340 CI Studebaker V8 (R6?)

[mfg]

It's known that the special cylinder heads used on the 304.5 cubic inch R3 Studebaker V8 were actually intended for a larger 340 cubic inch V8 that never made it into production. Was this 340 engine essentially the same Stude V8 we know, but cast with larger cylinders? Were there other differences beside the larger cylinders?

[Gunslinger]

You might get a better answer over on the SDC Forum...more people there will be aware of it. At least one member there owns a prototype 340 block (I believe).

[PackardV8]

Yes, exactly the same. Since none of the prototype blocks were ever built into engines by the factory, we'll most likely never know what Studebaker planned for them.

It isn't rocket science to speculate what might have been done, as the smaller Chevrolet grew from 265" to 400" so the same enhancements would have worked for Studebaker.

jack vines

[lschuc]

Jack, I believe that at least one prototype 340 engine was running in a Lark-type car. Several years ago, SASCO owner Dennis Lambert was telling me and a friend the story that he actually was given a ride in a Lark type vehicle with the prototype engine. He related that it sounded better and stronger than any 289 Studebaker engine and pulled stronger and faster than any Avanti, even the R2 or R3 engines. There was no supercharger either. He said that there was at least the one, but I think that there probably were a few others that were built. I think most were disposed of at the bottom of the pit at their foundry.

Lew

[PackardV8]

Jack, I believe that at least one prototype 340 engine was running in a Lark-type car. Several years ago, SASCO owner Dennis Lambert was telling me and a friend the story that he actually was given a ride in a Lark type vehicle with the prototype engine. He related that it sounded better and stronger than any 289 Studebaker engine and pulled stronger and faster than any Avanti, even the R2 or R3 engines. There was no supercharger either. He said that there was at least the one, but I think that there probably were a few others that were built. I think most were disposed of at the bottom of the pit at their foundry.

Lew

Agree, Lewis, there may have been any number of engineering prototype projects which never were documented or replicated.

Having said that, the number of South Bend legends which never happened are many. We've all seen the first-hand reports of 2x4bbl '56 Golden Hawks, special ordered supercharged '59 Larks, R4 Avanti and on and on.

My bottom line is if a story can't be substantiated by three reliable sources, two of them in print, I'm not going to repeat it. Your opinions and results may vary.

jack vines

[mfg]

Jack, I believe that at least one prototype 340 engine was running in a Lark-type car. Several years ago, SASCO owner Dennis Lambert was telling me and a friend the story that he actually was given a ride in a Lark type vehicle with the prototype engine. He related that it sounded better and stronger than any 289 Studebaker engine and pulled stronger and faster than any Avanti, even the R2 or R3 engines. There was no supercharger either. He said that there was at least the one, but I think that there probably were a few others that were built. I think most were disposed of at the bottom of the pit at their foundry.

Lew

Many Avanti owner/drivers said the same thing about the 'pull' of the 400 chev small block which came in mid 70's Avantis....They'd run away from Stude R2's, at least on the low end!

[64Avanti]

This is just speculation but educated speculation. A 340 cu in Studebaker would most likely have better low end torque than either an R2 or R3. Being that the heads would have been the same as the R3 heads the maximum horsepower would have been more than an R2 but less than an R3. So it would have felt strong off the line.

The 400 cu in SBC in the Avanti IIs had bad heads and cams. They ran ok to about 4000 rpm and then fell very flat. If you have an original it needs better heads and a different cam to wake it up.

[mfg]

Does anyone know the absolute maximum cubic inch displacement limit of the Studebaker V8 engine?

[PackardV8]

The small block Chevy, with 4.4" bore centers, with aftermarket blocks, is routinely built to 454", so the Studebaker, with 4.5" bore centers and a taller deck, could easily have been built to that or greater displacement.

jack vines

[plwindish]

64Avanti is correct that will some "love", new, pistons, a better cam and some head work, the 400's will come alive. My '76 certainly did.

[PackardV8]

Does anyone know the absolute maximum cubic inch displacement limit of the Studebaker V8 engine?

Under what conditions? A street normally-aspirated sonic-tested early block can usually be built out to 353", 3.75" bore x 4.00" stroke. This requires custom welded stroker crank, custom rods, custom forged pistons. That's about $4,000 in parts and $2,000 in machine work. Then, to get the benefit of those inches, professional head porting ($2,500) a roller cam and kit ($2,500) is necessary. It would cost a minimum of $12,500 to do it correctly. Then, it would be outrun by a well-built supercharged 299".

For an all-out supercharged racing engine, especially a full-flow block, 299" with custom forged pistons (.060" overbore)would as big as I'd go.

jack vines