In a message dated 02/21/2000 6:14:15 AM Pacific Standard Time,
lsr_man@yahoo.com writes:
<< For years I thought that the 286 and 296
configurations were the biggest you could go with
a flathead, then this weekend, re-reading through
last year's Bonneville program, I noticed that
the Pappas/Stevens XF roadsster is running a 314
flathead. How'd they do that? I though that
would get into the water jacket.
>>
Dick,
No, 313 or 314ci ( 3 3/8" X 4 3/8") is very doable without hitting any
water. In 1989 I ran that combination in the XXF/GL. One could even go to a 4
1/2" stroke and stay "wet" as long as stock Ford rods were used, netting
around 324 ci. Beyond 324ci things get a little "dicey" due to the fact that
3 7/16" bore is past what most blocks will take, the wall thickness gets
pretty thin, and the Flatty rod becomes the weak-point of the system. Using
Cunningham-type rods in almost any length stroke requires grinding clearance
notches in the bottom of the cylinders. I've run as long a stroke as 4 1/4"
with Cunninghams and didn't hit water when I notched the cylinders. Whether
the block would take much more notching without hitting water is another
matter.
Another factor is cam-to-connecting rod clearance with a combination long
stroke (over 4 1/4"), Cunningham rods, and a larger base-circle cam. Kenny
Kloth in SLC has had extensive experience in that field. Maybe Wester or one
of the SLC guys could get a reading from him and post it for
us..........Ardun Doug in CA
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