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Those of you that are familiar with aftermarket performance headers, well what do you think of them? I have heard alot of talk on both sides on the V8 motors.
The most interesting thing I know about headers I got from reading a flathead book called Flathead Facts. The author started with a stone stock 8BA and proceeded with dyno testing all the common bolt on options for a flathead. Turns out exhaust modifications made absolutely no difference on a stock motor. In fact the test engine turned out to have a stuck closed exhaust thermostat in the cross over pipe during initial testing. Power with dual exhausts and tuning did not improve above the initial configuration.
On most otherwise stock flathead vehicles routing the driver's side pipe is a pain. If you need the sound of dual exhausts, then go with dual pipes off the stock manifolds. Otherwise the stock single pipe works great.
Thank you, that is what I had heard also. Do you know if electric fans work with these motors, and if you use the electric fan can you do away with that radiator shroud?
I'm not looking to "hop up" my truck, but that is very surprising info on the exhaust modification performance. The flathead has to be one of the few (or only?) internal combustion engines not to benefit, even a little bit, from an exhaust upgrade.
So the most beneficial mods. would be to the carburetor and intake manifold?
My friend who experimented with a high volume electric fan in front of his 8BA found he still needed an engine driven fan for city driving. Without the engine driven fan he was running the electric fan any time he was driving slower than highway speeds. Why do you want to get rid of the fan and shroud?
The most beneficial modification is to up the compression. Take whichever heads you want to use, factory cast iron or after-market aluminum, and mill them so you have approximately 0.050 inches clearance over the pistons and valves. The second most beneficial modification is carburetor and manifold. If you have a 49-53 motor you must install a different distributor with a proper advance curve when you change the manifold and carburetor.
At the present time I do not have a shroud for it, and I just thought an electric unit would be more efficient at cooling the engine..What distributors are they using when installing different manifold and carbs?
I almost always use an electric fan on my builds, although I haven't done a 6 volt one. When done properly, they don't actually run much unless it's pretty hot and slow or stop and go traffic. The main reasons to use one is that it (theoretically) frees up some horsepower. is much quieter and the part I like best is that the meat grinder is gone from under the hood.
I like a good pusher fan, hid behind the grill. But you have to buy a good one that moves a lot of air and you need an electrical system that can handle the extra load. The one on my 29 will pull over 50 amps for a second when it first comes on and about 15 amps steady.
If you are not working your truck hard you can get by just fine with the stock fan and no shroud.
The most common distributor for multi-carb, or four barrel, on an 8BA is a converted and re-curved small block chevrolet distributor. You can also get new performance distributors like MSD or Mallory but I hear they still need to be recurved to run right on a flathead. The currently agreed on flathead distributor Guru is the fellow who runs Bubba's Hot Rod Shop. He recently added another website, here are both: http://www.bubbasignition.com/49-53.html and Our Services
38 coupe, I thank you so much for your input I really appreciate it. However, I don't even let GM cars park in my drive way let a lone use a chevy distributor in my. I am going to investigate that ignition system when my motor gets back from the machine shop and it is sitting in the truck. I do not understand what makes the delco distributor any better than something from the Y block distributors in Fords. I think I still have one some where with dual points we put in a circle track car.