Port ad Polish Exspence

[HondaRacing23]

I already have a hot cam stage 2 and a je piston 12:1 I think and a full HMF system. I just bought a doug eicher 440EX carb kit and im thiking about getting porting and polish done. WHo can do it and what am i going to exspect to pay getting it all done. I think im going to get some hardend rockers too. Who could I get to do it a nd how much am i looking at Thansk...

[hawiianpwr]

I had Colby port and polish with the 3 angle valve job and it made a nice difference. The throttle response is better and it just seemed to complement the other mods real well.
Do it its worth it:)

[terko440]

Dont forget that you dont want to harden your rockers with that cam or you will wear it out prematurely

[HondaRacing23]

The guys at work told me that my loud ticking was from my rockers not being hardend. are my stock rockers good then? I didnt know that but ill take your word for it. HOw much is porting and polishing? can i only get it ported and polished and thats it? or is there more to it. do i have to get a new piston and rings and what not? thansk

[MarkyNark]

There are couple kinds of headwork that can be done. First of all, porting is an art. Find someone has very good experience with it or knows someone that has very good experience with it. By the way, in the 4-stroke world, its referred as porting - not porting and polishing. With 4 strokes, you dont want the intake of your head "polished". You need an air buffer between the flow of the air/fuel mixture and the aluminum wall. If that surface is polished smooth, the atomized air/fuel mix will hit the smooth polished wall and basically run on the walls - this robs power. Secondly, you can also increase the valve size. By porting and increasing the valve size at the same time you now have a race head. There are a couple of ways to do this. The stock valve pockets can be machined out by 1mm larger. This is the least expensive way to do it. The other way is to remove the valve pockets and have 2mm oversize installed (this is very expensive). If the right port work, a 1mm oversize valve combination can give just as much horsepower as a 2mm oversize combination at about half the price.

Hope that helps...

[HondaRacing23]

So just get the head ported and get bigger valves? Thats all will need to do? Wont have to replace my piston or anything else. Im gonna call around tomorrow and see if i cant find someone to do it for me reasonable. I got the Doug Eichner carb ordered lastnight so im hopeing that it will do something for me better then my old junk carb. i have had nothing but problems with it. thanks man

[MarkyNark]

Originally posted by HondaRacing23
So just get the head ported and get bigger valves? Thats all will need to do? Wont have to replace my piston or anything else. Im gonna call around tomorrow and see if i cant find someone to do it for me reasonable. I got the Doug Eichner carb ordered lastnight so im hopeing that it will do something for me better then my old junk carb. i have had nothing but problems with it. thanks man

As already mentioned, you will need the hardened rocker arms. Who the heck knows why some cam manufacturers dont require that - its totally stupid - You need them! What valve springs are you running?

Glad you hear you got the Doug Eichner carb - I love mine, and you'll really enjoy the power it produces, not to mention the ease of tuning it. The FCR produces a little more on the top end, but the low end and mid range is owned by the Edelbrock.

By the way, I've learned the hard way that the Edelbrock carb does not like VP U4. I just had some crutial components replaced due to corrosion from the U4. I switched to VP C12 - the same fuel that Ducan racing uses.

If you going to get a race head, get at least a 12:1 piston. JE makes a fine superlight piston. Duncan carries several of them as well. I liked my 13:1 a ton. But, it was bit to dangerous with the nitrous combination.

I also had my flywheel lightened. The only disadvantage is that you have to work your throttle more at very low RPMs. But you'll gain tons by being quick revving. By the way, the 13:1 hinders this. The superlight JE 12:1 enhances this. Please run at least 110 octane with either one of these pistons. If you run pump gas your engine will be toast.

You might consider heavy stay bolts - Personally I didnt run them for years and never had a problem. I did add heavy stay bolts after adding Nitrous.

[HondaRacing23]

So i do need to get hardend rockers with a hot cam st age 2. i was told that yu didnt need them. I have a 12:1 JE piston now with a hot cam stage 2 i still have the stock valve springs in my bike should i change them too. i only have a little over $300 to spare maybe 500.oo is that going to be enough to get this all down? thanks

[400exrider707]

The hotcams are a drop in cam, if you harden your rockers you will prematurely wear out the cam!!!. Leave the rockers unless they are worn, then just replace with new ones.

[MarkyNark]

Hot Cam Specs for Stage II

Intake:

Lift: .354
Duration: 254 Degrees

Exhaust:

Lift: .350
Duration: 248 Degrees


Thats a pretty mild cam. Hot cam does not recommend hardweld rockers. But I've never heard of a cam that is so soft that the rockers will tear into the cam. Just for comparison check out the specs for the Web Cam:

Intake:

Lift: .350
Duration: 256 Degrees

Exhaust:

Lift: .345
Duration: 256 Degrees

Web does recomend hard weld rockers with thiers. There's not a lot of difference in the lift between the two. In fact, the Hot Cam has more lift in the intake than the Web. It's lift that kills rockers.

If I were you, I would put Hot Cam on the phone and ask them if indeed the stage II cam will be ruined by running hardweld rockers. If they say yes, then I wouldn't get them - because they are too soft. In my opinion, you want everything to work - long term. Why keep replacing components?

JMHO

[400exrider707]

Originally posted by MarkyNark
Hot Cam Specs for Stage II

Intake:

Lift: .354
Duration: 254 Degrees

Exhaust:

Lift: .350
Duration: 248 Degrees


Thats a pretty mild cam. Hot cam does not recommend hardweld rockers. But I've never heard of a cam that is so soft that the rockers will tear into the cam. Just for comparison check out the specs for the Web Cam:

Intake:

Lift: .350
Duration: 256 Degrees

Exhaust:

Lift: .345
Duration: 256 Degrees

Web does recomend hard weld rockers with thiers. There's not a lot of difference in the lift between the two. In fact, the Hot Cam has more lift in the intake than the Web. It's lift that kills rockers.

If I were you, I would put Hot Cam on the phone and ask them if indeed the stage II cam will be ruined by running hardweld rockers. If they say yes, then I wouldn't get them - because they are too soft. In my opinion, you want everything to work - long term. Why keep replacing components?

JMHO


the lift itself isn't as important as the material used to make the cams. Web hardwelds them and then grinds them to their specs therefore hardweld rockers are a must. Im not saying the rockers are going to literally chew your cam apart, but it will cause insignificant wear.

[cals400ex]

hardwelded cams may ruin stock rockers. the stock cam, TC cam, hotcams, etc are not hardwelded and thus you will use stock rockers.


a lightened flywheel actually made my bike a little slower for dragging. i did try it, even though a few of the larger engine builders didn't recommend it, and it turns out i should have listened to them. oh well, i kept my stock flywheel and that went back into the bike.


many of times larger valves can actually hurt performance if you don't need them. they can actually hurt air flow due to them being larger. i am not saying it will help or hurt on your setup but most of the engine builders i talked too said there isn't much to be gained, even from a port job. there were talking about my engine (TC cam,11:1 426, thin head gasket, no base gasket, thermal coated x-6 exhuast, piston head, and piston skirt, etc).

you will need to check with the piston manufacturer about the +1 valves. the valve reliefs may not be cut to accomodate larger valves. this means you have a good chance of a valve hitting the piston.

[MarkyNark]

Well I've learned something today thats for sure. Hot Cams are not re-welded cams. Therefore, they do not need the hardweld rockers. I've always run web cams for the EX which are hardweld. There are several other cam manufacturers that do both re-weld and billet steel. The re-welds from them also require hard weld rockers, but most of the billet cams do not. So, it is best to follow what the manufacturers recommend for rockers.

As far as the head work, it is an artform. There are good porters and bad porters. Mine works really well with the 1mm oversize valves and I did notice very good HP increases. You dont have to carve the heck out of the EX to improve velocity and flow. But also keep in mind, larger carb, bigger cams, exhaust all increase flow. The idea here is to keep the head from being the choke point.

Most aftermarket pistons give enough room for 1mm over. The JE 12:1 superlight does and several of the Duncan pistons do to. But you'll want to verify that with the manufacturer to make sure they match.

As far as the lightened flywheel, I'm gonna maintain my ground on that. I know of no lightened flywheel that would hinder a drag. All you are doing is lightening the rotating mass. The larger stock flywheel helps maintain idle and low RPM performance. To overcome the later, all you have to do is work the throttle a bit more. A heavier fly wheel will never work to an advantage in a drag race. The best engine builders I know also agree with me on that.

Maybe you are thinking about a lightened crank. I've tried a lightened crank and didnt have good results. I suppose there are lightened crank kits that would work better. To me, my lightened crank didnt match the counter balance and I felt the whatever gains came from the lightened crank were nixed by the vibration. The manufacturer of lightened cranks says thats not a problem - all I know is that I didnt get any noticible gains. So, Im still pretty neutral on that.

[gojk]

Originally posted by MarkyNark
There are couple kinds of headwork that can be done. First of all, porting is an art. Find someone has very good experience with it or knows someone that has very good experience with it. By the way, in the 4-stroke world, its referred as porting - not porting and polishing. With 4 strokes, you dont want the intake of your head "polished". You need an air buffer between the flow of the air/fuel mixture and the aluminum wall. If that surface is polished smooth, the atomized air/fuel mix will hit the smooth polished wall and basically run on the walls - this robs power. Secondly, you can also increase the valve size. By porting and increasing the valve size at the same time you now have a race head. There are a couple of ways to do this. The stock valve pockets can be machined out by 1mm larger. This is the least expensive way to do it. The other way is to remove the valve pockets and have 2mm oversize installed (this is very expensive). If the right port work, a 1mm oversize valve combination can give just as much horsepower as a 2mm oversize combination at about half the price.

Hope that helps...

This is not completely correct. They DO polish the exhaust ports, which helps the gases escape quicker, and also takes away the oppertunity for carbon to build up in the ports. On the intake side they will leave them a little rough so that fuel does not collect on the ports and also leaving them a little rough increases turbulance which causes the fuel to atomize better, giving you a better burn.

Also remember, while porting bigger is not always better. You want the best velocity while still having greatest amount of flow. I would call one of the engine builders close to you area and asking these questions. I am sure they will answer better than most of DIYers on this site.

[HondaRacing23]

WIll I be fine with what i have. Je piston 12:1 and hot cam stage 2 and a doug eichner carb? Will i ruin my motor if I dont do the others? I know i may not get the most out of my motor not doing it but wil it harm my motor? I dont race yet and im looking to get into here soon. but even then i may not do much more to the bike other then changing a couple simple things. if it isnt going to hurt my motor then i wont do anything. Also has anyone ever changed there starter gears? is it very hard to do it. My makes a hard clunking noise when trying to start could that be the starter gears thats what i was told. thanks for all your help i have learned tons

[MarkyNark]

HondaRacing23

You should be fine with those cams. Sorry the thread got a bit muddled. I think we can all agree that if you want to build further, find someone local to you that has a good reputation when it comes to porting.

I'm an advocate of porting - especially with your carb and cam. But removing too much material will hinder your performance. Like I said before, porting is an art.

On the subject of your carb; One thing to think about that wouldn't cost a lot is to consider a different throttle control. The stock thumb throttle does not provide enough cable pull to fully utilize the Edelbrock 38. I went with the twist throttle which really helped alot. Duncan has a twist kit kit specifically made for that carb. If you dont like twist throttles, you may do a little research into the Moose billet thumb throttle. I know a lot of folks use that one for other carbs that helps with the same problem.

[HondaRacing23]

i actually just bought a motion pro twist throttle the other day and love it much better then the thumb. will that work with that carb or will i have to get s different one? Its cool that u kinda swamp the thread but thats what there here for for Q&A and all of you have help me out a lot. THanks again

[MarkyNark]

As far as the throttle goes, Motion Pro has different models with different pull capabilities. The Motion Pro I have is 1/4 turn to full with the Duncan cable. So, your's will probably work, you'll just need a different cable to work with your new carb.

[HondaRacing23]

i have the motion pro turbo twist throttle it came with a brand new cable will that cable work or what one will i need. thanks

[MarkyNark]

If the cable is specifically for the Motion Pro AND the Edlebrock, you'll be fine. If you got the twist for the stock carb, it wont work with the cable you got. All you have to do is ask for a replacement cable that works with the Edlebrock carb as well as the motion pro twist.

[cals400ex]

Originally posted by HondaRacing23
i have the motion pro turbo twist throttle it came with a brand new cable will that cable work or what one will i need. thanks


where did you get your piston from?



gt thunder told me the lightened flywheels will not help in a drag race on the 400ex. mine wouldn't pull high rpms as well as the stock one. it was to the point that i would lose around 3-4 bike lengths in a drag to the middle of 5th gear or so. it is nice that i have a buddy with a bike that is very similar in speed as mine so we can modify and then compare. the stock flywheel went back on and i gained the ground that i previously lost. the way i see this is that the lightened flywheel does not have as much stored energy, thus will not pull higher rpms as well. there is probably a perfect midpoint between too light and too heavy. i don't know where that is at but my lightened flywheel wasn't lightened as much as some of the builders too. it was still enough to noticable slow me down though. another problem with lightening is getting them balanced. i would send any flywheel off to trailtech to have them balance it. an improperly balanced flywheel could very well slow you down significantly too.

[MarkyNark]

Originally posted by cals400ex
where did you get your piston from?



gt thunder told me the lightened flywheels will not help in a drag race on the 400ex. mine wouldn't pull high rpms as well as the stock one. it was to the point that i would lose around 3-4 bike lengths in a drag to the middle of 5th gear or so. it is nice that i have a buddy with a bike that is very similar in speed as mine so we can modify and then compare. the stock flywheel went back on and i gained the ground that i previously lost. the way i see this is that the lightened flywheel does not have as much stored energy, thus will not pull higher rpms as well. there is probably a perfect midpoint between too light and too heavy. i don't know where that is at but my lightened flywheel wasn't lightened as much as some of the builders too. it was still enough to noticable slow me down though. another problem with lightening is getting them balanced. i would send any flywheel off to trailtech to have them balance it. an improperly balanced flywheel could very well slow you down significantly too.


In my opinion, stored energy will only help your motor idle smoothly and/or take less effort to maintain a constant speed. Think about it, you put big huge tires and wheels on a truck and it takes more effort to spin them up. Likewise, you have a steel sprocket, and heavy chain, you'll do better to make them lighter because it will rev quicker.

I've had my lightened flywheel in there and it does help. I hit the throttle and it revs quick. The affect is not as great as cams. So, if something else changed, you can get rid of the benefit pretty easily.

[prepracing]

well why you guy's are on the subject of horsepower ...what about this latest craze where people are actually de-porting their heads (making the ports smaller) and claiming more horsepower. I've seen dyno's on streetbikes that did gain HP's with this done, but they run twice the rpm's quads run. Just not sure if I would trust it in my quad or not, might be ok if your wide open all the time, but what about when you have to lug it around how would it run. I ride with a couple people that have this done and have talked to several people at GNCC's that have it done also and they seem to be plesed with it. Any body have any opinions on it ???

[HondaRacing23]

I got my pistons and cams from C&D racing and had my work install them for me. They gave me a pretty good price on them.

[cals400ex]

a lot of people do try smaller ports. this is called high velocity porting. most of the time this kind of porting will move the power lower in the rpm range. every bike and every head is different though. some will respond better, some will respond worse.



mark, i am not saying the lightened flywheel didn't help in your situation. i had my lightened by laz and i was clearly slower when dragging. instant throttle response was good but the bike was simply slower when dragging. laz did back up my results too.

[MarkyNark]

Originally posted by cals400ex
a lot of people do try smaller ports. this is called high velocity porting. most of the time this kind of porting will move the power lower in the rpm range. every bike and every head is different though. some will respond better, some will respond worse.



mark, i am not saying the lightened flywheel didn't help in your situation. i had my lightened by laz and i was clearly slower when dragging. instant throttle response was good but the bike was simply slower when dragging. laz did back up my results too.

cals400ex

Oh I understand what you are saying - and I've been in a similar situation with the stroker. All I am saying is that the lightened flywheel alone will not do that. Its simply not scientifically correct. Rotating mass reduction alone simply will not hinder speed. Im not calling you a liar, at all. There are some other possibilities with your motor and your situation. Perhaps something else changed at the same time you did the flywheel?

[cals400ex]

this is what i did:

i dragged my buddy on a road so traction wasn't an issue. i would quickly pull in 2nd and 3rd gear. by the time we hit the middle of 5th gear, i was around 3 bike lengths ahead of him.

i then took out the stock flywheel and put in the lightened one. i also drilled a 2 inch hole in my air box lid and put in one of gt thunders velocity stacks. i raised my mainjet 1 size too. i put the same oil (but new of course) back into the bike. i raced my buddy and by the time we were in the middle of 5th gear, i was 1 bike length behind him. i left the flywheel in my bike for a few weeks thinking it may need to "get used to" the bike. i was consistently behind my buddy when dragging. i never once beat him in a drag with that lightened flywheel on. the higher gear we would get into the more of an advantage he seemed to have. we were a somewhat even race until 3rd gear or so. which that sucks because with the stock flywheel in i would have been a few bike lengths in front at this point in time.

enough with that so i put the stock flywheel back in. i figured maybe that velocity stack screwed things up or possibly something else. i got everything back together and i left my same jetting and velocity stack in. i was once again around 3 bike lengths in front. so i came to the conclusion the velocity stack really didn't do much for me when dragging and also the lightened flywheel slowed me down. the same oil went back into the bike and everything once again. there were no other changes made to the bike. i could simply feel that it didn't want to pull high rpms very good. the lightened flywheel ran great when messing around and when you needed quick throttle response. you just had to shift sooner, which isn't what my bike wanted i guess. i tried to shift sooner with no luck. i tried to let it pull as high as the stock flywheel and it just wouldn't do it.