15k BTU on 2200 watt generator

drsteve wrote:
But at the same time, Chevy engineers get 650 HP and 650 lb-ft of torque out of a pushrod activated small block V8 that passes emissions specs and will run for many thousands of miles, even if the owner has a lead foot.

When they engineered this engine, no doubt they knew going in they were constrained to lower RPM's due to the OHV design and designed it accordingly. Based just on the even up HP/torque numbers (650/650) it's obviously a relatively low revving engine. When the torque numbers get significantly higher than the HP, then the max rpm's drop accordingly (i.e., diesel). When the HP numbers become a multiple of the torque rating (F1), then you're talking massive rpm's and a mandatory DOHC configuration.

TomG2 wrote:
Now we know how a 2,000 watt generator can run these big air conditioners. Crank them up to 12,000 rpm. OHC models only.

Good idea! Used to own a CBR600f4i. Words can't describe how awesome it sounded pushing DOHC's at 12,000++ rpm's! If you really like rpm's, try a turbine generator. They absolutely and literally scream!

otrfun wrote:

drsteve wrote:

otrfun wrote:

3 tons wrote:
I can still recall the original cast iron, OHV Ford GT 40’s of Le Mans fame walk away from the high revving, sure to win OHC Ferrari’s

Yup, pretty interesting piece of racing history there. With that being said, got to wonder why modern-day Le Mans, Indy, and Formula One cars continue to use OHC engines.

High RPM power, of course. Modern F1 uses 1.6 liter V6 turbo engines, Indy 2.2 liter V6 turbos. Not much low end power to be had with that configuration, so they rev 'em to 12,000 RPM. No pushrod motor will do that.

Agree. The pushrods on an OHV motor would turn into a pretzel at 12,000 rpms--lol!

But at the same time, Chevy engineers get 650 HP and 650 lb-ft of torque out of a pushrod activated small block V8 that passes emissions specs and will run for many thousands of miles, even if the owner has a lead foot.

Now we know how a 2,000 watt generator can run these big air conditioners. Crank them up to 12,000 rpm. OHC models only.

drsteve wrote:

otrfun wrote:

3 tons wrote:
I can still recall the original cast iron, OHV Ford GT 40’s of Le Mans fame walk away from the high revving, sure to win OHC Ferrari’s

Yup, pretty interesting piece of racing history there. With that being said, got to wonder why modern-day Le Mans, Indy, and Formula One cars continue to use OHC engines.

High RPM power, of course. Modern F1 uses 1.6 liter V6 turbo engines, Indy 2.2 liter V6 turbos. Not much low end power to be had with that configuration, so they rev 'em to 12,000 RPM. No pushrod motor will do that.

Agree. The pushrods on an OHV motor would turn into a pretzel at 12,000 rpms--lol!

otrfun wrote:

3 tons wrote:
I can still recall the original cast iron, OHV Ford GT 40’s of Le Mans fame walk away from the high revving, sure to win OHC Ferrari’s

Yup, pretty interesting piece of racing history there. With that being said, got to wonder why modern-day Le Mans, Indy, and Formula One cars continue to use OHC engines.

High RPM power, of course. Modern F1 uses 1.6 liter V6 turbo engines, Indy 2.2 liter V6 turbos. Not much low end power to be had with that configuration, so they rev 'em to 12,000 RPM. No pushrod motor will do that.

3 tons wrote:
I can still recall the original cast iron, OHV Ford GT 40’s of Le Mans fame walk away from the high revving, sure to win OHC Ferrari’s

Yup, pretty interesting piece of racing history there. With that being said, got to wonder why modern-day Le Mans, Indy, and Formula One cars continue to use OHC engines.

I can still recall the original cast iron, OHV Ford GT 40’s of Le Mans fame walk away from the high revving, sure to win OHC Ferrari’s

twodownzero wrote:

otrfun wrote:
No, there's nothing wrong per se with an OHV engine. OHV is fine for lower RPM applications like the lower revving, high torque truck applications you speak of. However, you'll rarely see OHV in high-rpm applications. An OHC design has a lot less moving mass in the valve train assembly (vs. an OHV design) which allows for more efficient, accurate control of the valves at higher rpm's. This is the reason why the vast majority of cars on the road on the road today use an OHC configuration. If OHV was a better design I assure you car manufacturers would use it---but, the fact is they don't.

You mean like America's flagship sports car, the Corvette, the best bargain in its performance class anywhere on Earth, which has been OHV for almost all of its existence, including what are unquestionably the best performing Corvettes ever made (those in the last ~20-25 years?

There might be hypothetical benefits to OHC, but they sure don't seem to show themselves in real life.

I was waiting for someone to find a loophole or two--lol! Congratulations! Granted, GM may feel there are no advantages to using OHC in the Corvette. However, common sense says the other 98% of cars (to include exotics) on the road that do have an OHC configuration, were not the result of manufacturers and their engineers being hoodwinked into using it for "hypothetical benefits"--lol! If you're saying they were hoodwinked, it would make for one helluva conspiracy theory---would love to hear about it.

Chum lee wrote:
"What is better about an OHC design?"

Among other things not already listed, when you have a DOHC (or Dual Overhead Cam) design, it allows both the intake and exhaust cams to be timed differently (varied to each other) at different RPM's. Honda's VTEC engine to name one. That option allows the engineers to optimize the valve timing for the entire range of RPM's allowing the engines to generate substantially more power with minimal flat spots in the power curve. That's for complex high performance engines which typically generators are not. OHC's also make it easier to have 3, 4, and 5 valves per cylinder which can be done with OHV engines, but not as easily. Now, . . . back to your regularly scheduled program.

Chum lee

So you're saying variable valve timing doesn't exist on OHV engines? Where did you get that idea?

Pretty sure the Cummins in my Ram also begs to differ with your latter point. Cummins has been making 24 valve B series engines for over 20 years now.

OHC is not a newer design, either. It's existed for just as long as OHV.