Let's build a drag race 8BA engine

Let's get this back on track... We're talking Flatheads here and looking for info/advice that pertains to them.

The engine has to be naturally aspirated. I will be using the Stromberg 250's.
I will be using SCAT H-beam rods.
Ross forged pistons with metric ring pack and undetermined CH pin location.
Edelbrock 1115 heads, this has been cleared with SEGA rules.
Cubic inches have yet to be determined.
Lots of porting in the block is to be expected.

I understand that a smaller engine can produce more HP per CI, but I need HP and torque to get to the end quickly. Bigger engine should do that better, right?

Nevermind the class limits of H/Gas, let's just think vintage drag racing to keep this going.
 
I understand that a smaller engine can produce more HP per CI, but I need HP and torque to get to the end quickly. Bigger engine should do that better, right?
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All other things equal, the answer is no.

It is HP per lb, that allows greater acceleration. If you were talking about just, top speed, like Bonneville or even, the standing mile, you might have a point.

The winner at the drag strip, is who gets there first and not the trap speed. Many races are lost, even though the the loosing cars trap speed is greater. The trap speed, is a indicator of actual HP.

In drag racing, the areas you need to work on are traction and using ALL the HP you have, just before getting to the line. That means gearing and gearing also, helps traction, it allows you to run a wider or, taller tire. So, you gear it to turn, slightly over your max rpm, at the line, in what ever the highest gear is, in the trans. Weight distribution, also will help, meaning not just the battery in the trunk but, everything mount as far back as you can get it.

If you just want to have fun, it doesn't make any difference. Just build your engine, to what you want and add the weight that it takes to stay in the class.
 
On the carbureation end of it, hook up a vacuum gauge and test the vacuum at WOT, in your torque range (Hardest pulling) and if you have more than 1.5" of vacuum (you need bigger carbs) or less than .5" (you need smaller carbs) and you need to keep the A/F ratio, as close to 12.5, as you can.
 
You don't need a huge engine. There was a guy on here ("MTFlat"?) that ran a steel '32 3-window with an injected flathead that ran consistently in the 13's and occasionally dipped into the 12's. As I remember, his engine was in the 260-270 ci range.
 
For drag racing you do not need to worry about what class you fit in! Just go bracket racing. No rules to meet except safety requirements. No worries about running against any cowardly cheaters. No teardowns. Just do a few time trials, put your dial-in on the window and go racing! Your 15 second flathead can win over a 11 second Corvette if you can drive good enough. Quick reaction times and consistency win races, not ultimate HP.
 
40 Deluxe said:
For drag racing you do not need to worry about what class you fit in! Just go bracket racing. No rules to meet except safety requirements. No worries about running against any cowardly cheaters. No teardowns. Just do a few time trials, put your dial-in on the window and go racing! Your 15 second flathead can win over a 11 second Corvette if you can drive good enough. Quick reaction times and consistency win races, not ultimate HP.
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I did a little bracket racing, didn't like it at all. Different strokes for different folks I guess.
 
You mean a 180 deg crank, right?

Yes, I think it would and 180's are good with 3 mains. I think that is what the Novi used.

It's said that they have vibration issues but, I don't think it would effect the flathead range of rpm.
 
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