300ex big bore?

[genoapb]

I am looking to confirm something I read. Im told there are different types of big bore kits some need the bottom cases to be bored out to fit the sleeve and some dont. What is the biggest kit I can get and not have to bore the cases? Who offers these kits, I didnt see it at profab or powroll?

[44oEX]

I think you can go to 330. as long as you don`t go to a big stoker kit ( 395 ) I don`t tink you have to bore the base but I could be wrong. as far as where you can get it I live in canada so sorry but I can hepl cause I would get it up here.

[Aceman]

Out_Sider and I both have the Profab 330 pump gas kits. When I slid my cylinder down onto my cases the 330 sleeve just barely fit in the hole, so I doubt you can go any larger than that. Profab has all the kits listed on their website, just give Scott a call, he's super friendly and willing to help you out anyway he can. By the way, this 330 kit is all I have for an engine mod and this thing rips now.

[Diedrich]

yeah i believe the 330 is as big as u can go..330 is the same size as cylinder as a stock on the outside its just larger on the inside(walls are thinner) the stock cylinder fits perfectly into the cases..its suppose to..go with the 330..you'll be happy

[genoapb]

Does the 350X head flow any better than the 300ex head, stock for stock?

[Out_Sider]

Originally posted by genoapb
Does the 350X head flow any better than the 300ex head, stock for stock?

:huh

[Cody_300ex]

Originally posted by genoapb
Does the 350X head flow any better than the 300ex head, stock for stock?

Yea ive seen people put stock 350x heads on 300s and 250s. But how? Has anybody on this site done it before?

[hondaexryda]

go with 330 big bore or stroker 395

[Ryan300exxx]

What are some websites where I can see who sells the big bore kits? I couldn't find a webite for pro fab. What is involved in the install of one of these kits, reliability, and potential problems. I'm not looking for any great details just some quick info. Thanks.

[xc400ex]

Yeah ive saw the 350x head on a 300ex before. The 300ex, 250x and 350x motors are very near identical.The 350x and 250x will swap clutch and flywheel sidecases..same bolt pattern for cylinder and head..BUT the stroke is different im thinking. I know the bore is. I really dont see it being much of an advantage and the downside is on the 350x head the cam doesnt ride on bearings...so if theres any wear the head will have to be replaced whereas the 250 and 300ex heads have bearings. The other problem is a custom header will have to be made since the 350x is dualled..and a stock 350x headpipe wont work because the frame rail gets in the way been there done that.

[xc400ex]

www.powroll.com
or contact mickey dunlap of fourstroke tech thats the kit i would recommend..he use to have a website but its down..www.fourstroketech.com

[Aceman]

Here you go www.profabatv.com (http://www.profabatv.com) Four Stroke Tech (FST) doesn't have a website anymore. You can try pm'ing Mickey Dunlap or maybe someone can get you his phone number.

[dirtmomma]

Can you guys tell me what all came w/ your 330 kits?? What size piston,what brand of piston, did it come w/ new valve springs ect ect
Thanks, ;)

[44oEX]

You can get anything you want but it only comes standard with the piston ( I don't know what size ) and rings and gaskets.

[Aceman]

My Profab 330 pump gas kit was around $445, with the sleeving. I had Profab do the resleeving and boring/honing also. The kit includes a 80mm JE 11:1 piston and rings, sleeve, top end gaskets, and Scott will throw in a couple of oil filters. I would like to get a hotcam eventually to unlock some more power. But as is, this thing flat out pulls so much harder than stock and all I have is a pipe and filter.

[dirtmomma]

Originally posted by Aceman
My Profab 330 pump gas kit was around $445, with the sleeving. I had Profab do the resleeving and boring/honing also. The kit includes a 80mm JE 11:1 piston and rings, sleeve, top end gaskets, and Scott will throw in a couple of oil filters. I would like to get a hotcam eventually to unlock some more power. But as is, this thing flat out pulls so much harder than stock and all I have is a pipe and filter.

So you paid that price for resleeving,piston rings ext & boring?? Hummm well hell I'm almost there if thats the case, I just did a 75.5mm High dome Wiseco piston, rings,ect. & bored it!! Sounds like I could just get a bigger piston, have it resleeved, & I would be to a 330?? I'm curious if anyone knows what my compression would be?? I still have the stock cam,& valves too. I'm tryin to figure out if I wanna go to 330 or a stroker, it almost seems like I'm close to the 330 & if thats the case then I need to go bigger I NEED MORE POWER:D :devil: :macho

[Aceman]

Dirtmomma

Just call Scott up at Profab and ask about the 330 pump gas kit. It is a true 11:1 piston. The wiseco you have now is stated as an 11:1 piston also, but I believe it was Mickey Dunlap that said it really wasn't accurate, that the compression was less than that. Boring produces more hp than torque and stroking produces more torque than hp, I believe. You can rev a bored motor faster than a stroked motor. Since you race, I think you would benefit more from a 330 kit. You can always stroke it later:D