R3 Power!

[ron@crall.com]

It has been too many years to remember, perhaps my brother does. It was a lot more than the 5-6lbs boost that I often hear. As I recall the dash gauge showed to 10 Lbs of boost.

It was high enough that Paxton added 2 gauges under the radio, fuel pressure and supercharger pressure. When asked, Vince explained that if ever the blower produced more pressure than the fuel pressure, the engine would immediately lean out with catastrophic results. When being raced, those were monitored very closely.

I'll take a picture of those gauges and post it in a few days.

When talking to someone that knew a lot more than me about how engines develop power, perhaps Jim Pepper, it was stated that eventually it didn't matter how much pressure was available, other delivery dynamics would limit the useful amount, however; I doubt that those dynamics were known back then.

[Gunslinger]

Without being all that knowledgeable on superchargers...my only knowledge is general...but since output is related to rpm's, in a Stude engine not highly modified, I think the valves would start floating long before the rpm's got high enough to cause manifold pressure to get beyond safe specs. If a waste gate or air bleed valve is present it would also keep boost from reaching too high a level.

I think Paxton and Studebaker engineered the boost to where they thought it could be within safe limits, even if there was more boost to be had. They had to provide a warranty on the R2 engine even though the R3 came without one.

Edited December 7, 2015 by Gunslinger

[ron@crall.com]

RS1021 has been pretty highly modified by Paxton. It had triple valve springs and custom made lightweight retainers. There was no waste gate or other provision for dumping excess pressure. Considering the size of the Paxton parts bin at the time, the thought of blowing the engine up was probably not too high on the list of concerns.

The thought of a Studebaker engine achieving 8,000 rpm was outside of my wildest imagination, when Andy said that he used 8K when racing it I asked him to confirm that he said 8k. He stated that at that RPM he could beat the Hemi's in the 1/2 mile.

[Gunslinger]

I can believe it when Andy said he could beat the Hemis in the 1/2 mile. I think the torque supplied by the Hemi cubic inches and breathing would take the R3 in the quarter mile but the boost of the R3 would make up for it as the distance increased. Of course...we don't know some variables...the rear axle ratio of each car, power/weight ratio of each car, etc.

Hemis were not always at their best drag racing...they were intended for NASCAR racing...not the same thing as drags. Stoplight-to-stoplight, everything being equal, a 440 big block Mopar could beat a Hemi as the wedge was better for that kind of racing.

Also...was Andy talking about the 426 elephant or the earlier hemis? I would assume the elephant as they and the R3 were close contemporaries.

Basically...I think the R3 needed the extra quarter mile to beat the Hemi.

[ron@crall.com]

On the west coast NASCAR in the 60's was a non-event, but drag-strips were everywhere. Locally we had the Fremont drag strip. My next door neighbor had a Ford with the factory drag pack, and the guy living behind me on the next block had a rail dragster. It was very much like American Graffiti. I used to eat lunch at the same Mel's Drive In in SF that was in the movie. My best friend's dad owned Ben A Begier Studebaker Packard Mercedes in San Leandro, and after production ended I did some counter work for an Oakland dealership, Milton Motors, that sold Studebaker parts and an occasional Avanti II or used Hawk.

The best car was the first to the end of the strip. There were lots of big blocks that got lots of respect, but the 426 Hemi was top dog.

No Stude had enough torque to compete in the 1/4 mile, even though PBR is doing a fantastic job at doing so, but allowed to wind up the engine like no one in his right mind would do, Andy apparently did do it in the 1/2

[Geoff]

… When talking to someone that knew a lot more than me about how engines develop power, perhaps Jim Pepper, it was stated that eventually it didn't matter how much pressure was available, other delivery dynamics would limit the useful amount, however; I doubt that those dynamics were known back then.

I tinkered around in Desktop Dyno software, oh four years ago anyway, trying to emulate an R3 Studebaker engine. What I found was increasing supercharger pressure from 8 PSI to 14 PSI didn't have an appreciable effect on the power numbers. That told me there was already enough boost "knocking on the doors" to be let in. Doors? Valves! Ah, I will check there. When I increased the Studebaker 1.875" intake valve to 2.02" (I figured the 1.625" exhaust valve was fine) WOW! That did it! 8 pounds of boost with larger valves netted better results than 14 pounds of boost with 1.875" valves. We know, as large as the Studebaker block is externally, room internally is at a premium (like the dream of a 4" bore). It's possible the hang-up in valve size was known then but what could they have done?

It was at the national meet this summer, in our talks with Jim Pepper; he mentioned the valves as a choke point and that jogged my memory.

[64Avanti]

It is not the valve size that is important it is actually the flow capacity. In the dyno software if you put in flow numbers at a particular valve size and then change the valve size the program scales the flow up based on the increased valve size.

Of course the Paxton blower will never reach 14 psi. The program also looks at the temperature affects and that may be why you don't see any increase in power at 14 psi vs the 8 psi.