Inlet manifolds for a V8

I have made some inlet manifolds in Carbonfill for my Ford V8 now I can use 4 Weber 40dcoes and see if this makes it fly or die

Won't that dissolve when the gasoline hits it?
Won't it melt when the engine heats up?

It might be better to 3D print a pattern, cast in aluminum, then machine to final tolerances...

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

No it does not dissovle in gasoline ,you can buy carbon fibre tanks for your car and motorcycle !

And no it does not melt ,,,it will at 265 degrees but if thats the case then so will the engine !

Carbon fiber fuel tanks are made from CF and epoxy, not thermoplastic. They probably also add a liner. I think you'd better test a print by putting it in gasoline and see what happens. The material doesn't have to melt- all it has to do is soften or swell. Gasoline and heat (plus the weight of a carburetor hanging off it) is a pretty tough combo for any plastic to survive.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

The first test part is still in a Container of gasoline , ist been there for 2 weeks still as solid as ever ! And as for the weight Thing, people make bike frames etc out of the same stuff and that dont bend or break ,you just have to design it properly . Have you tried this stuff or is it all theory ? And as for making moulds I do that as well , but ist cool to build These manifolds in my back room and see it all come together .The reason behind rep rap, Mendal the first one ? Is to do what you want go where no one has tried before ,and if it dont work , try again , all in your own back Yard :And on my German Rep Rap Protos V3 heaverly modified as the original is crap .

@zurferjoe. Good job man.

As an ex old time automotive engineer, I've spent many hours setting up twin choke webbers in various configurations. The old time Ferrari V12s had 6 of them.

Completely off topic but as a rule of thumb, use the formula Vn/40 to select what size carb to use. Where V is volume in cc (of a single cylinder), and n is the max engine rpm. A lot of people fall into the trap of fitting carburettors which are just too big for the engine which results in too low an airflow rate for them to ever work properly. To find what choke (venturi) size to fit use Vn/50.

You probably already know that the inner surface of your manifolds should be as smooth and polished as possible. You'll get more torque out of the engine with the longest inlet tracts that you can package.

The most important thing to check is that they are not at all porous and you have a really good seal between the manifold and cylinder head, as well as between the cylinder head and carburettor. This can be a huge problem with castings. You don't want any air getting into the engine that doesn't go through the carburettors.

Finally, you may run into problems with fuel starvation. It's caused by vibration making the fuel in the float chambers "frothy" and it's worse the further the carburettor is mounted away from the centre line of the engine. The fix is to mount the carbs using flexible mounts (big fat "O" rings on the face, and springs and lock nuts on the studs).

HTH

Thank you for that ! Wow I learnt more from this then all the other stuff I have read on Internet ! I have a 13" middle of carb to valve stem length .And I will follow your advice .Will Keep updating on this Project , as It seems no one else has done it before .As for the smooth bores in the manifolds they are polished ,inside and out , carbon surfaces are perfect for this , and then I will get them chromed ! Oh yes you can !!! Firms all over do this every day , you have These items , chromed plastic all over and in you car etc etc .

I haven't tried CF filament in my printer, but I did design and build a bike from CF cloth and epoxy about 10 years ago, which I still ride...

See: [mark.rehorst.com]

I don't know what sort of plastic they use for the CF filament which is why I question its use in this application. I used ABS for a motor mount in my printer and found that after about a year of operation, the heat from the motor and the belt tension caused the mount to distort even though the operating temperature was no where near the glass transition of ABS.

Good luck with it. It's a great design and application if it works. I hope it does what you need.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

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zurferjoe
Thank you for that ! Wow I learnt more from this then all the other stuff I have read on Internet ! I have a 13" middle of carb to valve stem length .And I will follow your advice .Will Keep updating on this Project , as It seems no one else has done it before .As for the smooth bores in the manifolds they are polished ,inside and out , carbon surfaces are perfect for this , and then I will get them chromed ! Oh yes you can !!! Firms all over do this every day , you have These items , chromed plastic all over and in you car etc etc .

Good stuff. Nice to know that we old 60 something's still have our uses. Chroming the insides might be overkill. You need to be absolutely sure that none of it will flake off as there are some very tiny holes inside the carbs which you don't want to get blocked. By the way, chroming plastics and other materials is nothing new - I saw a chrome plated dog turd in the 80s.

You mean "WE " 60 plus guys !! Im in my second year of retirement !! I just dont think old !! The older you get the faster you where !!

What filament are you using? I'm pretty impressed that this might actually work. Keep us updated on the progress!

Hi there , I buy it here in Germany from Filament World ,I use the 2.85 Filament ,the 1.75 mm seems to break to easy on on instalation . Its called "Form Futura Carbonfil" ,Carbon, great to use and very stable when you print . Im down to .70 feedin on the Extruder. 265 degrees exruder temp and 65 bed temp , which I Switch off (the heated bed )after the raft has been formed . I use Simplfy 3D and the rest is easy !!!!! Hope this all helps all the best Harry

Apparently the carrier is their HDglass which they describe as "modified PETG". I've heard of plastic inlet manifolds becoming more popular (and occasionally troublesome), but I don't know what plastics they use. Fingers crossed these hold up - sure looks great, but it's a pretty tough environment in there!

Nice job man. I hope it holds up. Don't forget to buy an air flow meter to sync your carbs.
[zcardepot.com]

Making a Flow meter on my Rep Rap !! Na just kidding

A piece of tube and well trained ear works just as well as a flow meter.

I have just printed some CarbonFiber bellmouths for my 40 DCOE Webers , not bad eh !!

That looks sweet!

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deckingman
A piece of tube and well trained ear works just as well as a flow meter.

Ah, an old (school) fart eh?

Here are the Carbonfil20 inlet manifolds on my Ford Flathead Motor and Webers with Bellmouths also Rep Rap Carbonfil20 Looks cool and I hope it gets the old Motor churning out a bit more BHP !!

Beautiful!

And again this time showing the Carbonfil bellmouths ! cool eh , hope it goes as fast as it Looks

That filament has a glass transition temp of only 85*C. That is going to be interesting to see when it gets warm -- especially with the weight of those carbs hanging on them.

Yep, Tom Sanladerer just did a review of a Carbon Fiber PLA and was able to distort it greatly after dumping boiling water on it.

https://youtu.be/-Z3Nq4hwKgs

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FA-MAS
Yep, Tom Sanladerer just did a review of a Carbon Fiber PLA and was able to distort it greatly after dumping boiling water on it.

https://youtu.be/-Z3Nq4hwKgs

I wonder if that is why we haven't heard from the OP recently.

So everybody wants the manifolds !! But not in Carbon PLA !! So as suggested in this Forum make Patterns and then make sand forms and then cast them !! A lot of bloody work !! Hope it turns out as good as the 3 D Picture ! Will Keep you posted !

Edited 2 time(s). Last edit at 01/23/2017 12:13PM by zurferjoe.

Awesome! Glad you're getting interest in the parts. Please let us see how it comes out, and get someone to take photos or video during the casting process!

Thank you !! When it happens I buy the beer !!!!!

Hi all you 3D priters , heres my update on the V8 manifold casting boxes Im printing out on my much modified German Rep Rap Protus 3 . They are large casting boxes , altogether 18 pieces and this is a Picture of one Piece .Keep you up to date when I have cast the first Sand moulds !!

Awesome! Now that is serious