Which one first (cam or piston)

[MorganAllen]

Right now I'm looking for the best benefit for performance. Should I either go with a wiseco 11:1 piston bored .080 over or go with a stage 2 webcam with the necessary components. I'm not agianst going with a bigger cam, but I don't want to have low cylinder presseure because of low compression and a big cam. Also the piston is advertised as being 11:1 but is this the true compression just installed in their or will the cylinder have to be decked? Out of the things I have chosen which will make the biggest difference, I'm wanting a strong midrange and better topend. The mods I have so far are: K and N filter, 400ex carb, cobra exhaust (no I'm not changing it), and a unlimited rev box, 14 tooth sprocket. Thanks for the help.

[Sjorge450R]

Originally posted by MorganAllen
Right now I'm looking for the best benefit for performance. Should I either go with a wiseco 11:1 piston bored .080 over or go with a stage 2 webcam with the necessary components. I'm not agianst going with a bigger cam, but I don't want to have low cylinder presseure because of low compression and a big cam. Also the piston is advertised as being 11:1 but is this the true compression just installed in their or will the cylinder have to be decked? Out of the things I have chosen which will make the biggest difference, I'm wanting a strong midrange and better topend. The mods I have so far are: K and N filter, 400ex carb, cobra exhaust (no I'm not changing it), and a unlimited rev box, 14 tooth sprocket. Thanks for the help.

okay well right now the 400ex carb is prob holding you back. You have a stock engine with a big carb....so its pointless. Go for the piston first. You will notice a nice gain there but only go to a .020. You wont notice a difference between .020-.080. Just if you go to .080 and suck something in, you need to resleve to stay under 300cc. While its open I would jsut get a cam even tho a cam can be installed in under an hour. And if i were you even tho you are extreamly against it, i would get some sort of builders pipe (Sparks,TC) i recommend the Supertrapp IDS-2, but hey, if you dont wanna change the pipe you may suffer later down the road, when that pipe is robbing your power.

[honda250xrider]

why wont you change the exhaust do you like sound and no power that it produces? more than likely will make more power with the stock exhaust than that racket maker just take that for what its worth. its up for grabs on what you are going to do you can still get a cam and just deck the head a little to bump up compression. I would recommend both. I've used web cam .320 grind and it has worked great on a several engines that i have used them on.

[MorganAllen]

If i find a sparks or a wb head pipe/ hmf i might change it. I just put the 400ex carb on, yes its jeted correctly. To me it ran a lot better with more bottom and mid range. I'm saying your wrong, but it worked great for me. One of you talked about milling the head how much did you mill it? Do you know the the cc of the combustion chamber before and after? Do you know the compression it raised it to, stock is 8:9:1? Thanks agian

[250X_project]

Yeah the 400EX carb (when properly jetted!) will give even a slightly modded engine better throttle response. Great mod.

If you have the money I would strongly advise you to do both a high lift cam and a .020 high compression piston. Also a good port job would do you some good. All of this after a better pipe though.

Yes, stock compression is 8.9:1. I have figured the combustion chamber, configuring the piston crown, to be around 35.56cc's.

[250X_project]

Also, if you had to pick just one I'd go with the piston, just because a rebuild is always good for performance anyway, especially a lighter, higher compression piston.