Re: V8 Engine Idenification Help

Posted by Jack Vines On 2009/8/2 12:15:22

Welcome to the club! Your R5 is the short box 1/2t, correct?

FWIW, I have a Packard V8 ready to go into my '55 E12 Studebaker 3/4t truck. Let's keep in touch as we build along together.

1. The 374" has 10:1 compression ratio which is too high for today's fuels if you plan to use it as a truck and pull a load. Running unloaded, with premium fuel and a custom ignition advance curve, you might get by.
b. The '55 352" heads have larger combustion chambers and can be retrofitted with '56 valves if you feel it is worth the effort. Not sure I would if the '55 heads have good valves in them.
b. The '56 combustion chambers can be enlarged by hand grinding to lower the C.R.
2. Which transmission do you plan to use? The R5 is geared far too low for the Packard. You'll need an overdrive and the OEM Borg-Warner T85 is perfect. Do you have the standard shift bellhousing and flywheel?
3. What are you going to do about the brakes? The Packard, properly geared will quickly outrun the little 1/2t Stude brakes. Since the rear axle has to be changed anyway, better brakes back there come along with the deal.
4. The 374"s usually had dual exhausts. Since the C-cab has the fuel tank on the driver's side of the driveshaft, it will be easier to fit a single exhaust down the left sid, so find or order the single kit. Use a 2-1/2" or 3" muffler and tailpipe and you won't notice any horsepower difference in normal driving.
5. The tapered axles in your rear end won't last long under Packard torque. Plan to upgrade to flanged axles or replace the entire rear axle with a stronger one. If you're not using an overdrive transmission, you'll want rear gears around 3.07 to 3.54.

thnx, jack vines