The 230 Headerfold project

[monkeymissile]

fascinating stuff, that guy really knows what he's talking about. I guess I keep thinking that the 230 is just too small and an M-Series RPM range so low that a lot of this info doesn't necessarily apply in the same way. I think the trick is to extrapolate the most critical principles and make it work for this application.
For instance, does anyone specialize in low RPM headers? Off to Google!

[monkeymissile]

good links

http://www.carcraft.com/techarticles...ics/index.html

- has easy to understand equations. According to them I want 1.375" primaries for a peak RPM of 3000. Ha, that's what I initially guessed!

http://www.superchevy.com/technical/...der/index.html

[John Waak]

You are quickly becoming the expert on this project, and rightly so as it is your project. I certainly agree that maximizing the 230's performance is a strongly desired goal. However, the words "robust and worry free" describes the basic character of these trucks. They are qualities I would not want to lose in an upgrade.
Press on, Justin, you're doing good.

[monkeymissile]

You are quickly becoming the expert on this project, and rightly so as it is your project. I certainly agree that maximizing the 230's performance is a strongly desired goal. However, the words "robust and worry free" describes the basic character of these trucks. They are qualities I would not want to lose in an upgrade.
Press on, Justin, you're doing good.

John,
thank you for the kind words and encouragement. They'll come in handy later when I go through my "do you really need to be doing this?" stage.....

[maineSS]

You've accumulated a lot of info, the key is finding which is usable. Looks like one of the more important questions is "How hot will it get?" I originally mentioned coatings as a guard against fire hazards, but the Jet-Hot oxidation tests show why cheap headers never last very long. If temps consistently run over 1200 deg, Stainless isn't really cost-effective either. It looks like header surface temps are within 100 deg of the exhaust gas, so fitting an exhaust manifold thermocouple to your leanest-running cylinder may show whether coated steel or Stainless is the best material. I ran a 70% VE airflow number for the 230 through one of Vizard's header formulas, and came up with a figure very close to your 1.375" primary dia, so it looks like you're pretty close there.

[monkeymissile]

temps

Any idea how hot those pipes can get under normal to moderate use? Seems like 1200 is a bit on the high end.
It would be cool to develop a water jacket for the header to keep it cooler. I've seen them for antique motorboat headers, very cool (har har).
I assume my leanest cylinder would be the one(s) farthest from the carb? I might have access to a decent thermocouple

[maineSS]

Cyl #1 or 6 would be the candidates for a thermocouple- you want to get into the gas stream, not surface temp. Here's an Austrailian Jeep site that is going our way http://go.jeep-xj.info/HowtoExhuast.htm .

[monkeymissile]

exhaust down under

Cyl #1 or 6 would be the candidates for a thermocouple- you want to get into the gas stream, not surface temp. Here's an Austrailian Jeep site that is going our way http://go.jeep-xj.info/HowtoExhuast.htm .

glad to see that other people are paying attention to the details too. To be honest, I never realized how complex an exhasut system actually is. I have found all of this new knowledge fascinating and it's definitely helped me guide my design. I hope to have some computer images of the latest design by the end of this weekend.

[John Waak]

This may be stupid question time, but . . .
Does the absence of a manifold heat control valve pose significant cold weather problems? Or, is heating the cold weather gas vapors handled in another way?

[monkeymissile]

This may be stupid question time, but . . .
Does the absence of a manifold heat control valve pose significant cold weather problems? Or, is heating the cold weather gas vapors handled in another way?

John,
I was told that the heat control valve was less critical unless you were in a consistently cold climate. I don't think I could design an effective exhaust system with a similar valve so I'll resort to crossing my fingers.....unless you've got some ideas?

Justin

[John Waak]

I live in south Texas. Mother Nature is my heat control valve.
Nevertheless, I had wondered what the northern climes would do about the missing valve; block heater, perhaps?

[MoparNorm]

Since the manifold heat control valve (most of whom are rusted shut) relies upon a warm motor to heat the air around a carb, the motor has to be running first anyway. I'd say it is of no consequence, and if it is, then run a heat riser like the factory used on later model trucks.
The heat riser doesn't know if it's attached to an exhaust pipe or a set of headers.....

[JimmieD]

The enemy there is 'cold', so go for a head shot: add a water jacket block heater. There are also simple propane fired systems running independent of normal coolant system.

Note: 'Warm up problems' only critically effect 2 systems: oil supply & fuel supply. Adequate spark at statup is another related issue. The cold engine and especially its cold lubricant make cold temp starting more difficult, and fuel atomization and delivery suffer markedly. A pre-oiler solves #1 and can add 75%-150% to the life of the engine. With rotating & reciprocating assembly pre-oiled prior to startup a large part of the cold warmup battle is already won; because it then requires far less of the gasoline's power to move the cold engine parts. As the engine warms tolerances widen, allowing less friction, so the pre-oiler steps into that problem ahead of time as well by forcing oil into those tight cold clearances.

The fuel supply and atomization can be solved by addition of fuel injection, not an impossible task. In lieu of that a cold start injection of propane might be considered, if there is a pre-oiler in place. This is a relatively simple matter [intake fogger] not a whole lot more complicated than a gas barbeque. Attention to details will ensure that it doesn't become the latter.

Heat risers were the industry's low buck bandaid to step around a problem rather than to address it head on. If you want a truly successful result in this project it might be good to look at all related systems and see if they may also be economically brought into an integrated systems approach.

It's somewhat like war. The soldier is concerned with the enemy's bullets flying in his direction and fires back at what he can see, right here, right now. The general steps back and analyzes the war, not a fire fight, and determines to win on all fronts. December 7th reminded us of what it takes sometimes....

[monkeymissile]

I live in south Texas. Mother Nature is my heat control valve.
Nevertheless, I had wondered what the northern climes would do about the missing valve; block heater, perhaps?

John,
yes, I'll probably use the block heater since the engine's so easily fitted for one. You probably have to keep a closer eye on your radiator more than I do though!

Justin

[monkeymissile]

Could you gents direct me to the examples of "pre-oiling" and "heat riser" systems you're referring to? I am now intrigued. Have you seem these successfully added to our trucks?
Thanks!

Justin