Stainless Manifolds

[sporting wood]

Thinking of going stainless with a 4 branch for my Mk2. What's better a 4-1 or 4-2-1?

Also is it necessary to replace the engine mounts to solid mounts before getting one so it won't crack?

[Simply Ed]

If I'm right in saying (I'm sure somebody will correct me if I'm wrong) a 4-1 manifold will not give as good a torque reading low down the scale, but due to the simplicity of the system will give a higher torque gain nearer the top of the rev range. A 4-2-1, generally regarded as the best option, gives better torque through low and mid range, with a power gain at the top of the rev range. Not knowing you or your car I couldn't say what would be best for you, but generally, most people go for 4-2-1, therefore there must be reasoning behind that! Hope that helps!

[dabill]

i've been looking into this, and had several peoples opinion.

all prety much ring the same, dont get an ebay manifold, get a miltek or simular, and get a solid front mount.

reason for the ebay manifold is they are just pants, the whole idea for the manifold is it allows exhaust fumes to exit in the most efficient route, reducing gas swirl which slows the exit.

the solid front mount also helps reduce tension on the bolts and exhaust mounts.

also, had a top tip, if you have a stainless manifold and system, then wrap you rubber mounts in duck tape. makes them 100 times stronger... and you rubber mount bill alot smaller...

[Organisys]

Just fitted a Raceland Manifold on my 8v daily. Fit was ok (just) It sounds great, and saved me about £200 over a Miltek manifold. Bit less torque real low down, but better throttle response over 3k. did solid front engine mount at the same time too.
 

[...joe]

you actually need a solid front mount as stainless is alot more brittle compared to mild steel, so the rocking of the engine can crack a stainless manifold.

the raceland manifolds seem to get mixed reviews. we fitted one to a vr6 corrado and it fitted perfectly and so far has had no problems!

[sporting wood]

Sounds like a 4-2-1 is best for me but I'll definitely need a solid front mount first. That's another thing on the shopping list

[Nibbzy]

yeah i have a raceland one on mine n it fits great no problems at all and its defo a massive difference in top end torque... roars like a beast too.. lol should wrap it really but i just havent got round too it. as has already been said u need the solid front mount for the engine rocking, it will snap clean through the stainless systems pretty easily after a bit of hammer!

[dabill]

with the solid front mount, surely all the tension and strains etc that are reduced or eliminated by the normal front mount are then transferred somewhere else in the subframe? so does this cause any damage elsewhere? or does it just result in a bumpier idle?

[Organisys]

with the solid front mount, surely all the tension and strains etc that are reduced or eliminated by the normal front mount are then transferred somewhere else in the subframe? so does this cause any damage elsewhere? or does it just result in a bumpier idle?

The cross member that the mount is on is mounted to the chassis with rubber bushes anyway.
I'm getting a bit of vibration through the cabin (mostly the sun roof panel) but I aim to fix this by tweeking the idle speed up just slightly, and by fitting a sliver of firm rubber under the mount.

[...joe]

why the front mounts are a weak spot is because they are constantly being pulled whereas the rear and gearbox mounts are being compressed. any extra vibration is taken up by the other mounts and like rob says, the cross member is rubber mounted.
you will get some more vibrations but a rubber washer will help.