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steel vs aluminum inlet manifold
oadamo - 23/8/10 at 12:11 PM

ive seen a lot of custom manifolds made from aluminum on turbo motors but what is the real benifits vs steel. i no theres the weight factor but i would of thought you could use a thin gauge steel vs 3-4mm aluminum and the weight would be about the same. but then theres the heat factor ?? is there any real problem.
is there anyone on here running a steel inlet are you seeing any problems.
adam

Howlor - 23/8/10 at 12:40 PM

Alot of OE engines run a plastic manifold so I would have thought that heat was no issue.

Steve

02GF74 - 23/8/10 at 01:02 PM

only reason I can think of is that maybe corrosion (read rust), if using mild steel, may be an issue.

air contains moisture (read water) so given enough time, will corrode the surface.

coozer - 23/8/10 at 01:07 PM

I would say its just much easier for the home builder to fab up something out of steel. Not every one has a tig for welding ali...

omega0684 - 23/8/10 at 01:43 PM

have you ever tried porting steel!

Cast ali and then port to match inlets for more efficient breathability i say

Bluemoon - 23/8/10 at 03:12 PM

quote:
Originally posted by omega0684
have you ever tried porting steel!

Cast ali and then port to match inlets for more efficient breathability i say


True but you would fabricate it nothing to stop you matching up the ports by design, all be it more difficult.

The ones I have seen (ali or steel) are just pipes welded to a plates..

Casting a ali inlet at home is not that DIY an approach (it could be done but would be a lot of efffort, you would have to make your own forge! but you would also need a mill to finish it off!).

tonym - 23/8/10 at 03:53 PM

Icing up can be a problem with steel.

trikerneil - 23/8/10 at 06:26 PM

quote:
Originally posted by tonym
Icing up can be a problem with steel.


Any idea why?

I'm halfway through a steel inlet manifold build myself

Neil

Bluemoon - 24/8/10 at 12:28 PM

quote:
Originally posted by trikerneil
quote:
Originally posted by tonym
Icing up can be a problem with steel.


Any idea why?

I'm halfway through a steel inlet manifold build myself

Neil


Ali is a much better conductor (i.e. it will be heated by the head I guess). If you had a problem I suppose you could wrap some 8mm micro bore pipe into the cooling system to warm them up a bit maybe with a valve so you can set the amount of extra heat (in fact a electric fiesta heater valve would be perfect, you could have a switch on the dash)?

lotusmadandy - 24/8/10 at 02:29 PM

I have been running a steel inlet for 2 years now with zx9r carbs and have no corrosion heat or icing problems.

Andy

rusty nuts - 24/8/10 at 06:19 PM

I made my inlet manifold from a piece of 12 mm ally plate and off cuts that I already had . Cutting to shape was easy using a woodworking coping saw and plenty of cutting fluid

FASTdan - 25/8/10 at 09:04 AM

I have experienced massive icing on stainless steel inlet (pinto on ZX9's). Mid winter, there was literally a frost coating the headers - quite unbelievable to see.

Whereas as has been mentioned alu soaks up heat far better and retains it for much longer.

Bluemoon - 25/8/10 at 12:43 PM

quote:
Originally posted by FASTdan
I have experienced massive icing on stainless steel inlet (pinto on ZX9's).


... And stainless steel is a worse conductor than steel so icing would be worse still.