Operating RPMS?

[Gunslinger]

Cheap A$$ Studebaker Owners

[(S)]

Many of us who have had original engines have seen those stamped numbers. They are not what the appear, those numbers are stamped .025 or .035 but that is NOT what they they mean . Dwain has it right, except I do not recall the digits and all the zeros. Here is what I recall:

Those numbers are more like .00025 and so on and are what the VARIANCE is on the whole cylinder/ top to bottom. Bores were checked, marked and the closest fit piston was chosen to match it.

Pistons and bores were carefully measured and matched to the best fit. This is almost impossible to check without some very specific tooling and devices, made to measure the whole cylinder at once. (not a simple bore / taper gauge- a very exotic one) Your engine is probably fine, and probably stock bore size -- you will see this if you check it carefully.

I forget where I did eventually find this info, but it is in the books, or parts notes somewhere, and have learned to ignore those numbers until I check it myself.



These engines will rev until valve float or an oil line failure, or red and blues in your mirrors. 3,500 RPMs and below is very safe and up to 4,600 in short bursts is fine to blow out all that carbon. ( officer)

[mmagic]

Out here most of I-25, I-70 and I-80 cruises at the 75+ speed limit. I-25 north of town runs 90 right lane 4:00 to 6:00 AM. It looks like the Speedster with a 259 4bbl, manual/OD, 4.27 would run 75 at 3150 RPM and could actually cruise keep up with traffic.

I'm glad to be wrong on those piston numbers !

[JimC]

...Tires although 12 years old are matched with good tread and no visible cracking or rot.... another reason to keep the speed down.

That would leave me mighty nervous. I've had a tire half that age blow out on me on a modern car, and even with several more decades of safety engineered into them, even that scared the snot out of me!

I think even if you bought a cheap set of tires, you'd be better off than continuing on those old ones. Just because you can't see cracking or rot doesn't mean it's not just below the surface.

Back to the original question phrased a bit differently... Is it safe to assume that 2,500 to 3,000 RPM is a normal comfortable top highway driving range for the 259 in the Speedster?

Probably so. The 259 in my Lark is somewhere in that zone going down the interstate, if I recall. Of course, the terrain (hills or flat) along with variables like your differential and transmission will have an impact on that too. These engines are pretty beefy though, I imagine they could go all day at 4,000 and still be happy, at least so long as you're feeding 'em regularly.

[Corvanti]

That would leave me mighty nervous. I've had a tire half that age blow out on me on a modern car, and even with several more decades of safety engineered into them, even that scared the snot out of me! I think even if you bought a cheap set of tires, you'd be better off than continuing on those old ones. Just because you can't see cracking or rot doesn't mean it's not just below the surface.

totally agree!!! even going at a slow speed, if one of those tires "let loose", there's a good possibility you will sustain body damage to the Champ, or the vehicle behind you, or worse...

[Dwain G.]

As Mike G. said, those numbers stamped in the block do not represent what one would logically think. They are actually the last two numbers of the bore size to the ten thousandths. So on a V8 35 really means 3.5635. Supposedly the numbers run from 25 to 45 and never vary more than .001" on any one engine block.

[dtracy]

I'm remembering the numbers stamped on the pistons ranged from no notation to several in the .025 to .035 range and at least one North of .050! As my intent for the Champ was a low cost rebuild to learn the anomalies of Studebakers and it has the same drive train as my Speedster and no title low mileage '63 in storage driving it as is made the most sense. Total investment including purchase, paint and mechanical was under $5,000. Tires although 12 years old are matched with good tread and no visible cracking or rot.... another reason to keep the speed down. Did attempt to swap the Speedster tires/wheels on to the Champ and discovered they are not 5 on 4 1/2".

Back to the original question phrased a bit differently... Is it safe to assume that 2,500 to 3,000 RPM is a normal comfortable top highway driving range for the 259 in the Speedster?

Which car had the drive train changed out, the Speedster or the Champ?

Dave.

[JoeHall]

Out here most of I-25, I-70 and I-80 cruises at the 75+ speed limit. I-25 north of town runs 90 right lane 4:00 to 6:00 AM. It looks like the Speedster with a 259 4bbl, manual/OD, 4.27 would run 75 at 3150 RPM and could actually cruise keep up with traffic.

I'm glad to be wrong on those piston numbers !

A Stude V8, properly geared (i.e. 3.07 or numerically lower), is capable of doing 80 MPH all day long. But MPG will suffer, and at prolonged RPM above 3000 the motor will push more oil, mostly via blow-by.
MOST important is safety. If you anticipate driving it 70-80 MPH regularly, make sure you: install shoulder belts or at least lap-belts; firm up the suspension; use good shocks; have good tires, and install a brake system, i.e. modern discs.
The life you save may be your own.

Since 1985, I have driven Studes over 500,000 miles. Though yesteryear, I was guilty of many thousands of miles at 75-80 MPH, speeds in excess of 80 MPH are "pushing it" in a Stude under any circumstances. Actually, 65-75 seems much safer, and most Studes are happier at those speeds.

[mmagic]

Dtracy... Both currently have original drive train. Speedster will likely get the drive train out of the '63 in storage as it only has 23,000 miles. All 3 have 259 manual w/OD. Will need to swap OD case from the '63 as the Speedster has short tail and 63 has long tail. Yesterday on Speedster flushed differential, did rear brakes and picked up dual MS. Next get the Turner parts and rear wiring harness ordered, apply chassis black to frame, instal brake & fuel lines and reinstall control arms. Should have a rolling frame sans engine/transmission with the hard to reach items attached shortly.

I'm building this like a house.... from the ground up foundation first, then body and paint, engine and transmission and finally interior. If either or both engines are beyond salvage when I get to them there are many other options. If I focused on engine transmission today it would be near impossible to build the foundation later without retracing a lot of steps. By changing course and dropping frame a number of items originally scheduled for later will be done now saving a lot of time due to accessibility.

I don't know how you can do a restore without a Gantt chart! If I don't build it on paper first I'm asking for a lot of wasted time later.

It's a shame to part the '63 Lark as the factory paint is still good on the underside all the glass is good and body is straight even though the soft parts are dust! But the Speedster will be virtually a new car with value and the Lark with the same investment would be worth a quarter as much.

Yes Joe it will get seat belts... Without a roll bar I'll forgo full racing harness.

[swvalcon]

Back when most of these cars where built piston clearance was a big deal because they where not machined as close as they are today. Today you can take almost any box of pistons and if their marked .030 and you bore it right to 30 over they will work just fine.

[thunderations]

One should remember that the factory build Engines that had big cams and superchargers to make horsepower. They did not need to do that if the plan was to only turn 2000 to 2500 RPM. Don't be scared, press on that pedal on the right and have a little fun. *NOTE: If you plan to have this fun, make sure you have brakes and steering to go along with it. My dad, God rest his soul, always told me that we can always make it run faster, but let's make sure we can stop it first.

[mmagic]

thunderations--- First thing I did on the Champ was the brakes.. before I even knew what shape the engine was in. On the Speedster I'm switching to Turner front discs and dual master before I even know if either engine is any good or which Studebaker engine I will use or even if I default to a mopar or heaven forbid a GM product! As your dad said, I want to be sure I can stop before I am sure it will go.

I grew up driving my dad's '55 President.. pulling trailer with it and in general keeping my foot in the 4 bbl at $.25 a gallon gas. Oh the tales !!!! Oh talk about stop.... that Studebaker had hand controls augmented by a second master cylinder driven by an air brake cylinder in the trunk! With one pull of the lever you could flat side 4 tires simultaneously! Then there was the skunk that I hit and forced to unload directly into the passenger side vent.... just the mention of that event creates aromatic sensations.

What I don't accurately remember is the speeds I actually drove it at. In any case my hope is to build the Speedster in a way that I can comfortably drive it on today's freeways at today's speeds.. I want the result to be a high driver that I can drive 10,000 miles a year and that starts with the brakes not the horsepower.