Posted by Dave Speed on Saturday, October 30, 2004 at 8:19PM :
In Reply to: Re: Pressurizing A Flathead posted by RDavis on Saturday, October 30, 2004 at 1:28PM :
Funny you should ask. There are a few folks still uilding period hot rods; mostly old farts.
I've fallen in with bad company and am building a mildly rodded flatty for my PW.
This is not the TV show bullshit where they drop $15,000 "crate motors" and spend money like it is water. But rather more fun I think.
For a max build they tell me to go for a 265 with forged pistons; I'm told they can be made to run at 6000 rpm. At least for short periods.
But drag racing a Flat fender is not my thing. My goal was 3600 rpm cruise for hours at a time with a vintage engine at a reasonable cost.
To achieve this goal, I've been advised to do a blueprint rebuild on a long block (251) engine. The long block was chosen for full flow oiling, centered connecting rods and a shorter stroke (tho a 4 1/2" stroke can hardly be considered shorter), and, of course, cubic inches. The 65 is too difficult to get parts for these days.
So we boil and inspect the block, then deck the blockand line bore (hone) the crank journals. At this time I'm in for thirty over pistons on NOS rods all balanced to 0.1 gram.. Jury is still out on shot-peening the rods, but probably not needed for this build (Chrysler had the best rods of its day).
Chrome rings and Clevite bearings fit to newly machined surfaces. Still waffling on the head cut; gas quality down here is iffy and I don't wqant to buy premium all the time. This will probably limit it to a 40 thou mill.
George Asche is grinding me a cam for a little better breathing. I'm going to relieve the intake and exhaust ports, but they say that is not a lot of help.
Trying to decide between the Asche dual carbs / exhaust setup and building a custom one of my own. I've got 3 - 1 1/2" SUs sitting in the shop and remember the old XKE setup fondly ... Headers are a larger problem, but anything is doable given time.
The experts say not to mess with the valves (as in trying to put in larger valves) other than ensuring they meet spec and have a clean valve job on hardened seats and good guides and new springs.
All accessories (water pump, oil pump, alternator, starter) have been renewed while waiting for other matters to resolve.
I might go w the Pertronix ignition just for the hell of it, but don't know if it is going to help much power wise. An oil cooler will be fitted; Mobil 1 will be used after breakin.
I have photos and will drop it on a web site when I get into something sexier than parts cleaning and eBAY haunting... Parts are out all over being pampered.
Dave
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