St182 Stainless Steel Manifold?

[mjd_73]

Hi,

Where can I get a stainless steel manifold for my celica ST182 or is there no such thing?

Many Thanks

Matt

[mikeb]

I've never heard of one, but that doesn't mean they were never made.

Why would you want a SS manifold anyway? The OEM one is tubular and 4-2-1, so there's not much improvement to be had.

[mjd_73]

Hi Mikeb,

It's just that I've heard weird and wondering stories about that a Stainless Steel Manifold increases your BHP but I'm all new to this so I might being misled.

Thanks

Matt

[mikeb]

I can't see how the material a manifold is made of would make any difference to performance, unless there is some thermal advantage of SS.

On lesser cars, that have cast iron manifolds, a tubular one would be a performance upgrade, but the Celica comes with a tubular manifold as standard. The only reason to for stainless would be cosmetic IMO.

[daktari]

The material is neither here nor there. The only benefits are as you say mainly cosmetic, although a thin wall tubular manifold will dissipate heat quicker than a cast item. The only other reason it would be better than the stock tubular manifold would be if it was matched exactly to the exhaust ports and each of the individual branches were the exact same length thus helping the gas flow. Aftermarket SS GT4 manifold below shows this to good effect.

[james_corolla_cuthbertson]

Stainless steel can maintain a more highly finished surface than mild steels, and thus have a lower coefficient of friction - less resistance to gas flow.

Having equal length runners from the head to the collector is great for turbo cars as the distinct pulses help accelerate the turbine faster. However it's rubbish for a naturally aspirated engine. Instead, tuning the lengths of runner from each cylinder to the firing order of the engine as precisely as you can will help each pressure pulse and subsequent vacuum extract the subsequent pulse more efficiently - more power.

Stainless steel doesn't rust - there are lots of highly corrosive emissions from burnt petrol - Sulphur dioxide for one, which when mixed with the condensed water you get from a cold engine forms sulphuric acid! Same as acid rain!

If you can get a cheap stainless manifold or better still make one yourself then great, but it's only really worth bothering if you are going to really tune the whole engine. Bit of a waste otherwise.