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Leon
02-16-2012, 06:42 PM
Hey, I rebuilt a Stude V8 about ten years ago for my Hawk. I wanted a little hotter than normal engine so I sent my heads & cam off to a Studebaker Performance guy (who shall remain nameless). He did work on the ports, put in R3 valves and ground the cam. When I got it all back I installed to newly rebuilt short block & off I went. Well, the cam was just a little too hot- car ran rough and was didn't make good vacum. In the meantime the Performance guy went thru a divorce, went out of business and dissapeared. And sorry, I dont' have any specifics on the grind he used.

So for ten years I've driven the Hawk like this, but rarely, since I didn't like the engine performance. From time to time I've thought about finding an R1 cam and replacing. I called another Studebaker guru recently to see if he had an R1 cam he could sell me. Instead, he recommended an R4 cam. Said it was just the ticket- would work great for me.

I know that no R4s were ever built, but I guess the specs for the grind are still around. So anyway, does anybody have any input? I don't want to go thru all the trouble to install another cam that will also be too hot or cause other problems.

bezhawk
02-16-2012, 07:12 PM
There were two different cams for the R3s and R4s (same cam choices) . The milder 276 o cam...and the wilder 288 o cam.
The 288 will be just like what you are experiencing right now. The 276 is better, but maybe still just a tad too touchy for the street, and every day driving. The smaller the engine, the more a high duration cam affects the running. A 288 cam in a 350 , would be much smoother, than in a 289, and was barely tolerable in a 304.
I would recommend something like Phils (Fairborn Studebaker) R2+ cam. Something along those lines will be much more driveable.
What really wakes up Studes more than duration, is lift.

63 R2 Hawk
02-16-2012, 07:16 PM
Mine has a special "grind" from John Erb. It idles nice, has a nice, well behaved lope to it and still provides decent low end torque.

PackardV8
02-16-2012, 07:16 PM
The R4 used the same 276-degree cam as the R3. There was an optional 288-degree cam.

Since R1 cores are hard to find and R3 cores are unobtanium, consider the Iskenderian ST5 regrind. It is 268-degrees, half-way between the 260-degree R1 and the 276-degree R3 cam. Works wonderfully well on the street, has good vacuum and good idle. Best of all, it is inexpensive and can be ground onto any stock Stude cam.

jack vines