1 JE piston kit
5) 450R carb (lower cost option then the 39MM FCR)

If done right a 426 should make high 30s HP! More if you swap your stage 1 cam for a more agressive cam.

[yellow400ex05]

Originally posted by zrpilot
Port and polish will not affect reliability.

Here is what I'd do if you are concerned about reliability:
1) HD head studs
2) CRF cam timing chain
3) 8 plate clutch kit
4) HD rod


I'd also do the following (if you have not already done these)
1) Open up the Air box
2) Port and Polish (make sure the port match the intake boot)
3) new valve seals
4) 11:1 JE piston kit
5) 450R carb (lower cost option then the 39MM FCR)

If done right a 426 should make high 30s HP! More if you swap your stage 1 cam for a more agressive cam.


how much would all of this cost in the first list along with what i added to it.

1) HD head studs
2) CRF cam timing chain
3) 8 plate clutch kit
4) HD rod
5) JE high comp piston 11:1
6)Port and polish

[underpowered]

Originally posted by yellow400ex05
how much would all of this cost in the first list along with what i added to it.

1) HD head studs
2) CRF cam timing chain
3) 8 plate clutch kit
4) HD rod
5) JE high comp piston 11:1
6)Port and polish

HD studs=$50 instal =$50
CRF chain=$35
8 plate clutch= IMO not needed. i run a barnett in my 426 with no problems
HD rod=$100 for rod install=$75( if you take crank out, if shop takes crank out $150 min to take out crank, plus $75 for rod install) or New crank = $300-400
JE piston= $150 bore=$50-75
P&P=$150-300 mine cost $250
grand total of anywhere from

$650 on the low side with you doin all the work, to about $1500 or so, maybe more if teh shop does all teh work.

what cam do you have? a good cam is definitely high on the priority list if you are gonna do all that work. exhuast?? a full system would be good to.

[yellow400ex05]

Thats alot of $$, but I'm sure i could do it.

How does the 13tooth front and 40 tooth rear gearing sound?

[yellow400ex05]

I have a hotcam stage 1 and HMF slip-on And i have 6 holes in the lid with a twin air airfilter. I should order a header before the build. then I should order the parts.

[ZSK]

Why only a 426?

[yellow400ex05]

I would do a 440 but i would just be too nervous about blowing like 100's of headgaskets.

[underpowered]

Originally posted by yellow400ex05
I have a hotcam stage 1 and HMF slip-on And i have 6 holes in the lid with a twin air airfilter. I should order a header before the build. then I should order the parts.

well if i were you, i would get a larger cam. atleast a stage 2, i run a stage 3 in my 426.

as for the gearing, that is crazy low. i run stock gearin on mine and love it, never did understand the whole 1 tooth down on the 400ex, i tried it and hated it. but whatever you want for gearing. it is cheap and easy to mess with.

[REDRIDDER]

Originally posted by underpowered
well if i were you, i would get a larger cam. atleast a stage 2, i run a stage 3 in my 426.

as for the gearing, that is crazy low. i run stock gearin on mine and love it, never did understand the whole 1 tooth down on the 400ex, i tried it and hated it. but whatever you want for gearing. it is cheap and easy to mess with. 1999-(2007 Honda TRX 400EX
1996-2004 Honda XR 400

Description:
TRX 400EX Stage 3: single-cam motor. More top-end power. Designed specifically for Hot Rods big bore stroker kit. Uses stock valve springs and rockers. *Does not use auto-decompression mechanism. Stock starter sufficient.)


do you have a stroker kit? how well does that work in your motor.what were your gains like its saying that its designed specificcally for a stroker.im just curious about that.this is directly from hot cams web site. For Model(s):
1999-2007 Honda TRX 400EX
1996-2004 Honda XR 400

Description:
TRX 400EX Stage 1: single-cam motor. Excellent midrange and top-end power increase. Not recommended for big bore applications over 426cc. Uses stock valve springs and rockers. *Does not use auto-decompression mechanism. Stock starter sufficient


For Model(s):
1999-2007 Honda TRX 400EX
1996-2004 Honda XR 400

Description:
TRX 400EX Stage 2: single-cam motor. More top-end power than Stage 1 with midrange gain. Uses stock valve springs and rockers. *Does not use auto-decompression mechanism. Stock starter sufficient.


correction i just found this on their site.....Will the 1051-3 Hot Cam work in anything but the Hot Rods big bore stroker kit for my TRX400EX?
All other applications will require the piston to valve clearance to be inspected. so underpowerd keep that in mind.

[red200040ex]

The Hotcams stage 3 cam will work in a stock displacement 400, I have one in mine it's just not really designed for smaller displacements.

[underpowered]

notice is says Big bore-stroker. my ex is a big bore, even though not a stroker. it works great. lots of top end, pulls hard all teh way to the rev limiter. used to have the old stage 2, and i lost a bit of low end but gained some on top with the new stage 3. i don;t have many hours on it, as i installed it just before the sparta race 2 weeks ago and only rode it about and hour before the race and during the race. but from what little i did ride on it, it pulls very hard and has great top end. i love it, but you gotta keep it revved. it was origionally called the stroker cam, but that name was dropped for teh stage 3 name, since it can be used for big bore's to, not just stroker motors