Hi all

I am currently thinking about fitting 40 DCOE sidedraft webers. I have'nt looked very hard for the stuff yet and have'nt bought anything yet.My questions:

I know that there are water holes underneath the intake ports on the head that needs to be plugged as the weber manifold does'nt have these holes to circulate water through.
What is the easiest, reversable way of plugging these holes?
Will the clamping force of the intake manifold and the intake manifold gasket not be sufficient enough not to cause radiator water to leak through?
What must be done with the distributor's vacuum advance?
And must I make a catch tank for the tappet cover and engine block's breaters?

Thanks.

To answer your questions.

The inlet manifold should cover these holes & seal them, so no pluging should be required. The original manifolds did not leak water at this point & the new one shouldn't either if it is properly made.

The sidedraught Weber carbs do not have provision for ported vacuum, so you will need to run without the vacuum advance.

I have not yet seen a twin Weber manifold with provision for the PCV function, so you will need to either create a suitable suction point for a PCV valve, or go with a catch can.

Nissan Motorsports sold a "stud and plug kit" , the plug part of the kit was to threaded plugs. You tapped the 4 water holes and then threaded the plug in.
As for vacum ports you could drill them if you wish but I'm not sure anyone bothers.

Tom

I have a little filter on top of my rocker cover, on the A10 the block breather vents into the air, but it was once suggested to me to plumb it into my extractors for maximum efficiancy, I have never tried it but it sounded like a good idea.

I dont run any vacuum advance, and with all that air flowing through your twin forties you wont have any vacuum to speak of anyway.

Thanks for all the replies.
Basically the manifold will be bought from a place that sells brand new weber carbs and also manifolds.I did phone them in the past and they did have a factory made manifold suited for the GX cylinder head for sidedrafts.Did'nt ask them about the water holes because I think they will not know.

I am thinking of a nice polished stainless steel oil catch can that has a small airfilter ontop and then pluming the tappet and block breathers into it.

Will run without vacuum advance and just advance the timing,test drive and advance again until it pings and then retard it a little to be save and use our highest octane fuel.

I just installed an oil catch can to combat any more "bright ideas" I may have about fixing my car. My friend was telling me though that they're supposed to be plumbed back into the engine (topof sump is a good spot since it's easily modded), the point is for the system to relieve pressure and let the oil flow back down. It's ussually not going to be a problem if you keep the oil levels right but it does happen.

To explain the "bright idea", the other day I added about 2 litres or more of oil to my motor cos I couldn't see anything on the dipstick and it was a hot day. I had only changed the oil the other day in preperation for some fun at the track. Anyway, after the oil thing it ran worse and started smoking like a dutch oven. The oil was being blown out of my rocker vent all over the engine.

I bought a catch can later on in the day and strangely enough It's still bone dry. The oil has leveled itself off by going past my rear main seal or sump gasket

@littledarkone

Did your oil catch can have a little airfilter ontop so that it can relieve preasure?
Sounds very strange because I have seen quite alot of cars on this site, even rally cars that see lots of high revs the whole time with oil catch cans.If it does'nt work then I think they would'nt have gone to all that trouble of fitting it.

It's a cheapo version that's meant for more modern cars so I'll need a longer pipe to put the breather element on.

I'm not saying they don't work I'm just saying you have to be playing hard to need them.

el' cheapo That's the can I bought, it's a "Monza" one so the first thing I did was take the gay arse sticker off it. I don't care about it so I spose I could re thread the output hole (it's not even metric or sae just some wierd cheap thread) )and find a lonnger fitting for my breather