02GF74
|
| posted on 2/11/06 at 02:41 PM |
|
|
DIY cylinder head ... just wondering
just wondering; let's say someone had a cnc milling or even a simple milling machine.
How feasible would it be to make your own cylinder ghead, let's say 16 crossflow.
The tricky part is the internal waterways, oilways and ports so the head is made in 2 halves, upper and lower in order to be able to machine the
internal cavities and then bolted up with a gasket in between.
16 valve crossflow head anyone?
What do you reckon and problems envisaged?
|
|
|
|
|
balidey
|
| posted on 2/11/06 at 03:10 PM |
|
|
 is all i have to say... good luck
|
|
|
MikeR
|
| posted on 2/11/06 at 03:21 PM |
|
|
hasn't it already been done ...........
check out burton's page.
600 quid for an ali 8 valve bare head.
2500 for a bda/bdx 16 valve head.
good luck, you'll have a lot of people jealous (me included).
|
|
|
liam.mccaffrey
|
| posted on 2/11/06 at 03:30 PM |
|
|
best of luck
I think its possbile to do without resorting to casting techniques which is what I think you're getting, but not easy
I would love to have the time to have a go at something like that.
you have me thinking now
|
|
|
StevieB
|
| posted on 2/11/06 at 03:42 PM |
|
|
quote:
Originally posted by zilspeed
Let's take the example of the good old A Series.
BMW K motorcycle head is so compatible in respect of bore centres and head studs that it can be made to fit.
Now - find a head that will fit the xflow in a similar fashion and off you go.
OR
Just fit a zetec complete 
So can you get a bellhousing to go with the A-series, and what gearbox? Presumably an old MG should be pretty much ready to go?
|
|
|
iank
|
| posted on 2/11/06 at 03:53 PM |
|
|
Can fit an MG Midget gearbox, or a series 9 with a bellhousing from Frontline
http://www.mgcars.org.uk/frontline/gearbox.htm
Not as cheap as just shoving in a zetec.
|
|
|
Prez
|
| posted on 2/11/06 at 04:03 PM |
|
|
I would expect the most difficult bit would be getting the port and gas path geometry right, as this is such a performance critical element of engine
design. Modern cylinder head gas flow paths are complex to machine even with fairly specialised equipment, that said, with enough time and patience
anything is possible....
|
|
|
Confused but excited.
|
| posted on 2/11/06 at 04:47 PM |
|
|
quote:
Originally posted by liam.mccaffrey
I would love to have the time to have a go at something like that.
I'd love to have the bloody equipment!
Tell them about the bent treacle edges!
|
|
|
liam.mccaffrey
|
| posted on 2/11/06 at 05:10 PM |
|
|
i bet you could do somthing interesting without cnc stuff, like the old days. could practice converting a single cylinder bike engine to 4 valve or
similar
|
|
|
Volvorsport
|
| posted on 2/11/06 at 05:10 PM |
|
|
didnt the FVA cosworths have ports machined into the head with straight tube , if you machined the valve seat area with enough meat on you could
easily weld some tubes on , hard parts would be lining up cam bearings , valve guides.
TVR speed 12 engine was basically fabricated by hand .
BDA has seperate cam carrier bolted to the actual head , so your not too far away in principle , id pick a more modern bottom end to base it on .
www.dbsmotorsport.co.uk
getting dirty under a bus
|
|
|
liam.mccaffrey
|
| posted on 2/11/06 at 05:12 PM |
|
|
volvo, you aggree though that it is possible to cobble somthing together
|
|
|
DIY Si
|
| posted on 2/11/06 at 05:29 PM |
|
|
With time, it is possible, but getting it to work is perhaps the hard part. What about choice of cams? Would any/most 4 valve cams do, or would the
timing have to be very engine specific?
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
StevieB
|
| posted on 2/11/06 at 06:10 PM |
|
|
quote:
Originally posted by Volvorsport
TVR speed 12 engine was basically fabricated by hand .
And engines don't get much more impressive than that one!
So powerful, they had to cut it in half for road use
|
|
|
Volvorsport
|
| posted on 2/11/06 at 06:19 PM |
|
|
itd be interesting for a project , altho i reckon i can get a 8v to flow the same .
theres a B20 nocking around (pushrod 8v) at 236 hp , from carefull port work (epoxy filling) etc .
www.dbsmotorsport.co.uk
getting dirty under a bus
|
|
|
JackNco
|
| posted on 2/11/06 at 07:43 PM |
|
|
ok ive read the whole thread and everyone seems to have missed a very important question here...
WHY HE HELL WOULD YOU BOTHER!!!!
surely it would be easier, less time consuming and nearly as cheap to just swap out the ending for a 16v engine?
John
Some people are worried about the difference between right and wrong. I'm worried about the difference between wrong and fun.
O'Rourke, P.J. (1989), Holidays in hell. London (Picador)
|
|
|
ettore bugatti
|
| posted on 2/11/06 at 08:10 PM |
|
|
In dutch, but pictures says it all.
http://home.tiscali.nl/modelengines/36ccviercilinder/de_cilinderkop.htm
Apfelbeck wrote a book on constructing your own cylinder head
http://www.apfelbeck.nl/
|
|
|
DIY Si
|
| posted on 2/11/06 at 08:39 PM |
|
|
Good point raised by Volvo, if you get the ports roughly right, you can always "flow" them with epoxy resin to put the necessary radii in
place.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
MikeRJ
|
| posted on 2/11/06 at 09:32 PM |
|
|
quote:
Originally posted by DIY Si
Good point raised by Volvo, if you get the ports roughly right, you can always "flow" them with epoxy resin to put the necessary radii in
place.
Not the exhaust ports though, unless there is some miracle epoxy that can take that kind of temperature.
|
|
|
DIY Si
|
| posted on 2/11/06 at 09:38 PM |
|
|
Fair point that! But if yu do it right, you could probably make the exhaust port easier/straighter than the inlet, and have less shaping to do.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
liam.mccaffrey
|
| posted on 2/11/06 at 09:39 PM |
|
|
quote:
Originally posted by JackNco
WHY HE HELL WOULD YOU BOTHER!!!!
that is the whole point, you don't need to, and its probably not the best/cheapest/easiest thing to do.
but i bet if i spent the next year building a cylinder head i'd learn a shed load more than any book could tell me
|
|
|
DIY Si
|
| posted on 2/11/06 at 09:48 PM |
|
|
And think of the bragging rights! Did you make that car? Yup and half the engine, from scratch, with out any training!
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
liam.mccaffrey
|
| posted on 2/11/06 at 10:42 PM |
|
|
biggest braggin rights ever
|
|
|
JackNco
|
| posted on 3/11/06 at 12:03 AM |
|
|
lol ok bragging rights IF it works and u get any improvement in power. f it just blows up then i wouldn't be bragging about it. im the same
with computers *why did you do that* * because i could* but that just seems like SOOOOO much effort for no reason.
John
Some people are worried about the difference between right and wrong. I'm worried about the difference between wrong and fun.
O'Rourke, P.J. (1989), Holidays in hell. London (Picador)
|
|
|
Marcus
|
| posted on 3/11/06 at 08:43 AM |
|
|
quote:
*why did you do that* * because i could* but that just seems like SOOOOO much effort for no reason.
That, to me, is what Locosting is all about. Not because it's economically viable, not because it's the easy route. It's why I built
my chassis (twice) and didn't buy one.
It's the reason I modified other parts rather than buy off the shelf.
It's the reason my car only cost £1500 to put on the road rather than 6-7k.
That's why, when people ask "is it a Caterham or an original Lotus" I can just grin and say nope!
It's the Locost way!
Marcus
Because kits are for girls!!
|
|
|
Syd Bridge
|
| posted on 3/11/06 at 09:00 AM |
|
|
It would be far easier to make some patterns and cast exactly what you want.
Sand cast inside a closed box with a vacuum pump on, so no porosity whatsoever.
Cheers,
Syd. 
|
|
|
