How many would be interested in a blank Nailhead heatriser valve adapter?

I am thinking of making some blank heatriser adapters that would fit on the passenger side exhaust manifolds of the '63-'66 401 and 425 Nailhead. I think on the previous years this was part of the manifold. The heatriser is currently not being made, and NOS is expensive and very hard to find.

Since they are made of cast iron, it is common for them to crack across the center, and if it breaks in half, it's useless. If you don't have one that is at least in one piece, there is no way to attach the exhaust pipe to the manifold.

I'm trying to judge if it would be worth my while to purchase enough materials to make an initial run of a dozen or so of these. They would be made of steel, and would be dimensionally correct to fit but would not have the butterfly valve. Since we only drive our cars in the warmer weather and some of us have the heat riser passages blocked off anyway, I thought this might be a good idea.

What would you think would be a fair price, considering NOS if you can find one can go for over $100?

Please vote in the poll if you would be interested, and thanks for your replies. :bglasses:

 

Great idea!

The heat riser valve on the '63 Nailhead is in the manifold, so I don't need one if I keep the stock manifold over there. But it's still a great idea.

 

Joe-I have the 66 engine in my Rivi, but I admit I don't know what this part does? Or, more specifically what the advantage is? This is a stock part that everyone would have, I take it.
Forgive me, I am a newbie fo sho

 

A heat riser valve is a butterfly valve that is normally closed when the engine is cold. It directs the hot exhaust around through the intake manifold to warm up the carb faster in the colder weather. This prevents icing around the throttle plates on cool humid days, but is really not needed in the warmer weather. Without this functional part, the motor will have a tendency to stumble and idle rough during warm up but prolly only when it's below around 60*.

Repro'ing a heat riser valve would be beyond my capabilities, but I have the machinery to easily make a non-functional one without the butterfly in it out of heavy steel as opposed to the original style cast iron. This would also be less restrictive from a performance standpoint. I could also make one to fit the 430 if there is a demand for them. :Smarty:

 

Joe, I know for sure mine is frozen in one position. I dont have a use for the heat riser as mine is a warm weather cruiser only.

I am on the fence as to if i would replace it just because, but if any exhaust work was ever done on a head pipe then definately.

Its to cold to go out and look, my question is would a head pipe not mount to the exhaust manifold w/o a riser or the proposed riser substitute? I am not sure if the riser mounts to the exhaust manifold with a 2 stud and bell shaped inlet arrangement like the headpipe mounts to the riser or the non-riser side exhaust manifold. I realize the existing headpipe would be to short w/o the riser in place but not sure if it bolt up.

 

You are correct, there is no way to bolt it up without a heat riser in place. That's why I thought there might be a demand for this part. :bglasses:

 

I think it's a great idea. I myself, am not in need (yet that I know of) for one of these. But it could happen due to all the Buicks in the family. Nailheads and not. I have not yet checked all (215-455's) for them or thier functionality.

It could mean an inexpensive solution for us now, or in the long run to use this. Exhuast stuff is a PITA as it is. I'm imagining this, as basically an adapter or spacer that is required to mount a stock type exhaust system, with minimal headaches.

I will vote yes, and hope we can come up with similar solutions as well.

 

This item is a very good idea. I'm in need of one and was thinking of tryng to do the same but don't know where to start to have something fabricated. Count me in for one (maybe two).

You won't know you need it till you drop the exhaust and the heat riser valve is stuck up there and you carefully try to remove it. It comes down in pieces because of the years of rust that ate it up from inside the the choke shaft bore. THEN you need this. took me way to long to find a used one that luckily rusted in the open position and didn't break on installation.

Worthwhile piece to have in stock for our Rivs.

 

Good idea

I'm in... any adaptive part is an asset. I show part # 1377480 as the manifold for passenger side Electra, Wildcat and Riviera, 64-66,401-425. Presumably all came with the heat riser. Just wondering o No: if anyone with a 364 has a riser as this manifold is supposed to fit the 401-425?

 

I am down as a Yes.

 

I'm in, Can we get a $$ idea before you start? Another nice item would be a bolt-on x-over adapter to go to 2 1/2" pipes.

 

I haven't gottten to the point of fiquring out my costs yet, I'm just trying to get an idea of demand for this part. If I had to guess, maybe somewhere in the $50-$75 range unless I make it out of stainless, which would cost much more. :bglasses:

 

Joe,
How does it connect to the intake manifold? Before this thread I didn't even know my Nailhead had one. It does not seem to be connected anywhere.

 

The exhaust passageways cast into the cylinder heads branch out to passageways that connect to and go through the intake manifold.

When you restrict the passenger side exhaust flow, the exhaust must pass the other way through the heads and through the crossover passages in the intake manifold(warming up the base of the carb) and then on through to the head on the driver's side and out the driver's side exhaust pipe. That heats up the motor faster. It is also the reason why if this valve is stuck closed it will cause overheating.


I looked in the book for an illustration but I couldn't find one. :Smarty:

 

I think it would be a good idea. I haven't got to this stage in the build yet and the plan is to run the car as a sumemr car only. However it will have to start up from cold so presumably this part will connect to the choke and make the choke operation work correct on cold start up no?

If my thinking is correct then I'd have one please!

thanks
Nick

 

These are almost ready......I had one all made up but I wasn't happy with the way the universal flange looked. I'm going to have 100 flanges made special, maybe more.....I doubt if I'll sell many more than that. Depending on how quickly this happens, I should have some ready soon. :bglasses:

 

Put me on the list to purchase one. :beer

 

Please post picture of this heat riser for sale

Can you take and post a picture of an original and your new product together?

Thanks

kg

:3gears:

 

As soon as I get one made with the new flanges I am working on having made I'll do that. I'm still waiting for a cost estimate.........if it's too expensive I'll have to go with the universal flanges that look kinda mickey mouse.......if I'm not happy with how it looks I won't sell it. I want these to be top notch quality parts. :bglasses:

 

I would think it would, as long as the heat riser is the same and that fits......the 1/2" holes are 3-5/8" apart (on center) and the center hole is about 2", and it will end up being about 1-1/8" thick from the face of the flange to the end of the taper that attaches to the exhaust pipe. :bglasses: