Making Hudson 8 Hi-performance exhaust manifolds

ivanz62

I have received a call from Pat McDonald saying that we can get more of these manifolds cast from his patterns. The cost of the iron casting without machining is $430 and the shipping is about $200 for the heavy iron manifold. Machining could be done by your local man using the stock manifold as a guide. We need to make about five to make this work. Let me know who is interested by replying here and pass the word to others who might be interested, please.
I will post this on the club website as well.
Ivan

terraplane8

I will take one - and await confirmation with interest.

One query, will this fit the earlier engines, ie '33 Terraplane 8?

50C8DAN

What exactly is this manifold. The picture is cropped a bit too much and I am not sure where the pipes hook up and go to?

paulrhd29nz

I'm In for one.
I can see the $200 cost for shipping one from over seas, but i would think that shipping 5 on a pallet would be less than $1000.???

Nevada Hudson

I might have some used ones in stock.

ivanz62

With regard to the shipping, I cannot personally estimate the cost for a pallet of 5. Have to ask a shipper. I recently received one shipped in a wooden box made to fit and shipping and duty cost almost $300 via UPS International from England to San Francisco.

The manifold has a single outlet in the front that takes a 2 1/2" pipe. It will fit a 1933 T8 unless it is right hand drive. I have attached another picture.

StillOutThere

So it will fit a right hand drive Railton chassis (shown) but will not fit a RHD '33 ET8. Right?

The big advantages of this exhaust manifold are that it is new, not warped or previously crack repaired and that it has the larger internal volume to speed exit of the combusted gases, is that correct?

ivanz62

Your assessment of the advantages is correct and additionally there is no intake manifold heat which is a benefit for high performance and a pain in the ass for warm-ups in cold climate!

These manifolds will fit a 33 ET8 but not a 33 (and maybe 34) RHD Railton with the narrower Railton radiator shell. There was a version made for those early RHD cars, but they are no more. The Railton Club has for sale reproduction accurate original manifolds--maybe 3 left at maybe $520.

terraplane8

It would in theory be possible to provide inlet manifold heat by creating a double floor under the plenum of the inlet manifold with hot water lines in and out. An inline tap could shut the water off when maximum inlet charge density is required.

bob ward

ivanz62, that's an interesting photo of the Railton's front chassis, the engine has been moved back by maybe 6"?

What happens with the chassis cross bracing, has that been moved back by a corresponding amount or did they do something different with that area of a Railton chassis?

Sent you a PM.

ivanz62

Please remember that nothing is made at this point! Looking for how much interest exists and then money to cast these to satisfy those who are interested.
Ivan

super651

Ivanz62 Will the manifold fit the 48-52 8 Cyl also ? Thanks so much

ivanz62

Yes, the manifold fits the stepdown 8. Two versions have been made--the difference is where the outlet is at the front. For 33-34 Raitons, the radiator and hood are more narrow than Terraplane or Hudson 8s. I have never actually seen one of these and there are none to buy anyway.

terraplane8

The exhaust ports on the pre-'37 are quite a bit smaller and round whereas the later ones are oval aren't they?

ivanz62

Yes the ports are bigger on the later engine. Because the ports of these manifolds were cast like the big port 8s, they can bolt on without restriction, and one can "port" the block to match the big port gasket and have the more free flowing exhaust as Hudson did with the later engines.

super651

Thanks so much Ivan for the reply. The owner of a 1949 is much interested in one for his 1952 8 engine.
Thanks so much.

terraplane8

Certainly the manifold on the T8 looks very narrow and restrictive especially at the outlet - it seems quite flat in the vertical plane compared to the post-'36 manifolds. It would be interesting to see what difference in power was to be found with the new manifold which of course will also run into a significantly bigger exhaust pipe compared to original.

Hopefully there are enough people wanting one for the project to proceed. I would have thought the Railton Club would be a starter for a couple of manifolds also?

terraplane8

Ivan, can you please clarify what needs to happen with the inlet manifold when using the new exhaust manifold? As the stock one is integral with the inlet manifold and obviously needs to be changed at the same time. I hadn't thought about that until I actually went and looked under the bonnet today at the stock set-up.

bob ward

You need an adapter between the inlet manifold and carby. You can see how Ivan has done it in the photo in the first post.

ivanz62

Quite right Bob. A spacer that is ported to match the carb you are using and to the Hudson intake manifold. This allows the throttle linkage to be at stock height and gives the Hudson engineered intake passage lengths appropriate for the engine's breathing.

terraplane8

This is the exhaust manifold on my Terraplane Eight. So once the exhaust manifold is unbolted from the inlet manifold, then I get a spacer made up to sit the carb on, is that right?

bob ward

Yes, and it doesn't need to be any more complicated than a piece of tube with a bottom flange to suit the inlet manifold and a top flange to suit the carby.