The Stovebolt Site Forums The Shop Area Engine Shop manifold carborator selection

A new exhaust manifold is needed. So now is the time to ponder new intake,exhaust and carborator combinations. I'm intrested in fuel economy for an around town 54 1/2 Chevy 235. It is my understanding some modifications in this area will help. What works? And how important is the heat box arrangment? Duel exhaust means what else do Ihave to think about? Is there such a thing as duel exhaust with heat box? How does water heat work,and is anyheat source really needed above and beyond the manual choke? Initially duel singles intuetivly make sence. Is this better Than stock manifolds with single duel? Just g3et me started here,and thanks.

BWK --

Welcome to the site. Ur question is broad and covers a lot of issues which I am also reasearching. Let me say that that I am a proponent of exhaust heat due to my experience with several of these trucks. In my view, the heat box as u term it, or the stock heat riser, is essential for single barrel carb operation in any geographical area where temperatures fall below freezing or even gets into the low thirties. Split exhaust with the stock heat riser is available from Kansas Kustoms.

Importantly, I have no experience with water heat which as far as I can tell is widely used. Others will advise you on their experience no doubt and many knowledgeable sources believe that it is superior to exhaust heat of the intake. I don't. My own experience is that the stock heat riser provides exhaust heat only until the engine reaches operating temperature at which point the head provides heat to the intake thru conduction at the attachment points and the heat riser directs all exhaust to the tailpipe. Water heat in my view cannot provide assistance when the engine is cold and only provides heat when the head has reached operating temperature. Accordingly, I have never spent much time looking at water heat--however others swear by it as I say.

There is no doubt that improved carburation benefits inline engines particurly at higher rpms. Dual carbs are widely used although a common complaint is the tuning time involved. Two barrels are also used and adapters are available for either exhaust or water heated intakes. Four barreled carbs are also used but I can only find water heated intakes for these. I expect that you will get a variety of views--all of which are valuable--gud luk and welcome.

I had my stock manifold modified by Kansas customs. Since mine had a crack he provided a core for $15 which was still cheaper than Fenton's and retains the stock heatriser and look.

[img]http://www.angelswest.com/_borders/kansaskustoms.jpg[/img]

Thankyou . A beginning.
Just how patient will I have to be to install itake and exhaust? Till now I was thinking it would be ,get a torque wrench and slam them onout of the box,but now there's this grinding and fitting thing. How does one grind a flat surface that doesnot fit the fist time? My wife insists on having duel exhaust for her own reasons so I'm going ther even with all my reservations about personally uncharted water.Again thankyou.

If you aren't comfortable about having to hack and grind, go with the Kansas Kustom split exhaust. Also, go to Langdon's Stovebolt and get a 2 barrel Holley-Weber carb and adapter for your stock intake. It will require a linkage change, but Tom can help you with that, too. This is a progressive 2 barrel, so you will get decent fuel economy and keep your low end torque.

Have you fellows not heard of the 1954 Corvette? It is probably now nearlly impossible to find one though, the exaust maniflod is FACTORY SPLIT and has a heat riser built in as part of the manifold.I do have one I'm using on a 59 261 and it works great, used the stock 59 mufflers and the sound was great, without being overly loud, to get into trouble with the local po-lice. and it fits up just like the single exhaust manifold, intake and all. I suppose that if you can find one that the price will be HIGH :mad:

The grinding & fitting is mostly required when installing headers and/or aftermarket intake manifolds. It can be time-consuming and require lots of trial & error. Kansas Kustoms does great work and can repair a bad heat riser in most cases. An unheated intake invites driveablity problems. The water heat vs exhaust heat issue applies to aluminum aftermarket intakes only - at least on 235s (Early Datsun 240Z's had water passsages cast into the intake manifolds). Water heat provides a more gentle, consistent heat source but will require some planning and thought to how the hoses will be fitted and routed through the cooling system.