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Cal-look/High Performance => Cal-look => Topic started by: glassback kid on January 22, 2016, 14:17:08 pm



Title: cylinder head is this usable?
Post by: glassback kid on January 22, 2016, 14:17:08 pm
 i have picked up a pair of empi auto linea heads in a job lot of stuff, the heads are cut for 94mm and look like they have been flowed a little, valves i think are 40x35.5. however one of the heads has been dropped and has the first fin smashed off,  it has also taken a small amount of material from the side where the barrel sits with and a little crack on one side of the second fin, So does anyone no if fins can be rewelded on? whether they will run as they are  or not worth the risk?

(http://i232.photobucket.com/albums/ee75/dab72/temporary_86.jpg) (http://s232.photobucket.com/user/dab72/media/temporary_86.jpg.html)
(http://i232.photobucket.com/albums/ee75/dab72/temporary_93.jpg) (http://s232.photobucket.com/user/dab72/media/temporary_93.jpg.html)
(http://i232.photobucket.com/albums/ee75/dab72/temporary_88.jpg) (http://s232.photobucket.com/user/dab72/media/temporary_88.jpg.html)


Title: Re: cylinder head is this usable?
Post by: leec on January 22, 2016, 14:55:52 pm
If you have the piece that has broken off, get it welded. The only offset is how much that will cost/compared to new cylinder head if you can not do it yourself
Lee


Title: Re: cylinder head is this usable?
Post by: Martin S. on January 22, 2016, 18:56:02 pm
You can expect huge problems with polar vortexes forming as the gas expands and regurgitate thru the broken fin area so don't run it!
Just kidding, try it out!  :P


Title: Re: cylinder head is this usable?
Post by: Fiatdude on January 22, 2016, 19:21:56 pm
Just make sure they get a very nice pre-heat into it before they start welding and do a nice slow cool down afterwards and you will be OK


Title: Re: cylinder head is this usable?
Post by: Martin S. on January 22, 2016, 21:35:41 pm
Nothing a little JB Weld can't fix  ::)


Title: Re: cylinder head is this usable?
Post by: glassback kid on January 23, 2016, 08:53:36 am
Thanks for replies think i will have search around for a local alloy welder specialist, i have some old scrap heads so i will cut a fin section of one of them.
with a bit of luck this will solve any regurgitation of them pesky polar vortexes  ;D


Title: Re: cylinder head is this usable?
Post by: DWL_Puavo on January 26, 2016, 13:19:29 pm
I've seen few heads with so deep flycut that they've milled the first cooling fin off so that the cylinder barrel will fit. This of course reduces cooling, but shouldn't be too much of a structural problem.

But as the chamber porting looks good, it has already bigger valves, and I can't see any cracks near spark plug hole even from the larger pictures, it is also my opinion that it's reasonable to fix this head properly.


Title: Re: cylinder head is this usable?
Post by: Martin S. on January 26, 2016, 21:45:41 pm
Interesting about the chamber porting. How do you see it? I looked but I can't see exactly where it was done. Here's an unported chamber for reference.
(http://img.photobucket.com/albums/v415/mschilling/IMG_0407.jpg) (http://smg.photobucket.com/user/mschilling/media/IMG_0407.jpg.html)


Title: Re: cylinder head is this usable?
Post by: DWL_Puavo on January 27, 2016, 09:09:55 am
In Martin's unported (other than the flame channel) heads there is smaller cylinder being used (90,5/92mm I suppose) and also smaller valves. At least some valve unshrouding has been made in glassback kid's heads as the valves are bigger and there's still space around the valves. Area around the spark plug is also smoother. These are easier to notify from the full-size picture in photobucket. Maybe the inlet ports are also a bit larger.

But for the both heads, I would unshroud the inlet valve a bit more from the heads's "center walls" as it's very easy, won't increase the chamber size that much and may provide almost noticeable increase in flow for free. From the glassback kid's heads you can also see the cylinder barrel's edge line, and there's plenty of aluminium just waiting for the grider ;)


Title: Re: cylinder head is this usable?
Post by: Martin S. on January 27, 2016, 18:56:04 pm
Aha, thanks for the clarification. Here are some pics of my turbo heads which were fully ported showing what you are saying about unshrouding the intake valve.
(http://img.photobucket.com/albums/v415/mschilling/IMG_7690.jpg) (http://smg.photobucket.com/user/mschilling/media/IMG_7690.jpg.html)
(http://img.photobucket.com/albums/v415/mschilling/IMG_7704.jpg) (http://smg.photobucket.com/user/mschilling/media/IMG_7704.jpg.html)
(http://img.photobucket.com/albums/v415/mschilling/IMG_8232.jpg) (http://smg.photobucket.com/user/mschilling/media/IMG_8232.jpg.html)


Title: Re: cylinder head is this usable?
Post by: glassback kid on January 27, 2016, 22:28:24 pm
so are we saying assuming that i can get the fins welded, it would be worth while dishing the chamber out a little more, in the places in red on photo
(http://i232.photobucket.com/albums/ee75/dab72/temporary_93_1.jpg) (http://s232.photobucket.com/user/dab72/media/temporary_93_1.jpg.html)


Title: Re: cylinder head is this usable?
Post by: Martin S. on January 28, 2016, 00:51:55 am
Both Puavo and Steve did not unshroud the exhaust valve, just the intake valve. Look at my photos and you will see that Steve left the exhaust side pretty well as-is.


Title: Re: cylinder head is this usable?
Post by: glassback kid on January 28, 2016, 09:16:10 am
Argh ok i get it now just the intake, probably the angle of my photo mine looked a little sharper lip on the exhaust side. Out of interest is there a reason why exhaust should not be done a little


Title: Re: cylinder head is this usable?
Post by: Iryanu on January 29, 2016, 12:48:29 pm
Exhaust, it's just getting forced out round the valve, is it a case of velocity not being the same?

Probably totally wrong. I'll be interested to see the real reason. :D


Title: Re: cylinder head is this usable?
Post by: Martin S. on January 29, 2016, 17:53:09 pm
Steve told me the exhaust ports were good as cast in my 044 heads. They had a nice cobra shape to them. The intake ports were completely wrong he said, and 'they could have saved a pound and a half of aluminum if they cast them right.'  :o