Can this be duplicated with a 5.9 build??

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HankRearden

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310 hp at 4100 rpm 450lbft torque at 2400 rpm.

These are the published hp and torque figures of the cast iron 8.0 v10 Chrysler used in the 90's.
Having had one of these that rotted out before its time I have missed the power for towing.
But I see some of the amazing 5.9 builds published on this forum and it made me wonder if instead of building for horsepower maybe some of you much smarter than me would entertain an idea of building for something to haul the race car or boat.
 
...........Or figure out how to swap a 440 into one. No, I haven't.............

Frankly, if you are towing, there is only ONE correct answer. It is an inline six and is not built by Chrysler They are however, 5.9 LOL
 
Maybe with a 4" crank and a cam that's focused on low RPM torque. A turbo or supercharger would get you there on a gas 5.9.

I consider towing a turbo diesels job. Once you've towed with one you'll never look back but boy do you pay for them up front.
 
I built this 5.9 with torque for a truck, it pulled great.
The engine acted just like comps desktop dyno said it would.
Look at the off idle torque.

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basically torque is displacement, if it's NA or power adder and hp is how much it can displace over time. or said another way torque is one powerstroke and hp is all the powerstrokes added up.
 
310 hp at 4100 rpm 450lbft torque at 2400 rpm.
That's a hard target for a normally aspirated 318 cuber, Especially for a low-compression example that might barely crest 240ftlbs.
But here is a 5.2M with a keg intake. Notice the Torque is already up at 3200, and the power-peak is already up at 4400. And this is in a 9.0/9.2 compression engine. When you take the EFI/keg off it, you will lose that lovely torque spike.
To even get close to those V10 numbers with 318 normally aspirated cubes,
IMO, that engine will need a chitload of compression, probably specialized porting, and very specific intake/exhaust tuning.
But it should be easy with a super charger or maybe even with turbo charging, on any old low-compression teener..
power-318-gif.gif
 
Frankly, if you are towing, there is only ONE correct answer. It is an inline six and is not built by Chrysler They are however, 5.9 LOL
I got to see one of those torn apart recently. The bore looks close to 4 inches (I didn't measure it), but if it is, then, to make 5.9liters from just 6 cylinders, it would need a stroke of ~4.78 inches. That comes to 60 cubic inches per cylinder. And they only "fire" three cylinders per revolution..... Said to be very smooth.
 
I got to see one of those torn apart recently. The bore looks close to 4 inches (I didn't measure it), but if it is, then, to make 5.9liters from just 6 cylinders, it would need a stroke of ~4.78 inches. That comes to 60 cubic inches per cylinder. And they only "fire" three cylinders per revolution..... Said to be very smooth.
The "seat of the pants" torque they deliver is spectacular. It just MOVES, no fuss, no muss.
 
Cummins weigh around 900 lbs . That is a big hurdle if you have a 1/2 ton .

Aim for 450 ft-lbs around 3000 and match the gearing .
 
That cam lift sounds low to me, maybe those are the 1.5 ratio numbers.
 
OP said 310 HP and 450 TQ.

That's pretty close to the stock 5.9 @ 245 and 330, and should be relatively "easy".

Here's one (310 and 400) already built for $2500-

JEGS 3601: Chrysler Magnum 360 ci Performance Crate Engine [310 HP/ 400 FT.-LBS.] - JEGS High Performance

9.1:1 compression
  • Camshaft: Hydraulic roller
  • Advertised Cam Duration: 251 Intake; 271 Exhaust
  • Cam Duration @ .050 in.: 188 Intake; 194 Exhaust
  • Cam Lift: .411 in. Intake; .418 in Exhaust
I’ve eyeballed these packages before and I think there pretty good. It is a valve spring (if even needed) & cam swap away from a very nice mild performance engine or in this case, a tow engine.

IDK, perhaps something like a 210@050 intake duration?
It’s small enough not to need a converter change but effect the low end power a good bit.
 
Towing takes more than just HP and Torque. An engine that makes 600 hp and 700 ft-lbs for 10 seconds on a dyno does not translate into a good tow motor . Heat generation and rod angle generated stress etc comes into play .
 
OOps yur right, yeah 430torque is doable with a 5.9, but I can't see it at 2400 normally aspirated.
Sorry I screwed up.
Exactly, the OP was asking about a motor that would equal the 450 ft lb torque at 2400 rpm. To get that torque at that low of a rpm with a less cubic inches, he will need boost, and I am thinking a positive displacement supercharger or an undersized turbo that spools early would be the way to get there.
 
The thing with the Jegs engine is that the 410 ftlbs at 3000 is WFO.
As is the rest of that graph..........
Not particularly cruise-friendly.
But ya gotta admit; it has a heckuva loooong flat power curve. At 3800 it is already at 95% of peak, and the power just keeps on going and going and going, lol. Then at 4900, the rate of decline of the torque curve eases, and the power actually begins to climb again? IDK but it is significant.
 
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30 lbs of Tq. is a sizable amount more for the engine is question. I again say, the right cam will do it. Even more so due to the size of the cam in the engine as delivered. AKA = TINY!

Also! Pay attention to Mr. Vizards exhaust thoughts!
 
310 hp at 4100 rpm 450lbft torque at 2400 rpm...I would say it could be done with at 360 inches with the right parts but it would need good heads...if you use a 4 inch crank it would be a lot easier...
 
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