New 400ex mod? Ported intake

[RNL]

Just curious to see if anyone has ever seen this before. I have not heard of this mod till I came across this video on Youtube. What do you guys think, it worth trying? Got to wonder how much it would add to throttle response. IMO, it can't be any worse than removing the choke for more airflow......right? Need some of the gurus to chime in on this.

http://www.youtube.com/watch?v=I5sxe23D6Q4

[chronicsmoke]

I would be guessing, but I think it can be removed without any ill effects..

I can't see them putting it there to cause turbulance, it looks more like a casting flaw in the rubber. Do it and report back!:muscle:

[ish416]

Occasionally these will come from the factory with a bit of left over rubber from when it was molded. Cleaning that out could help if your's needs it. Otherwise, there will be no gains.

[RNL]

Occasionally these will come from the factory with a bit of left over rubber from when it was molded. Cleaning that out could help if your's needs it. Otherwise, there will be no gains.

For what it's worth the owner of the vid said there are gains in the mid to upper rpm's.

[Longdong]

For what it's worth the owner of the vid said there are gains in the mid to upper rpm's.

I call BS! It may help alittle but you would not be able to tell without a dyno. Even then just doing that i bet it wouldn't show up on a dyno. Another "placebo"mod!

[Baileygunns]

I wouldn't bother unless you are port matching a port job... If you decide to do it, leave the manifold on the head and make sure its a smooth transition from head to manifold. Looks like there's still a lip on the head side in the video.

[ish416]

For what it's worth the owner of the vid said there are gains in the mid to upper rpm's.

For whats it's worth, I installed a graphics kit and a black power band and gained 8 hp in the upper-mid low range.


Seriously, this is old stuff. Pause the video at 1:40, you can clearly see that the intake into the head is much smaller than intake boot. Doing this will not affect anything, unless as I stated, your's has the excess rubber that was never properly trimmed off.

[sickmojave]

I wouldn't bother unless you are port matching a port job... If you decide to do it, leave the manifold on the head and make sure its a smooth transition from head to manifold. Looks like there's still a lip on the head side in the video.

This is what I did and didn't notice any difference.. Just made me feel better knowing it was right...:cool:

[Zakradu398]

Just curious to see if anyone has ever seen this before. I have not heard of this mod till I came across this video on Youtube. What do you guys think, it worth trying? Got to wonder how much it would add to throttle response. IMO, it can't be any worse than removing the choke for more airflow......right? Need some of the gurus to chime in on this.

http://www.youtube.com/watch?v=I5sxe23D6Q4

My intake boot is port matched to my intake ports.

http://i148.photobucket.com/albums/s31/zakrad_u/Mobile%20Uploads/IMG_1043_zpsff16678d.jpg (http://s148.photobucket.com/user/zakrad_u/media/Mobile%20Uploads/IMG_1043_zpsff16678d.jpg.html)

[400exshop]

My intake boot is port matched to my intake ports.

http://i148.photobucket.com/albums/s31/zakrad_u/Mobile%20Uploads/IMG_1043_zpsff16678d.jpg (http://s148.photobucket.com/user/zakrad_u/media/Mobile%20Uploads/IMG_1043_zpsff16678d.jpg.html)

who did that port job? also your boot doesnt mach your port work, the boot need to be open up alot more and when you do a port job you port the head and cut the valve guid bottoms off to make it flow better and it is smooth all the way thro.:D

[Zakradu398]

who did that port job? also your boot doesnt mach your port work, the boot need to be open up alot more and when you do a port job you port the head and cut the valve guid bottoms off to make it flow better and it is smooth all the way thro.:D


It is :p I couldn't get a good pic though..

[wilkin250r]

Port your intake boot, grind the welds out of the header, take off the choke, and add one of them fancy regulator/rectifers that is supposed to shut off electricity when your battery is full, and you've got yourself an extra 1/2 horsepower my friend! Drag race your friend, and you might be a bike length ahead of him after four miles!

[Chukkinsod]

I would agree but still don't think this will improve anything noticeable. As stated above there is still a lip from rubber to metal...best to port match entire setup not just intake but also exhaust ports to match you exhaust setup. IMO

[cheater13]

Any way to make these air cooled engines breathe better is good. Even if it's little, it still helps somewhere IMO.