well first off this head was junk to start with so if its still junk no big loss I guess. anyways my head dropped 2 valves and buggered it up pretty good. I had a local performance shop guy do the welding, he's a great welder he's fixed many busted pro stock aluminum blocks so he's no stranger to aluminum, just imports and dohc. he pretty much put a layer of weld over the entire combustion chamber and then I had him weld up the quench pads as well. so I throw it in the cnc upside down today to remachine the chambers and to no surprise its warped all to hell.

so for those of you who have welded heads like this before any tips? i'm guessing you'd want to weld it little by little and keep the heat out of it correct? when I went to pick it up there wasn't nearly enough weld on it to clean it up so I think he hurried it a little and thats what caused it to warp.

probably not worth doing anything with but I'd just like to hear from some expierinced people what to do to prevent such a thing and is there a way to straighten it?

thanks guys, -Shawn

 

Have the head surfaced after its welded.

 

ditto

 

well surfacing the deck is easy, but the cam side is what i'm worried about. the high spot is in the center of the head over the #2 cylinder that has been welded (camshaft side). if you put a straight edge on it you can see that it drops off about .01" from there to the outer edges. decking this side of the head would screw up all sorts of things, even if the cam lobes were to be line bored and honed the physical location of them would be lower in the head causing problems with valve lash when vtec is engaged. valve lash can be adjusted for the primary and secondary cam lobes, but not the vtec lobe, that relies on the cam grind and the pin locations in the rocker arms correct? if the cam was lower in the head, then that "built in" valve lash goes away.

 

Theres a certain amount of warp thats acceptable, but if it goes excessive, camshafts can snap etc.

 

ive never been to a machine shop that doesnt have an oven to heat up warped cylinder heads and bend then/ tweak them back into spec (on the cam side) and then resurface the combustion chamber side. u should look around at other machine shops.

 

um you should be able to make up some of the difference in lash beingin vtec or not...yous just have to run it a lil looser so the valves will seat properly....im no super machinist but i cant imagine all motor mike is to far off in his statement....

waiting for super machinsit's to chime in....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by all_motor_mike &raquo;</TD></TR><TR><TD CLASS="quote">ive never been to a machine shop that doesnt have an oven to heat up warped cylinder heads and bend then/ tweak them back into spec (on the cam side) and then resurface the combustion chamber side. u should look around at other machine shops.</TD></TR></TABLE>

yeah thats a good idea, got any shops in mind? the few places around here pretty much just do v8 stuff so i'd rather have a shop that deals with dohc heads do it.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drumking15 &raquo;</TD></TR><TR><TD CLASS="quote">um you should be able to make up some of the difference in lash beingin vtec or not...yous just have to run it a lil looser so the valves will seat properly....im no super machinist but i cant imagine all motor mike is to far off in his statement....

waiting for super machinsit's to chime in....</TD></TR></TABLE>

now that I think about that a little harder that may not be an issue. sure the valve lash will change, but it will change on all three rockers so the relationships between them should still come out ok.

so yeah if got this thing straightened enough so that it could be honed I think I would be set. I just don't want to end up with too much money into it cuz by the time I buy new valve seats and valve guides I prolly could've just bought a new head. I'm doing all the work myself as far as cutting and installing the valve seats so that'll save some money, but still.

thanks for the thoughts guys.

 

get dex online and type in machine shop or something around those lines. start calling and asking if they do that kind of service. some of the shops that ive called out here wont do any work on ur head unless the cam side is within specs.

 

Rosko,Before you go and waist a bunch of time and money...take the rockershafts and see if they will slide in EZ.If they won't slide in with almost no pressure,Then put the head in your scrap alum. can Checking the rocker shafts is a bunch easier
than trying to bolt the head to a block and check the cams.
Who ever welded the head added to much material at a time.Thats what makes the head pull is adding material.