header welds

[russellsroost31]

hey guys ive been hearing of this old trick of grinding the header welds on a 400ex for more proformance and i just wanted to know that if anyone on the fourm has ever done this and if it works well or is it just a waste of time

[D3structive]

I believe a bunch of guys have done it, they said it only gives about a 1/2 hp gain but some is better than none. I don't think it matters if your running stock box and pipe though.

[russellsroost31]

ehh if i only get tht much then its not worth my time

[chronicsmoke]

Originally posted by russellsroost31
ehh if i only get tht much then its not worth my time

I'd still do it.. If you're running an 80 dollar air filter, and justify the cost by saying it adds an extra .3hp, why not do a free mod that makes another .5 on top.

I'm not a super believer in the grinded welds, yes I agree it will increase performance.. but an after market header isn't 'pointless' as some members have stated. it would still add a couple points more hp.. The diameter of the aftermarket header on my 426 is def. larger than a stock one..

[quadmanw]

If you have a filter and aftermarket pipe then go for it. It's not a hard task and any flow helps!

[Mr-Sleeper-34]

http://i50.photobucket.com/albums/f339/MR-4DOOR-SR20DE/2004%20Honda%20Sportrax%20400ex/2011-10-04194449.jpg

^I had it done along with having my header ceramic coated to reduce heat. I haven't had a chance to install it yet. It's been in bubble wrap since last year.

[400exjoker]

i did my stock header welds but i also added a hmf slip on and i got a big difference in throttle response and some low to mid power but i cannot tell u if doing the welds after you already have an aftermarket slipon will do anything... what i can tell u is the stock welds are sloppy as all hell and for me it was worth it to clean them up there was slag down in the pipe and the welds were blocking a good amount of airflow, i would get some new gaskets if you do decide to take and grind the welds, because when i took mine off the gaskets were shot and i wouldnt suggest reusing them

[05DodgeDakota]

It's worth it if you already have the pipe off or if you have an afternoon with nothing better to do

[dxcody]

Might as well...

You looking at around $5 to do a mod. (gaskets)

You improved the way the air goes in, Now just do a little something to help it flow out.

[quadracer556]

although i havent done it (running a full sparks x6) the hp isnt as big as the throttle response gain but for the cost/time i'd say y not.

[Drfat400ex]

I did it, got some more throttle response, a tad more power, and I think it's a bit louder too, my buddy didn't do it on his and we have the same pipe and it seems quieter.

[russellsroost31]

well if you guys say to go for i then i will

[Drfat400ex]

Yeah and while you've got the header off clean it up good with some steel wool and then it doesn't look all crappy.

[TheAwesomehonda]

Originally posted by Drfat400ex
Yeah and while you've got the header off clean it up good with some steel wool and then it doesn't look all crappy. Yeah that or a wire wheel on a power drill.

[russellsroost31]

well i did it and i noticed a lil more bottom end but not to much
it also has a little different sound and whe i first start it up it tends to bog if i hit the throttle but when it warms up its fine

[400exwhipper]

What's the best tool to do this with and will it leak if I dont replace the gasket?

[Drfat400ex]

Originally posted by 400exwhipper
What's the best tool to do this with and will it leak if I dont replace the gasket? Either a die grinder or a dremel, whichever you have, and I didn't replace myn and it's still fine so probably not.

[dxcody]

Replace those 2 little crush gaskets.

I think they are a whoping $3 on ebay and if you dont your header will leak, which is probably the sound difference he heard because it doesnt sound like he changed his.

Also you have to be sure to get the old crush gaskets OUT of the head. They tend to get stuck in there.

Why wouldnt you replace them and make sure its done right, esp when its so cheap to do it the right way?

I swear some of you take info in one ear and it passes right through and out the other.

[russellsroost31]

i didnt replace mine and it doesnt seem to be leaking
now do u think i should rejet again

[dxcody]

Originally posted by russellsroost31
i didnt replace mine and it doesnt seem to be leaking
now do u think i should rejet again

Well just because you dont "think" its leaking doesnt mean its not.

There is no reason to re-jet if your not going to replace the gaskets because if it is leaking, you will never get your jetting correct anyways.

EDIT: I dont mean this to sound like im being a d*ck, im just saying i have been there. I know how it goes with air leaks.

Airleaks are bad news bears, and jetting gets all f*cked up over them.

[russellsroost31]

the gaskets were still pretty good so thats y i didnt replace them

[dxcody]

Originally posted by russellsroost31
the gaskets were still pretty good so thats y i didnt replace them


Those are crush gaskets though, that is what i am trying to tell you. Once they are crushed they cannot be reused.

[russellsroost31]

ok

[Mr-Sleeper-34]

Originally posted by dxcody
Those are crush gaskets though, that is what i am trying to tell you. Once they are crushed they cannot be reused.

^Thanks for the heads up.


Originally posted by russellsroost31
ok

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=160507451712

^Here is a link bro.

[TheAwesomehonda]

Yes they should be replaced but no they will not nessesarily leak if you don't replace them. They will be crushed on the head and be somewhat hard to get off sometimes. dxcody is right they should be replaced.

[hocman123]

Originally posted by dxcody
Those are crush gaskets though, that is what i am trying to tell you. Once they are crushed they cannot be reused.

i have had my header on and off maybe 10 times on the same gaskets bc i had a lot of engine problems. and i know they are still good b/c i check for leaks after i put it back on for the last time. now i am not saying replaceing them isn't a good idea i was going to but after i checked and didn't find leaks i didn't replace them.

[300exBorg]

makes absolutely zero sense to not replace them. i personally could not ride it knowing there's a possibility of an exhaust leak. like previously said that's bad news bears lol

[Mr-Sleeper-34]

- Exactly, considering the gaskets go for $2.50 a pop.

[russellsroost31]

ima rebuild the exhaust so ill buy them