Re: Convert '37 115C to straight eight?

Posted by Rusty O\'Toole On 2010/2/6 16:22:42

All kidding aside, if your stock six cylinder engine was in top shape it would have all the power you need.

You might be surprised. I know other people have been. They had flathead 6 cylinder cars from the 30s and 40s. They had the engine rebuilt and also asked about hopping up the engine, or changing the transmission or rear axle to get some more speed.

When the rebuilt engine was installed, they forgot about any other mods. The old engine had plenty of power.

Old flathead engines are foolers. They will continue to run without protest in an advanced state of wear and decay. No raps or bangs or bad manners. They just get slower and harder to start.

Another thing. The stock horsepower looks low but that is not the whole story. Those old long stroke engines do their work easily because they have so much torque and such a broad powerband. For normal driving torque in the low and middle speed ranges is far more important than developed horsepower at maximum revs.

It is also possible to get another 15% or 20% of horsepower with minor mods giving no external sign.

A reground cam, milled head, larger carb and larger single exhaust with quiet muffler will do it. The distributor can be recurved as well.

If you are a real gone hot rodder you can lighten the flywheel for whippier acceleration.

All these mods will increase performance without hurting drivability or engine life.

And it will still run fine on regular gas. But it will get about 10% better mileage.