Why not?
Ive made a mould and started to lay up some fibreglass and it went really wll until the fibreglass resin went off too early half way through laying
up!
Im convinced that i can make a suitable fibreglass product, but why dont manufacturers make them out of carbon or fibreglass?
Ive only ever seen them in ali or stainless, and i know they could be subject to flame or high temperature but im wondering if its a viable option
before i go and be persistent with my prototype layup!
You rally want to be using epoxy rather than polyester resin.
Claire will probably make you a set in carbon if you ask nicely...
quote:
Originally posted by MakeEverything
.... but why dont manufacturers make them out of carbon or fibreglass?
Ive only ever seen them in ali or stainless, and i know they could be subject to flame or high temperature ....
quote:
Originally posted by RazMan
quote:
Originally posted by MakeEverything
.... but why dont manufacturers make them out of carbon or fibreglass?
Ive only ever seen them in ali or stainless, and i know they could be subject to flame or high temperature ....
erm... I think you may have answered your own question
The entire intake manifold right up to the cylinder head on the KA is plastic.... So composite should not be an issue for you 
Cool, Thanks Tegs.
Ultimately, i was going to go Carbon Fibre, but the fibreglass was at hand and cheap rather than buying a load of Carbon to fail with!!
Ill give it another go if i can remember where i put the mould today!!
Ah but there is plastic and plastic Have you ever seen glass fibre go up in flames? 
quote:
Originally posted by RazMan
Ah but there is plastic and plastic
I cant see any real advantage in using glass over carbon, but i would agree that epoxy would be better over polyester for temperature stability and
flame retardance.
That said, i would be very surprised if it gave you any issues.
Daniel
I thought about this a while back and even got to the stage of making a basic lathe for cutting down wax blocks for the moulds (I was going to use a kind of lost-wax method to make a buck). I was going to go for epoxy GRP. You ideally want a thin trumpet so epoxy glass (or epoxy carbon) is the best option.
...of the carbon variety...no other...before someone accuses me of casting aspercions...
I've seen plenty of carbon trumpets over the years (on high budget race cars), but aluminium is cheaper and easier to volume produce which is why
it's far more common.
Trumpets shouldn't ever get hot enough to melt/burn in an injected setup (carbs can spit back flame so probably best not to use on those).
I'd give Claire the cash rather than DIY as it's an awkward shape to get the weave looking good if you haven't had a lot of
practice.
ETA: QED charge best part of £50 each for theirs (and they don't look as good)
linky
[Edited on 24/5/10 by iank]
it can be done; rover V8
that is EFI so as ^^^ says, no spit back .... but then even with carbs, unless the flames is there long enough to get the material to catch fire, you
are probably ok.
and as ^^^^ said, easier and cheaper to make in aluminium and probablu lighter plus you won't see the blinkiness undr the air fileter anyway.
Glass fibre should be just fine. Glass is less combustible than carbon. Think about it. The benefits of carbon are its tensile strength and its
bling factor. There is no tensile strain on an inlet trumpet.
Fire retardant plastics used in manifolds are usually nylon plastic filled with glass plus a fire retardant additive. You could make yours with
epoxy, glass and if you can get hold of it, a fire retardant additive.
I've been doing complete intakes in carbon fibre since 1989! Before the oem's decided on plastics. And people told me 'it can't be
done, won't work.
It's not a job for the novice though, as many pitfalls are on the way. Take it one step at a time, carefully.
The fibre is of lesser importance than the resin, as trumpets are unstressed, as is the greater part of an inlet manifold.
Cheers,
Nev.