Cast Iron Hedder for the "A"?

Chris Haynes

Chris Haynes

Well-known member
Is anybody still making the Cast Iron hedder for the "A"? Not a stock manifold but a free flowing hedder.
Thanks in advance.
 
Max III at H & H carries the cast Iron Header ( 1-818-248-2347 ) and Sammy at Arizona Model A carries the header.
Thanks Max Sr.
 
The stock manifold sure seems pretty free flowing. What is the improvement to going to a more free flowing manifold on the A ?
 
Bill O'Brien said:
The stock manifold sure seems pretty free flowing. What is the improvement to going to a more free flowing manifold on the A ?
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Ummm, well it is a simple law of what goes in must come out. An engine is nothing more than a large air pump. If the spent gasses (exhaust) can flow out easier, then there is a slight scavenging effect that allows a new fuel charge to more easily enter the cylinder. This equals more efficiency which reverts to more power and better fuel economy. While it is much more complex in the real, ...that's it in a nutshell.

.
 
BRENT in 10-uh-C said:
Ummm, well it is a simple law of what goes in must come out. An engine is nothing more than a large air pump. If the spent gasses (exhaust) can flow out easier, then there is a slight scavenging effect that allows a new fuel charge to more easily enter the cylinder. This equals more efficiency which reverts to more power and better fuel economy. While it is much more complex in the real, ...that's it in a nutshell.

.
Click to expand...

Brent, do you know of any published dyno tests of the cast iron header?
 
BRENT in 10-uh-C said:
Ummm, well it is a simple law of what goes in must come out. An engine is nothing more than a large air pump. If the spent gasses (exhaust) can flow out easier, then there is a slight scavenging effect that allows a new fuel charge to more easily enter the cylinder. This equals more efficiency which reverts to more power and better fuel economy. While it is much more complex in the real, ...that's it in a nutshell.

.
Click to expand...

I must admit that was very well said!!! But I already have an excellent understanding of how engines work and how to make then more efficient!

My question was, how much more free flowing is the cast header for the A? The stock exhaust manifold does not seem to have much restriction to it....

Any dyno numbers out there for comparison ?
 
Unless you build a racing engine, you're going to get negligible real world gains from a header, regardless of whether its cast or tube. It's a simple fact that the stock manifold works well at the sort of revs the average street engine is turning. If you were doing a lot of running at 3000rpm+ then yeah, a header will be beneficial.
The hop up books of the 50s and 60s used to put headers at a 10% hp gain, but what they didn't tell you was that figure was only achieved in conjunction with cam, compression, porting and multiple carbs. Even then it's fairly optimistic.
JMO.

Oh yeah, I forgot the best bit.... headers LOOK very cool, and the tubing type will alter the exhaust note some. :D That's probably good enough reason for most folks.
 
the stock manifold is a log, with the exhaust exit past #4 cylinder. The exhaust gasses have to trip over each cylinder to exit the manifold.

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On a cast iron header, the exiting exhaust gases are isolated down their own path into a large collector. This may provide benefit to smoothing out the exiting exhaust gasses allowing for more efficiency.

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While your improving the exhaust system to be more free flowing why not rip out the choking suffocated flat head and throw in an engine with variable valve timing and 4 or 5 overhead valves per cylinder?

Sorry but it seems weird to me to try and improve how a flat head breaths. They don't breath well by nature, no?


Being that sounds a bit harsh, let it be known I appreciated modified "A"s just as much as stock ones. Nothing sounds nicer to me then a modified flathead!
 
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MrTube said:
While your improving the exhaust system to be more free flowing why not rip out the choking suffocated flat head and throw in an engine with variable valve timing and 4 or 5 overhead valves per cylinder?

Sorry but it seems weird to me to try and improve how a flat head breaths. They don't breath well by nature, no?


Being that sounds a bit harsh, let it be known I appreciated modified "A"s just as much as stock ones. Nothing sounds nicer to me then a modified flathead!
Click to expand...


I am improving the breathing by using the 3 valve set up by Riley. Now go outside and take a breath. :D
 
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