Flatheads: Whats the most HP you've seen/heard?

WOW, it is flat amazing what can be done to a banger!!!

 

Dunno about the nunbers but it would be very interesting to see Big Jungle Jims, Moon injected Roadster take to the rollers. How about it Jimbob, I know you're going to read this?

 

Ron Main and Dick Landy put "Flatfire" together. (along with a WHOLE WHACK
of other people! )
The objective was to make a "flathead" (one engine) go over
300 MPH at Bonneville. (they did it! )

More details here >> www.flatfire.com

Check the "What's New" box for the final speed.

 

The Tardels have the strongest flathead on the salt (a proven fact) I don't recall the exact number although someone told me recently but it is somewhere over 300 hp.

That is a blown and injected, major hybrid flathead.

There is one proported to be healthier than theirs by about 30-40 hp recwently dynoed but it has been in the wind yet.

 

This a Mark Kirby built 350 horse 327 cube flatty.

 

The installation was in process when these pictures were taken, so "some assembly is (still) required."

Mike

 

Flatfire. www.flatfire.com

 

I assume by now you have figured out there is no way a naturally aspirated flathead on gas is going to make 400 HP. My flathead was on a chassis dyno in 1968 and registered 124 HP at the rear wheels. It had stock EAB heads, no port or polish, no relief, 3 3/4" stroke, .060 over bore, single two barrel Rochester 2GC adapted to a stock manifold (hadn't figured out the Merc manifold trick yet), Isky 1017 cam, stock valves, stock distributor with locked advance, home made headers, no port dividers, balanced and blueprinted. I remember we were disappointed with the numbers, but in hind sight, that was a pretty stout motor for what it was.