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Welding inlet manifold
ned - 21/10/03 at 11:41 AM

I've been considering my options for an inlet manifold for my 8v vx to run my webers. The cheapest price I have found for a new manifold is £135! I'm not really wanting to shed out this sort of money, when the 8v is temporary until i get the 16v sorted.

I've found inlet manifolds for the production cars for £25 but they are for the engine mounted at 7 dgrees, not upright.

Question is, if I get a second hand manifold, cut and shut it is there anyone who'd be able or willing to weld it up for me? I assume the inlet castings are aluminium? Someone nearby would be preferred but if not I'll pay all postage and costs etc etc.

It must be cheaper doing this than shedding out on a new one?

thanks,

Ned.


A Badger - 21/10/03 at 12:08 PM

Ned,

What difference does the 7 degrees make to the manifold. Can't you just take up the difference with the exhaust coupling?

Or since they are designed for FWD the output is now pointing forward rather than backward?

Your other option is to make up a tubular one - manifold blanks are quite cheap and a bit of cunning work with standard tubes should produce something better than a restrictive standard affair.

Andrew


ned - 21/10/03 at 12:11 PM

Andrew,

not quite sure what you mean. I'm talking about the inlet manifold for mounting the weber 45's to the engine. if i use the standard production type @ 7 degrees my carbs would not be level and hence my float chambers on the piss, which i'm guessing would mean the carbs wouldn't work to well, if at all.

cheers,

Ned.


DaveFJ - 21/10/03 at 12:17 PM

Tiger website is offering the manifold for £98 + vat - not much cheaper but there you go... (would save £20)


A Badger - 21/10/03 at 12:23 PM

Sorry Ned, being dim I read inlet as Exhaust Doh!!

Yes the 7 degrees would make a big difference.

I guess that welding it would be the easy bit, there's going to be plently of work to ensure that the flow isn't reduced by the cut and shut work.

The other issue is length (as ever) I guess that there is plenty of room in a FWD installation for a reasonable length (100-150mm) of inlet to give good mid range. For the Pinto you can buy short manifolds to allow it to fit better in a Locost.

Andrew


ned - 21/10/03 at 12:27 PM

I'm not too bothered about the smoothness of the porting as it's only a temporary engine to get the car running with all the bit being interchangable to the 16v.

Point taken about length though, as i guess this'll affect the hole cut in the bonnet too!

cheers,

Ned.

protofj,

i can't see a vauxhall manifold on tigers site, they do an ohc engine one, but i assume this is for a ford xflow or pinto.

[Edited on 21/10/03 by ned]


Surrey Dave - 21/10/03 at 12:45 PM

If it's only 7 degrees is it not possible to machine the head mating face of the manifold at a slight angle to sort it.
It would depend on how much meat there is on the casting obviously.
You would probably only have to remove 1 or 2 mm from one side ( top or bottom) and let the fixing studs work at a slight angle.

In true 'Locost' fashion you could even file or grind it yourself and then face it of on a flat block or glass with emery.


timf - 21/10/03 at 12:54 PM

also if theres not enough meat on one of the flanges mill a bit off both.

an engine machine shop could mill it for you on the head facing machine.


Ben_Copeland - 21/10/03 at 12:56 PM

That would most likely weaken the vauxhall manifold to the point of breaking, when you do the nuts up ! They are fragile even in unmolested form!!

I was thinking about doing this too. (probably where ned got the idea)

I'm gonna cut out the shape into thick steel and then weld the tubes on... its getting all the right shapes and lengths, which is the difficult bit !

[Edited on 21/10/03 by Ben_Copeland]


Surrey Dave - 21/10/03 at 01:11 PM

Make up a sandwich plate to go between manifold and head, and have it machined at the applicable angle.

6mm thick down to 5mm whatever it takes.
fit it between 2 inlet gaskets.............


ned - 21/10/03 at 01:37 PM

thanks for the help and suggestions.

Shame no one can weld it, i thought it'd be easy to cut out the required amount and get it welded back together.

thanks,

Ned.


rell - 21/10/03 at 01:45 PM

make all the cuts you need and then take it to the local fab shop and slip the man a tener jobs a good one.
to weld alli you need a tig welder with ac curent on it


DaveFJ - 21/10/03 at 01:51 PM

quote:
Originally posted by ned

i can't see a vauxhall manifold on tigers site, they do an ohc engine one, but i assume this is for a ford xflow or pinto.

[Edited on 21/10/03 by ned]


sorry my mistake - got confused with zetec - duh


Surrey Dave - 21/10/03 at 02:07 PM

Could be a yellow pages job...

There must be someone near you who does aluminium welding............


Mark Allanson - 21/10/03 at 07:06 PM

Ned, do you mean something like this? I know this was done to shorten the plenum chamber but you could drill it to match webers? Rescued attachment Plenum12.jpg
Rescued attachment Plenum12.jpg


Northy - 21/10/03 at 07:10 PM

Wouldn't it distort it?


rell - 21/10/03 at 08:03 PM

what you need to sort this out

a flat bed (use a piece of glass and be carfull)

some engineering blue

a file

and a scraper

but you should be ok if the plate is a thick enough and don't put to much heat in the work when welding it also clamp it to a flat surface

if your no good with a file go to the local machine shop and have the thing ground flat but i will tell you now it won't be cheep


Mark Allanson - 21/10/03 at 08:15 PM

As long as your cut is dead level and you don't get too excessive with the amps you should have no problems. I dont have an AC tig so it was done at lunchtime at a local engineering company for a couple of pints of Butcombe!

Clamping it down is a waste of time because if you build in any distortion, it will be stored in the work until you unclamp it, the it will spring out of the clamps.


ned - 23/10/03 at 09:25 AM

this is the manifold in question i'm going to buy (£30), i've finally got a pic of it! as i said, i need to make it tilt up 7 degrees more in effect. could anyone comment on the thickness of the material for adding/taking some off or cut & welding it?

thanks...

Ned.



The top pic is upside down, this is how it would sit on the engine..



[Edited on 23/10/03 by ned]


Northy - 23/10/03 at 10:26 PM

That looks the same as mine! £30! Mine cost a f*cking fortune! Are you sure its angled, don't think mine is! Too cold to go into the garage and look now, will look tommorrow.

Ned, new suggestion, cant you tilt the engine over a bit so the carbs sit level?

Cheers

(Just got back from seeing Chubby Brown)

[Edited on 23/10/03 by Northy]


Ben_Copeland - 24/10/03 at 08:02 AM

not with the new bell housing he just bought he can't lol


ned - 24/10/03 at 08:58 AM

As I said £135+ for a new one if i can adapt this one i'll be happy until i get the 16v in. The bellhousing is for an upright engine, don't think the 16v would fit under the bonnet at an angle...

I've had a message from someone willing to weld it up for me if i supply it to him cut and glued together he'll zip round with a tig..

marvellous...

Ned.


Ben_Copeland - 24/10/03 at 09:03 AM

Excellent smithers............... you just have to not destroy it, when you start cutting it about !

p.s. maybe that kind person will offer to do mine, when i get round to it


ned - 24/10/03 at 09:08 AM

quote:

p.s. maybe that kind person will offer to do mine, when i get round to it


nah, probably not


Northy - 26/10/03 at 05:57 PM

Looks like my carbs are at an angle, but I'm not going to worry about it. I think the engine could be leant over a touch without affecting anything.

Ned, new photos uploaded into my photo archive Rescued attachment Carb Angle.jpg
Rescued attachment Carb Angle.jpg


MikeRJ - 26/10/03 at 06:40 PM

quote:
Originally posted by rell
to weld alli you need a tig welder with ac curent on it


If you aren't concerned about the ultimate in weld strength/neatness you can MIG aluminium perfectly well.


ned - 28/10/03 at 09:53 AM

Northy,

Thanks for the pics update, i have a load from the weekend that'll be going up on my site soon, may post some of them here to illustrate the point...

cheers,

Ned.


ned - 28/10/03 at 05:13 PM

Northy,

It looks like your webers are tilted upwards slightly, mine would be tilted down with the manifold as it is.

To save me posting a load of large pics please check my website for loads of pics.

pics at bottom of this page:
http://www.locostbuilders.co.uk/users/ned/build/engineinstall/index.htm

thanks,

Ned.


Northy - 28/10/03 at 06:22 PM

WTF!

Yes, my carbs angle upwards slightly.

Your inlet manifold looks exactly the same as mine. My guess is they cast them and grind them to what they need.

I'd get one or both of the faces altered if I were you.

Why can't you tilt the engine slightly? It wouldn't take much, just add a spacer under one of the engine mounts.

Cheers


Ben_Copeland - 28/10/03 at 11:51 PM

That would tilt the gearbox too.... meaning the gearshift would be at a dodgy angle


dmottaway - 29/10/03 at 02:47 AM

if you are not in a big hurry, you might want to look at

manifolds.co.za


prices are very reasonable, but located in S. Africa. Shipping may ruin the deal.

dave


Northy - 29/10/03 at 08:03 AM

It would only tilt it slightly! The gearstick is going to be too long anyway, so will need cutting, shortening and welding. Why not weld it at a bit of an angle to overcome it?

He is only supposed to be using this till the 16 Valver goes in anyway

Cheers


ned - 29/10/03 at 09:40 AM

might then have probs with the sump/baffling and gearbox mounts would have to be fiddled about. I'm thinking along the lines of getting the manifold to engine face machined to the correct angle, either that or a sandwich plate as i think surreydave suggested earlier...

thanks again,

Ned.


James - 30/10/03 at 12:15 PM

quote:
Originally posted by ned
Northy,

It looks like your webers are tilted upwards slightly, mine would be tilted down with the manifold as it is.



Just bolt it on upside down! Problem solved!

Cheers,

James