R3 Power!

[mfg]

The authentic Studebaker R3 engine that was on display at the SNM, and later sold and installed in an Avanti, produced.....1) 335........2) 357........3) 379.....or......4) 405 horsepower when it was dynoed prior to the install.

[mfg]

No R3 experts in the house tonight?

[Warren Webb]

I remember hearing they had to hit 335 hp on the dyno before being shipped.

[mfg]

I remember hearing they had to hit 335 hp on the dyno before being shipped.

Yes that 335 was 'sort of' the advertised figure......but that isn't the answer here!

[mfg]

Any other thoughts here?

[BRitz]

405hp.

[mfg]

405hp.

You'd think it would be good for 405 HP with all that we've heard about R3's,...........but when the Myer's dynoed it , the peak HP figure was #2,........ 357!

[Geoff]

How did the Myers dyno the engine, with full exhaust and all engine accessories attached? That would give 357 net horsepower and the equivalent gross rating would be circa 400. Then again, strapped to a chassis dyno that same 357 would be closer to 280.

[mfg]

Not sure how it was set up on the dyno...it was done off the chassis....The Myers actually 'went through' this R3, (B-92), as it had sat in that crate, and then on display, for many, many years.....a WISE move!

[Geoff]

A fellow named Steve Clay owned a portable dynamometer on the premises and was charging to have your car rear-wheel "dyno'd" if you wanted...but he was so taken with The R3 Plain Brown Wrapper that he asked us to bring it back and he would "dyno" it for free! The whole procedure and readout are more complicated than it would appear.

The R3 really strained at the Plain Brown Wrapper's tethers [to the dyno] and produced 365.1 HP MEASURED AT THE REAR WHEELS with a fully "loaded" drive-train at 5830 RPM! Mind you, this is for an engine that Studebaker rated at 335 HP @5300 RPM on the test stand.

Quote pulled from this site, http://www.racingstudebakers.com/team_one.htm

This is talking about Plain Brown Wrapper's R3 in "Pure Stock Muscle Car Drag" trim, so not Myers' refreshed R3 but one nonetheless.

365.1 HP through the wheels require we add 16% (really more if we're talking about an automatic transmission not a manual, and old technology not new) so that puts us at 434.6 net horsepower. Next, we can add another 10% resulting in at least 482.9 gross horsepower at 5830 RPM.

I'm curious why this peak power figure occurs below 6000 RPM? R3s should be good to about 6800 RPM, yes? I wonder if the person on the throttle was holding back?

Edited November 25, 2015 by GeoffC312

[brad]

The R3 I built developed 405 hp @ 5800 rpm on the dyno through the stock R3 exhaust headers. It doesn't matter if you rev it to 8000 rpm or not. peak horsepower is peak horsepower. dependant upon cam choices, and engine flow capabilities. Even if supercharger boost increased dramatically, if the cam can't take advantage of it, it's useless parasitic drag.This was even with higher flow titanium valves, and a higher lift (than stock R3)Comp Cams cam. The supercharger was even modified for higher output with a better impeller. Stock R3s were pretty close to the advertised 335 horsepower.

Edited November 26, 2015 by brad

[BRitz]

405. "Prior to install"..... with Brads engine.

[64Avanti]

You have to remember that the R3 heads are not all equal. Although the drawings call for porting many or perhaps most of the engines sold by Paxton were most likely not ported. This could have resulted in a 10 to 20% increase in flow. Based on flow for an unported R3 head with the R3 cam 330 hp is about right. A ported R3 head with R3 cam would be close to 400 hp.

So was Brad's engine with ported heads or not and which "R3" cam did it have?

[brad]

The heads were ported. One can easily tell this by looking at the center exhaust port. Ported heads had combustion chamber volumes STAMPED just above the manifold mounting flange.

The Comp Cams custom grind is a 279 duration, .511 lift grind. (hotter than the 'milder'' R3 grind, but a little less duration than the 288 cam. Lift is much more important than one would think on a Stude V8.

Edited November 28, 2015 by brad

[mfg]

EXCELLENT info brad!

[ron@crall.com]

About a year before his death I had the pleasure of a long talk with Andy Granetelli about 63R-1025. When asked about how much horse power the engine produced he advised that it had never been dyno'd and that they did not promote the HP produced as the board of directors was pretty squemish about their racing activity, however he held the Riverside International Raceway 1/2 mile drag racing record and regularly beat 426 MoPar's and he figured that it would take over 500 HP to do that. He stated that he ran the car to 8,000 rpm in order to beat the Hemi's.

The engine is a prototype, it was stroked, not bored, to 299 CID. It has the competition blower. It has triple valve springs, the retainers are titanium and were obviously machined by hand, each being visable unique.The cam has the 276° part number but it appears that it may have been re-ground. The heads have the R2 part number but have been ported and polished and the combustion chamber has a significantly different shape.

[64Avanti]

Andy may have said he went to 8,000 rpm on that engine but don't run any Studebaker with standard rods and the 3.625 stroke to 8,000 rpm! You may not like the results.

[ron@crall.com]

The rods appear to have had some attention paid to them, however; as I said to Andy, "you can afford to blow an engine, I can't" I will, however; admit that in the car's youth my brother and I wound the tach past 6K until the needle hit the "T" in "Thousands" The 1-2 shift at that point was a thing to behold, as was the noise emitted.

The engine is now over 50 years old. It was last run in the late 90's. We did a compression check and verified that all valves are free and operating and planned to start it up last month but will wait until spring. We hope to have the body work done and the car back on the road in time for the meet in Providence. With the age of the components I doubt the engine will ever get on the high side of 5K again. It's significance is in what it was, not what it is.

Speaking of Providence, what is going on in this summer? Are there two meets? If so, why?

[64Avanti]

The fact that it is old will not affect how high it can rev. I wouldn't worry about going to 6500 rpm. The real problem is that at 8K rpm the big end of the rod is weak and goes oval under load. This can lead to pinching the crank and spinning a rod.

[Geoff]

You wouldn't attribute old metallurgy to an engine failure, if say RS1021 were run as Hot Rod Magazine ran her and stretched it to 7000 RPM? -http://theavanti.net/63_stepforward.html (Read as, magazine test drivers were more conservative than Andy G. was to the ol' girl).

When I was driving it in the middle and later '90s, the engine would float the valves at speeds greater than 5000 RPM. If it were ever to see 7k (or Andy's 8k) RPM operation again, at the very least it'd require new valve springs; a more thorough overhaul would be preferred. [Who's got access to jumping strings of string theory and/or time travel?]

Maybe we need to drop the oil pan and get some nice HD video documenting the crank and rods?

Edited December 1, 2015 by GeoffC312

[mfg]

63R-1025 is an extremely interesting Studebaker Avanti.................The only problem with the car that I can think of is.......I DON'T OWN IT!!!!!!!!!!!!!!

[64Avanti]

Valve float at 5K! Those must have been some really bad valve springs!

[Geoff]

The car was run hard in its early days. That engine frequently saw bursts to 7k (Hot Rod Magazine), 8k (Andy Granatelli), and wherever the "Th" of "Thousand RPM" falls on the tachometer face (Ron and Doug Crall). 1- They're springs from the 1960s. 2- They're worn from being over-worked. 3- The cam in RS1021 may very well have been reground for more lift and/or duration.

Andy had triple springs in that thing to make sure the valves operated as he needed them to, and they did. When I was daily driving the car from 1995 - 1997, that's when I'd experience valve float on those same, original, Paxton & Studebaker installed valve springs.

Like I said, if RS1021 were to see those engine speeds again, it would need a good refreshing.

Edited December 2, 2015 by GeoffC312

[Geoff]

In fact, I know that cam has been reground, at least in terms of duration. There is plenty of valve overlap present on that car, that I haven't heard about in other factory cars. There's enough overlap that it hurts its fuel economy. 1025 is in "afterburner" mode all the time, as the valve overlap dumps raw fuel out the back end. The Paxton crew didn't care, gasoline was like a dime a gallon, just dump that sh*t, blow it on through with the blower pressure. RS1021 is more suited as a race engine than as a daily driver. What's a typical R3's MPG? I bet they're still better than 1025.

So with this information, let's add it back to the conversation about the valve springs. They were run hard and they were asked to do work beyond what other Studebaker R3 valve springs did. Yeah, I think by the 1990s their metal would be a tad softer than in their youth, blasting through the half-mile with Andy, beating on Hemis, churning out 8,000 RPM.

Edited December 3, 2015 by GeoffC312

[StudeNorm]

Ok. This raises another question that may still be off-topic, but a Paxton S/C's output is rpm related, so what would the boost have been at 7k-8k rpm?

Ah-ha, another trivia bit!