Jump to content

Is there a need for big car exhaust manifolds ?


Recommended Posts

Hi Guys,

This might be just an idle question, but I'm wondering if there is a need / market for exhaust manifolds for the "big" straight 8's.

I'm talking about the 320's.

I have access to a very fine sand casting foundry AND a machine shop that can do close tolerance machining on a prototype or production basis.

We could cast a direct replica from the same class 30 iron OR from today's modern equivalent alloys.

My concern is the heat riser parts in the center section, such as the spring.

The shaft, butterfly, and counterweight can be made fairly easily, using OEM parts as a guide.

So my question is; Do you think there is sufficient need out there to start production of these ?

Your thoughts would be welcome..............

Mike in Colorado

:confused::confused::confused:

Link to post
Share on other sites

Talk to the suppliers like Bob's...... they can tell you how often they have a request.

The tooling cost and minimum orders are often the issues when looking at these projects. If you have the contacts and experteze then make one or two. Then get them on cars to see if there are any issues before jumping in with both feet.

Link to post
Share on other sites

The center section of the 320 exhaust manifold and the heat riser section that bolts underneath it are very, very hard to find in good condition, unless you want to pay $600 or $700 for the reproductions that Bob's Automobilia sells. There is a market if the price can be kept under $500. Seems like everyone who is restoring a straight eight Roadmaster from 1936-1951 needs this part.I recently had to replace both pieces on a '49 Roadmaster. It took me 9 months to find a good used replacement. I could have bought both from Bob's Automobilia, but the car wasn't worth spending that much $$.

Pete Phillips, BCA #7338

Link to post
Share on other sites

According to the latest "Bob's" catalog, they sell a replacement manifold for the 248 and 263 for $695.00, but none listed for the 320's.

That's why I'm asking if there is a need out there for the big motors.

How many years /models took the 320 motor, and how many are still on the road ? Or not on the road for lack of this part ?

My goal is to price the 3 pieces Very Close to Bob's price, but before plunging in I'm just trying to get a "feel" for the market.

Mike in Colorado

Link to post
Share on other sites

Look at you latest BCA Roster........ in the back it list all years of Buicks and the number made. The Specials had the small engine and everything else had the large engine. Using 1937 as an example there were 152,773 Specials (small engine) built not counting export models.

There wre 53,283 model 60,80, 90 and 91 that use the big engine. This tells you two thing, roughly 1/4 of the 1937 Buicks were big engine cars.

However, the small engine exhaust manifold was much less likely to crack and as noted above, the available used parts were 3 to 1 more common than the big cars. The Roster list roughly 175 big engine 1937 in the club. How many need exhaust manifolds?

Last.......pricing. If you sell them at the same price as another Buick parts vendor, you are less likely to get an order for a couple of reasons.

(1) You are an unknown, until your product gets out there and get good reviews then .......

(2) Existing vendors will get the orders because they have an established reputation and someone restoring a car can order his exhaust manifold and other parts at the same time.

If you plan on going forward with reproducing the manifolds, you must be able to make them for less than half the current selling price. This will allow you to mark them up and recoup your cost at a selling price about half way between your cost and the current selling price. Once you start selling manifolds at lets say $450, the existing vendors may match your price and you will need some cushion to go lower in an effort to establish your product. Another exposure is someone else out there thinking the same as you....... what happens if he hits the market with a reproduction at the same time as you? You must have the lowest production cost and the lowest selling price.

As Pete noted, he did not pay $600 but might have paid $450, it depends on your threshold of pain $$$$

Link to post
Share on other sites

The 320 straight eight is used from 1936 through 1952 in Roadmasters, Centurys, and Limiteds. The '52 is a four-barrel so that one is out. Virtually every owner of a 320 straight eight out there needs one or needs a spare, because they are almost always cracked or will crack in the future. Most of the ones in salvage yards are cracked due to water getting in and freezing. I am lucky enough to have found a spare one, but I would buy another, just because I am sure I will need one in the future.

Pete Phillips, BCA #7338

Link to post
Share on other sites

Barney has some good points, but I'd like to call him on his last paragraph. Who are the current vendors ? I've not seen or heard of a source for the big engine manifolds, either NOS or reproductions.

But with over seven thousand posts, and the guy that "forced" me to buy a manual and parts book, who am I to question him ?

I do believe Pete has a point, in that there is a need due to the life span and models of Buicks that the big motor was used in.

There are lots of parts particular to the big cars that need to be made. The "clutch equalizer" is one that we discussed at length. A relatively easy casting to make, and virtually nonexistant out in the marketplace. Fortunately, after searching for several months for a replacement, I weld repaired mine.

Hubcaps for a 80-90 series car are very seldom available, and NOS parts are not generally available. I could go on and on about big car parts, but that's another discussion.

Like Pete, I was able to find a good replacement exhaust manifold for my '40 Buick, and I have the old, though cracked, manifold to copy. My foundry can "digitize" it and create a truely faithful replica, right down to the part number and foundry marks. We have done this with model "A" ford heads, even simulating the barbed wire nubs on top, that ford used to suspend the cores for the water jacket.

So now my next step is to get some quotes from the foundry and machine shop, and see what the numbers say.

Mike in Colorado

Link to post
Share on other sites

Mike, Bob's does sell reproduction manifolds for the 320. I bought mine from him a few years ago. I think they were around $800. I remember talking with bob about the manifolds, and this is something that you might to keep in mind. He told me that if a customer buys only one piece and not the whole set, then Bob keeps the remaining pieces set aside. When the manifolds are cast, they are made to fit together. A piece from one set may not fit snugly with a piece from another set and cause leaks. So the sets are numbered. He said that sooner or later, that customer will call back and say they need one more or the rest of the pieces. He then looks up the number of that set, and finds the remaining pieces for the customer. So basically, he is storing the pieces for the customer if they don't buy the whole set.

Personally, I would be interested in seeing a set done in a modern, or better material. Something that wasn't so prone to cracking.

Phil

Link to post
Share on other sites

I would think there'd be a bit of demand for a 1952 4V version for the 320. Suggest it be cast with flange to fit both 4V carb bolt patterns (old/modern). Other than that, there's a limited demand for the 41/42 Compound Carb intake/exhaust systems for both the 320 and 248/263. Especially if you can sell both halves of the exhaust manifold plus the intake manifold for under $500.

Link to post
Share on other sites
We should start a thread as to what we can supply and put it up top of the forum as a "Sticky"!

Cheers

Grant

PS Hot enough for you Danny?

We cracked 46C+ today. That's a 115F+. Yep, it was a stinker. :cool:

I just closed up shop and sent the boys home at lunch time and spent the afternoon at the pool.

I should really pull some of the crap stacked on and around my '38 60 and see what condition my manifold is in. A few years back I saw a '38 60 engine that run a fire pump and its manifold was cracked.

Danny

Link to post
Share on other sites

Thanks for the info Phil. In looking at Bob's catalog, it would be aprox $760.00 for the rear and center section, and I don't see a listing for the front section, but logic would dictate that part for around $360.00, so in todays pricing it would yield a total of over a thousand dollars. I think we could do quite a bit better than that. I'll be visiting my foundry soon, and we will check my old bits with the spectrograph to see just what she's made of. I suspect class 30 iron, but it may be ductile Fe. In any case, once the pattern is made, you can pour any alloy you want. We could even make thse parts in stainless.

Jr9162, $500.00 for both the in and out would really be pushing it, but an aftermarket 2 carb intake as a faithfull replica is a real possibility, down the road. You get into the limited supply of carbs though, and to change the mounting base in the casting for another carb, would instantly be recognized. Although a separate adapter casting could be made.

Years ago we used to pull S.U. carbs off Jag's in the bone yard for 10-20 bucks, build a 90 degree intake from tubing and mount them on Harley's. Sure made those old pan head motors come alive........

Mike in Colorado

Link to post
Share on other sites
Mike, if that would be universal to use on my 90, might of course be interested too, or both outside sections anyway as I have a new center section.

Sandy

Sandy,

I doubt yours and mine are common. Just too many years between them. If the length and port spacing were the same you could update the whole thing, but then you would have to give up that wonderful Marvel carb, which I know you really love ?????

Did you see a recent post regarding a Marvel carb shop in Phoenix, Az. ? I stumbled across it last night, and they have a "test" engine they run them on, and you are not supposed to fiddle with them when you get it back. I'll look around again and PM you.

Mike

PS Didn't you get the memo from Mr. Earl (our moderator in chief) about updating your "signature" ?

You are supposed to list who you are, where you are, what's in your stable, first of kin, and a whole

bunch of other stuff. You can even add a really big picture, like Grant does. Blows my big honking

avatar out of the water.

Edited by FLYER15015 (see edit history)
Link to post
Share on other sites
The 320 straight eight is used from 1936 through 1952 in Roadmasters, Centurys, and Limiteds. The '52 is a four-barrel so that one is out. Virtually every owner of a 320 straight eight out there needs one or needs a spare, because they are almost always cracked or will crack in the future. Most of the ones in salvage yards are cracked due to water getting in and freezing. I am lucky enough to have found a spare one, but I would buy another, just because I am sure I will need one in the future.

Pete Phillips, BCA #7338

Thanks for the post!

I'm with Pete. Both of my exhaust manifolds were cracked and I had to have them welded. Not sure how well the welds will hold, and for how long. I'd be interested in a quality set as back ups.

Link to post
Share on other sites

PS Didn't you get the memo from Mr. Earl (our moderator in chief) about updating your "signature" ?

You are supposed to list who you are, where you are, what's in your stable, first of kin, and a whole

bunch of other stuff. You can even add a really big picture, like Grant does. Blows my big honking

avatar out of the water.

Wasn't intentional! I had no idea at the time it would appear so large! Plus, it's ancient. That cup of coffee is long gone. Come to think of it, the whole property is gone thanks to earthquakes!

Cheers

Grant

C

Link to post
Share on other sites

Well looky who's awake down under. I know your lurking, 'cause your green light is on.

Danny posted the rather warm temp's your having a while ago.

I heard from OCM that it was 62F in Ft Collins today.

We got up to 48F here in the mountains.

What do you mean the "whole property's gone, You O.K. ?

Mike in Colorado

Link to post
Share on other sites
Well looky who's awake down under. I know your lurking, 'cause your green light is on.

Danny posted the rather warm temp's your having a while ago.

I heard from OCM that it was 62F in Ft Collins today.

We got up to 48F here in the mountains.

What do you mean the "whole property's gone, You O.K. ?

Mike in Colorado

All good Mike. Gone, as in too badly damaged by all the earthquakes we've had (11000 since Sept 2010), so the govt wrote the whole subdivision off, and now the houses are slowly being demolished. But it's all good, because my folks were looked after by their insurance co, and now the coupe resides in a new 4 car garage attached to their brand new house! My house is probably due for demolition as well, due to my concrete floor being out of level by about 7". It's a slow process! Quakes are still going on. I thought they were dying down, and they have been to a certain extent, but last night, we had a 4.6, just to keep us on our toes!

Cheers

Grant

PS Sorry for the thread hijack!

Link to post
Share on other sites

Grant,

Good to know your O.K. !

Should we tell Danny about the "green light" ? NOT,,,,,,,,,,

Sandy,

You will have to find somebody who knows more than me regarding the '33's motor, like how many years / models it was used on.

Is it a 3 piece deal like mine ?

My 320 cid engine was used for many years and models, so the cost of the patterns can be justified.

Mike in Colorado

Link to post
Share on other sites

OCM: 28-41 Parts Book shows 1933 80 series and 1933-35 90 Series exhaust manifolds (all 3 sections) use the same part numbers. I doubt the later ones for the 320 will fit as these are very different engines. Good luck on your search. We'd all like to find someone or shop that knows how to truly repair 75-80 year old cast iron parts.

Link to post
Share on other sites

The front section for the 320 engine exhaust manifold is NOT being reproduced at this time. The center section for the 1952 320 engine is also NOT being reproduced at this time. This particular center section Incorporated the heat riser assembly and was also sold as a replacement for the earlier center section and riser. I do NOT know if the center section for the 4 BBL intake is the same as for the 2 BBL intake. Buick will show different part numbers because the choke stove tube is in a different location. There may be other differences.

Having the parts cast is only 1/2 of the fun. There is also some machining that has to be done carefully for the arms to slide into the center section without being too loose.

If you could find a way to make these parts right and cheaply they will sell. Just remember however these engine have not been made in over 50 years so there is a limited market.

Bill

Link to post
Share on other sites

If my exhaust manifold, broke, blewup or whatever and I didn't have the parts, you have them made, regardless of costs, or the option to sell a broken vehicle.

When Mike was here on one of his visits, he said my spare would be easy to reproduce, just the cost of the first one. My problem is the 1933 Engine. Not a lot of us around. I'm very attached to my 1933 Buick 90, so I'd have a bit of shuffling around to do, but that part of this hobby.

I bet I could get 5 of us to split the costs for a set of exhaust manifolds for a 345 monster, maybe. ?

Probably a year project at best, as the only 1933 Buick mechanic is the old guy in the mirror. Yes all the fitting etc., etc. Bob Engle, Mike, Grant and guys like that could walk me through on this forum.

I hope this is a moot point for me tho-

OCM

Link to post
Share on other sites

My observation is that 320's are very rare in NZ. There are the lovely 90 limo & convertible in Napier, the '39 Century in Southland and survivors of a batch of 1947(?) Roadmasters that were used for tourist limo services by Railways Road Services until the mid '50s (replaced by 1955 Cadillac Fleetwoods).

After a series of patchwork welds of the exhaust manifold (and eventual replaning of the inlet manifold to an unusable state) we bought a repro exhaust manifold from Queensland (via Bob's!). But this is for a model 41/248".

Link to post
Share on other sites
  • 2 weeks later...

O. K. Guys,

I'm off to the foundry next week, to start getting quotes on 3 exhaust manifold castings for a '40 320cid engine as follows;

P/N 1288764 Front section I have a good sample casting.

P/N 1288765 Rear section I do not have a sample, but it is a mirror of the front so we can flip the model to make a pattern.

P/N 1394846 Center section I do not have a sample, so I need to buy/borrow one (in any condition to create stl files from).

Anybody have a center section that they want to dispose of OR lend out. If it's cracked / broken, I don't care. We're just going to reverse engineer it to make a pattern for this casting. We may thicken the rings that receive the front and rear sections just a bit.

And of course we will use "modern alloys" for the castings.

I could post on the Buy /Sell forum, but I thought the thread followers here might be of some assistance.

Mike in Colorado

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...