12.5:1 vs 11:1 Compression on 440EX

[BurnMX]

I'm doing research on installing a 440 kit and I was wondering what differences compression would make? More power vs. reliability?

Also, any input on the subject is welcome..

I'm planning on going with:
Edelbrock 440 Carb
Wiseco big bore kit (done by my local shop)
hotcams stage 2 cam

Is there anything else I would need to complete the engine over-haul to a 440cc monster?

[shamisc]

A properly ported head will make it reap all the 440 has to offer.;) I wouldn't go over 11:1 unless you plan on installing a Carrillo HD rod.

[R3Concepts]

I would not build a 440. A 416 or 426 will pull a 440 all day long. "Local Machine shop" if not done right, it will blow head gaskets all day long... too many things to screw up in boring and sleeving a 440. Do not go with 12.5:1, thats too much compression, unless its done by a top builder, aka Sparks. I run a 11:1 426, hotcam stage 2, edlebrock carb, valve work, hardened rockers, head ported and polished, springs, retainers, and so on.. and I holeshot my freinds 440(same items in motor as mine) by 10 bike lenghts every race. 426 you dont re-sleeve and its super reliable.

[kj400]

Not the 440 vs 4?6 again. but like shamisc said PROPER porting makes the biggest difference on a 440.

R3 just curious why you are running hardened rockers with a hotcam?

[R3Concepts]

A Hotcam stage 2 is still a big lift cam, didnt want to have any problems with the rockers, did everything right the first time. You should still do rockers with a cam, but it they say you can run stock springs and reatainers with a stage 1, but why have problems.

[pnut420]

Originally posted by R3Concepts426ex
I would not build a 440. A 416 or 426 will pull a 440 all day long. "Local Machine shop" if not done right, it will blow head gaskets all day long... too many things to screw up in boring and sleeving a 440. Do not go with 12.5:1, thats too much compression, unless its done by a top builder, aka Sparks. I run a 11:1 426, hotcam stage 2, edlebrock carb, valve work, hardened rockers, head ported and polished, springs, retainers, and so on.. and I holeshot my freinds 440(same items in motor as mine) by 10 bike lenghts every race. 426 you dont re-sleeve and its super reliable.

I had a 426, great motor but your friend really must have a problem with his 440, I mean Ive seen enough to know a 426 is not going to holeshot like that.

I hope you had a custom hotcam made or had your hotcam hardened :huh . The hardened are meant to be used with webcams and other types that call for a hardened rocker. Also if it is not done right a 416 will blow head gaskets all day. All engine builders will say they dont have problems with head gaskes blowing, but it seems like most of them do, they have to convince you why they are a better builder.

[woprs50]

i wouldnt go 12 to 1 or higher without an aftermarket rod thats why i went with 11.2 compression i didnt feel like splitting the cases to install a rod right now i probably should have though with all time ive been waiting on all my other stuff



and R3 concepts or whatever your name is the hotcams are supposed to be a drop in cam that means with your hardened rockers your rockers are harder than your cam which means your rockers are gonna eat away at your cam evenutally

this is alil besides the question but whats the largest compression for a 416 je piston that will run on pump gas???
10.8:1 ??? to weak or little?? just right??
ill be runing hotcam stage 2 cam k&n filterand 416 je kit

[pnut420]

Originally posted by woprs50
i wouldnt go 12 to 1 or higher without an aftermarket rod thats why i went with 11.2 compression i didnt feel like splitting the cases to install a rod right now i probably should have though with all time ive been waiting on all my other stuff



and R3 concepts or whatever your name is the hotcams are supposed to be a drop in cam that means with your hardened rockers your rockers are harder than your cam which means your rockers are gonna eat away at your cam evenutally

yeah that combo is no good. I would not go over 11:1, I had 11:1 and missed 1 shift and boom the rod went, sure the rod might hold 12:1 until it gets loaded up a little to much.

I think if I was running stock piston and missed that shift the rod would have held. Oh well time for the YZ426 conversion

[BurnMX]

Thanks for the feedback guys..

I was told also that I would need to replace my clutch with a race clutch if I was dropping in a 440 otherwise I would blow the stock setup.

The time is approaching.. can't wait.

Is the HotCams Stage 2 the way to go, or are there better options available? I plan to start desert racing once all the mods are done.

Thanks again!

[K_Fulk]

Your clutch should hold up for a while. my original motor was a 440 for over 2 y years and the clutch was still good when i sold it. You may want to throw in some stiffer clutch springs though.

[jasoncarr25]

a stock honda clutch is stronger than any aftermarket. save your money.