It's got good torque and low horsepower, almost like a diesel engine. All of it's power is in the low end. It redlines much lower than a modern engine. I'm not the most educated on engine technology of that era, but its is the low horsepower/higher torque ratio normal for that era?

 

It depends on a lot of things. The real thing you want to study on an L98 engine if you're fascinated by it's torque to HP relationship is the intake manifold. The cam is partially responsible (as in any case) but the big thing is the intake. If you are a math nerd read this and understand the equations towards the end of it and you'll have a pretty good understanding of what's happening and why. Keep in mind that the head's runners add about 6" to the total of an SBC intake manifold's runner length. Intake and exhaust tracts have huge impact on where you make power in the RPM range. Camshafts do too, but in this case the defining characteristic is certainly the intake and the cam would be a secondary player.

https://grapeaperacing.weebly.com/up...ionsystems.pdf

 

Yeah alot of stuff seemed to make low hp higher trq n that era. Fox body mustang 5.0 was 220’s hp 300 trq

 

That is a great paper. I saved it to my library! To visualize this, I think of a long garden hose. When I shut off the hand nozzle to stop water flowing through a long hose there is a big hammer effect of the momentum of the flowing water coming to a sudden stop. This hammer is a pressure wave. If I time the opening and closing (pulsing) of the nozzle correctly, each pressure surge of water at my end (the nozzle) can actually increase the pressure coming out of the nozzle at each pulse. In this case, the nozzle is the intake valve and the water is the incoming air, the hose is the intake runner and the "tuned port".

 

I'd say that it was typical of most american engines of all eras up until the mid to late 90's to be that way. I'm sure I could list things and still miss many potential factors but one reason is american engines often weren't made to rev as high as current engines nor international engines of their time. And engines that could rev here often weren't rated at the rpm they could achieve.
Drac0nic's post shows the exact reasons tpi was so recognized for these factors but I don't think it's anything inherently special with the L98 over any other competitive engine.
Cool nonetheless.

 

TPI’s were the best truck engine Chevrolet never made.

Tall Y & F body rear end gears as the fulcrum, with a big long torque lever of an L98 or LB9 to get all that mass moving & still get respectable gas mileage.

 

One of the guys here (v8astrocaptain) had a 305 TPI Astro Van (I think it ran swirlies even, TPI+swirlies are another arguably interesting combination for a truck but that's an aside) and he was getting 25mpg in an m-van on the highway with 3.73s. With the 4.3L I typically got 22ish with 3.42s or 3.0s.

It wouldn't burn the world down by any means but it had to have been a great all around combo for something to just haul yourself around and goof a bit on the street, perhaps even some light to moderate towing especially viewed within the lens of time it was made in.

 

I think they are the best looking engines ever. They were so different from anything else when they came out i was impressed as a child when the 85 Irocs hit the street with their "octopus" engines as my Dad called them.

 

The 350TPI in my 89' GTA had swirl port heads with the stock L98 cam (engine was replaced by a previous owner). It was a torque monster with tons of midrange power, but horsepower fell off very quickly above 4000rpm. Would have been a great truck motor.

As was already stated, back in the 80's when port injection was introduced, pretty much all manufacturers were designing around a lower RPM torquey motor. This was the beginning of the steady improvement in performance up to where we are now. I imagine their goal at the time was to boost the torque output at lower RPM so the seat of the pants feel of a bigger or higher performance motor was there, but the tradeoff was a sharp decline in horsepower at higher RPM. Even the Multiport 2.8 V6 that GM put in everything back then was a little motor compared to just a decade earlier, but had a reasonable amount of torque to move all of those grocery getters.