if i used metal on the flanges and made the rest of a EFI manifold from fiberglass, would it work? i was just thinking... theres a specific shape i want the ports... a way i want them necking down to the headport size for good volicity... even if i dont get it 100% perfect, it would be pretty darn good... now i could make a plug of exactly what i want that air to flow in.. the inside of the runner basicly... then run some fiberglass over it.... and i have a tube the right shape. mount 8 tubes to the flange and build up some material for strength..... then have them all meet in a plenum..... is there any reason this couldnt work? is there a reason i havent seen any other V8 fiberglass intakes? i know LS1s and other motors have composite intakes, but they generally arnt fiberglass. i have seen some fiberglass plenums for inline motors, but they're all exotics or europeian cars.... ideas? comments?

i think it would work . I mean they have those new lsx intake mainfolds for the ls1 that are compostie . They actually give some hp bc of the heat dissapation.

i posted for this to be clear, but i'll say it again..


the LS1 manifold is NOT fiberglass.. its is a diffrent composite then what i would be using.



anyone know of any sites or webpages where fiberglass was used and how it worked out??

fiberglass wouldnt work. because it would melt before long. if u coated it with some kind of hi temp coating or something of that nature it might work.
good luck and tell us how it goes

ok, thats what i was wondering..


so where can i get some resin that can withstand constant 300*??

summit mayb
a welding shop

somthing like this should work: http://resinservices-reklein.com/laminate/fhtl3869.htm

no its not high enuff.
290 is nothing.
at least 500 is what your gonna need.

It can be done by using carbonfiber and e special high heat deflecting temp epoxy resin.

Actually I saw an article in a Swedish paper about making a CF intake for a Volvo S40 that where used in the STCC racing series.

The guy however, used prepreg carbonfiber and an "enclave?" to heat and pressure curing it...

The intake flange against the head had to manage a temp of up to 130-150 celsius.

The intake runners had aluminum injector bungs epoxied into them. That was the only metal used...

But then again, this sort of intake can be built to last one or a few races - you would probably like to make yours last a lot longer.

I made a small 3D studio job of how a composite intake could look like, even before I read the article above..

http://aldengard.lixom.nu/gallery/in...intake_carbon1

But I gave up when I realized that I have to cure the resin in an even higher temp than the resulting HDT (Heat deflecting temp.). The HDT is a point where the material starts to "die"...

/Anders

yea... what im thinking is somewhat similar to what you made there.

i already made one intake manifold, but i sold it because i was offered a huge amount of cash for it.


that one was made of steel... im not doing that again, too heavy..

if i make one out of metal again, im going to convert my MIG for alum first.....

try it with polymer

Travis do a search over here.
http://www.fibreglast.com

http://www.fibreglast.com/phpBB2/ind...0e340842924966

Mrdude.. the reason they aren't made out of fiberglass, is because the resin cannot withstand the heat. There are some resins that can hold up better to flammability, but not to the point where they can resist the amounts of heat that a manifold has to cope with, and the fuel passing through it. Also, I doubt you could do a better job at analyzing the airflow needs of your engine, its not that easy, and you would need a flowbench to test it, and match it to your heads, cam, headers, etc. it's not just a matter of flowing the most air. Also, I wouldn't like to see what happens if your engine backfires....

The composite parts used in engines (formula 1 etc.) are used with carbon fiber that comes "pre-impregnated" (called pre-preg) with special mixtures of resins. There are hundreds of combinations of fibers weaves and resins depending on the intended use. Pre-pregs also need to be stored in a refrigerator, to prevent the resins from kicking-in and hardening.

Then , it is oven cured in an "autoclave" which is an oven that not only heats, but applies pressure (think of it as a big pressure cooker, minus the water) and applies negative pressure to a plastic layer located right atop the part, to ensure uniform pressure against the mold.

The controlled baking times and resin mixtures (the recipe, so to speak) are the secrets that manufacturers keep closely guarded, although nowadays some info has leaked to the amateur builders.

So, to make it short, all composites are not created equal.

you narrowed it down to my question without answering it.

what resin do i need?
the fiberglass itself will withstand the heat and fuel no prob

its finding a high temp resin thats fuel tolerant.


as for the actual design, thats not a major issue. im not trying to make a fully tweeked race manifold.. i just want to make a simple, untuned large plenum setup... probly one that can withstand mild boost.



before i do the intake manifold, im thinking of making a intake tract for the blower....

i made a radiator cover for a motorcross bike yesterday.. im thinking of possibly just making a few neat things... like covers and such for underhood.


the problem is... i need somthing that can take the heat, vibration, and petrolem based chemicals underhood.

I don't think you will find any. The heat resistant resins (polyester and epoxy) you will find, are usually used for racecar bodies or kit car firewalls, not for direct use on an engine. If you had an industrial setup, the big companies that sell to the aerospace manufacturers have the materials, but of course they sell in quantity, not such small amounts.

If you want to apply even mild boost, that's another problem, I think you will have big leaks and distortion.

I have made some underhood fiberglass components, such as scoops, adapters for aftermarket filters to MAF sensors, etc. but I have used aluminum sheetmetal as the core material for areas that need threaded inserts and such.

And you want to mount a blower on top of that? just think of the weight, vibration, and the tension force and torque that the blower belt will exert on the composite manifold. I don't think it would be such a good idea, better get an aluminum manifold, and in case you want more airflow, you can port it or extrude hone it.

If you want to experiment with airflow, a manifold made with sheetmetal would give you a chance to do that. If the idea is weight savings... I don't think it would be worth the effort and possible problems, there's other ways to lighten up the car.

just my $.02.

i wouldnt put the blower on top of the manifold.. lol.

the concept was intresting... one of my friends came up with it.

theres no place for my eaton underhood except on top of the motor....
rather then have the blower on the manifold, what if we pushed the manifold over?

so we came up with this funky lil design that has a few hard to make curves in it...

i came up with this idea.... we make the blower mount and most of the manifold from alum like we've been doing, but we make a skeleton of the plenum and parts of the runners from alum.
then using a foam core, we make a fiberglass manifold. this gives us the shaping flexability we need, and the composite structure will withstand the boost..

i realise it wont be lighter... heck we arnt even bagging it, but it should hold the boost, and fit.

since the blower isnt on the manifold, it can now blow out to a discharge into the intercooler, across the front of the car, and back into the manifold from the front.


long concept, we'll probly never do it, but i would like to make some underhood stuff... if for no reason other then i can.

btw, we used machined metal barbs with alot of surface area to cling to for our threaded inserts.

There was something I saw on the Discovery channel that might work even better than fiberglass, and would hold up to the heat. The only problem is getting enough heat to liquify the aluminum in the first place.

But here's the idea:

Get a large square of styrofoam and carve the design exactly as you want it.

Then place it inside a large container of sand, being careful not to bury it to deep, but completely covering the styrofoam mold. I would place some kind of steel tube or pipe in the sand leading to the styrofoam mold, however if the sand is loose enough the liquid aluminum would drain to the mold on it's own. This part was a little cloudy to me.

Next pour the liquified aluminum in the tube. The aluminum will then melt the styrofoam.

Give it time to cool down and harden.

Once it's cool enough to work with, you can take a die grinder and a dremal tool to it to finish it with a polished look.

Cast aluminum is stronger thaen fiberglass and lighter than steel. You would win in both areas.

This is just an idea. Hope it helps you out.

It'll take some SERIOUS heat to melt enough aluminum to make an intake manifold, but that'd be damn cool to be able to make your own cast aluminum parts

so in otherwords..... cast my own alum intake manifold? lol


if it was that easy to cast stuff, everyone would do it

Check out these websites. It's not hard. And it can be done in a cost effective manner as well in your own back yard.
http://www.backyardmetalcasting.com/index.html
http://freespace.virgin.net/foundry.fopars/
It would only take 660 C/1220 F to melt Aluminum. These websites show you how to create a furnace at home for very little money (some items you may already have), that will heat up to approx. 1200 C/2192 F.
I think I will start saving my aluminum cans.

Hey dude I was just reading your post on the intake manifold fab and I was thinking that you could do it for sure. Just make the flanges out of metal that go to the intake ports and make them resemble a intake gasket but leave the back water passages closed. Then cut a flat piece of metal out for the bottom to cover the lifter valley and weld it to the side flanges at the edges. cut a hole for the distributor and weld a bolt onto the flat metal base for the distributor hold down. Next get a remote thermostat housing and find a way to connect it to the front openings of the flanges where the water ports are. Now that you have the bottom part of the motor sealed you can try and fine the same material used for carb heat spacers and cut out your own port heat spacers to isolate the lower manifold from the upper one that will be made out of fibergalss. Then tap the new lower for some tiny screws to hold the upper to the lower, you could probably use TPI runner screws. Like this....

My brain is too tired for this right now, but...

I was recently reading about Dick and Burt Rutan, builders of the voyager airplane that circumnavigated the globe without refuling and contestants in the X project, a competition to privately build a manned rocket. They are extremely adept with composites. I can't remember the name of their company but a quick search should help. I wouldn't be surprised if they were willing to give you some "High Tech" options for your project.

That said you might want to look at making your own plastic/composite manifold maybe using a combination of vacum moulding and machining.

If you search on aircraft composites you might find what your looking for, aircraft spruce comes to mind, their catalog is a hotrodders necessity IMHO

Wouldn't the fiberglass be rough and hinder flow anyways?

it can be any shape you want... from totally glass smooth, to a very rough texture.

where the fuel is suspended, you want some roughness to the texture of it, but for most of the manifold, semi smooth is idea... perfectly smooth makes the air "stick" to it and it flows diffrently.



in anycase, id probly make a plug of what i want the inner runners to look like so they'll be smooth and all taper the same.

right, but how are you gonna smooth the inside out?

the plug is smooth so it'll be smooth to begin with.

but in anycase..... who says it has to be one piece?

Just because the plug is smooth doesnt mean the inside of the fiberglass will be too. If you've ever worked with glass before you know that it's still rough even when using a mold. A 2 piece design might work, that way you can access the inside to smooth it out, but how do you plan on doing that?

I think a good way to smooth out the inside would be to use a small dremel type tool with the snake attachment with a small sandstone on the end of it. You could use one of those with a one peice design or a multi piece design. The multi piece design could be multiple pieces until you get the inside smooth as you want it, then you could seal it with a thinner outer glass shell that would be used for a finished look and to keep it sealed air tight.

i should phrase that as "smooth enough"

i dont want perfectly polished smooth walls.

That's going to be a lot of cans lol... they melt down to nothing really. Fun to watch them melt though

You can always make a intake mold out of styrofoam, carve it to the shape you wish, cover in fiberglass, with correct resin, let cure, then disolve the stryo with acetone. A lot of work, but it can be done. BW

Check out http://www.fibreglast.com for resins, tech info, all that for your fiberglass and carbon fiber work. I bet they've got something that can be used. Then come back here, and tell us how it went

Andris

I take it you mised my links say about a dozen or so posts up.
lol.

I have a 90% finished glass superram plenum I did but never got around to finishing it.

i may be stuck to making some runners from metal, and then making the plenum from glass...

i got this stuff from a local boat repair shop that i was told is good for 300*

i made a small sample and heated it to 270 and held it there for a hour.... it started to disfigure

it could have only been because its one layer, sometime later, i'll try making a thicker one and do the same thing....

TPI-383 - Doh! I excited about the link, I forgot, he he he.

MrDude - Painting it with a heat barrier would probably help keep the heat out of the part itself, and I'm thinking the top of the heads and valley of the block wouldn't be any hotter than the coolant temp.

I tell this exact same thing to people who ask me How powdercoating holds up on a intake. Esp when They dont know anything and I say well its cured at 350* they say Well a Block gets hotter then that......

hopefully, my coolent temp will never get that hot.

however, if it does, i dont want to be forced to go thru the work of making one again.

I just finished taking a polemers class in college and i was going to make a few small parts that would be in the engine compartment and the professor gave me a few ideas for doing such things....
1. if gas is going to be flowing within it use a vacum mold and create a HDPE (high density poly ethelyn) liner and then reinforce it using fiberglass on the outside. The HDPE is extremely smooth and petroleum resistant when using high qualtiy product.
2. most aero space technology resins are designed for extream heat created at re-entry

I guess if you made a vacume mold of the intake runners and then reinforced the runners with the fiberglass it would work I would think that CF would work better for pressure because it wouldn't flex as much as the Fiberglass.

I hope that helps

Whazzit? New polymer resin? Whare can one acquire said resin? Would a marine supply have it or is it something you have to specialy order? Is it a type of vinyl ester resin?
Why vacuum bag it? Can't I just treat it like a gel coat and then build it up from there? Say maybe make a foam core plug, coat it then start laying up the fabric layers from there?

i demand pictures.

Im speaking of this only thru theory I have not done this HDPE is the plastic they use to line gastanks its also known as the poor mans teflon and the plastic used in soda bottles. you would vacum form the intake runners so this way you could have an almost perfect line up then fiberglass over it once the fiberglass cures you would pull the HDPE liner out.
I would guess if you wants such resins you would have to find someone to specialty order them from. Like I said I have not done such things but through my studies this is how I would say it has to be done

Aren't gallon milk jugs HDPE?

yes they are

if you just melt aluminium and you dont skim the crap off the top then you will have alot of contaminates in the casting, plus you will need to add some alloys to the molten to make it more durable, you wouldnt want a deadsoft manifold, aluminium cans are a bad choice, scrap-barstock would be a better choice.

On a side note a Fiberglass or composite manifold would be my first choice for a manifold.