I was considering those; heard good things about them, about the cracking issue solved, and good flow. Unfortunately I have heard a little bad about them as well. The builder I talked to was a little lukewarm on them, and it sounds like the valve guides may not be so great IIRC. Will not be as great a deal if I need them reworked before they have to go in. "My" builder, or the guy I'm leaning towards to do the work, says the easy part is making the power.

Sounds like the expensive part will be the heads.

 

The cams, heads, intake and strength of the rotating assembly will dictate where the power falls flat. I could easily have a 600 hp NA Magnum. Or a lower compression blower motor with forced induction that's putting out 900 HP. Not really what I'm after. And not really comparing a supercharged sports car engine to a truck engine. Talking about putting out better power and torque than a new 5.7 Hemi at lower rpm. A bit like this:https://www.performanceinjectionequi...ed-performance.

That engine makes 475 HP at only 5400 rpm and 500 foot pounds of torque. Kind of what I'm talking about when I refer to a Magnum that won't take a back seat to a Hemi. Though I would likely settle for a something under 400 and power available where I spend more of my time in the rpm range. Not sure of what I think about the 8 speed. Am somewhat wary of it, and think it is somewhat unneeded for an engine that isn't peaky.

 

Can always just install new valve guides, though, I am real curious: what's to screw up? They are likely pressed in, and so long as the clearances are right, should last a good long time.

More gears means it's easier to keep the engine in the RPM range you really want to be in. Better power, better economy, (deeper overdrives) less pain and strain. Of course, getting that hemi and 8 speed to play nice in an older truck would be the real trick. Especially the 98 and up trucks, where friggin EVERYTHING goes thru the PCM, even the friggin gas gauge.

In the magnums, it's the intake that chokes off power above around 4000-4500 RPM. But, it's the intake that also gives it all that low-end torque. Question becomes, do you NEED to build power above 4500 RPM? I mean, it's a truck, not a race car.

 

I forget what it was exactly. Just that he didn't seem super impressed, and his group does a lot of race engines.

More gears is better as long as it's reliable. I am wary of it, and don't like the little electronic dial. I hear the new trucks can't be "rocked". Spent about $4800 getting an upgraded transmission rebuilt and installed a few years ago.

Hemis have their own issues also. Expensive to build, and more expensive to make power with. They lack a little low end torque. So I'll stick with the Magnum. More cubes, more bottom end, and some potential.

Definitely want to get more air flow through it, and that's the balancing point. A good build won't kill the bottom and mid range. Have seen a couple where there is just way more power and torque everywhere, except off idle maybe. Just for fun, here's a 606 HP build with 595 pounds of torque. It's a 426 stroker off a 360. If you look at the power figures it's making more horses than a stock Magnum peaks at, at only 3000 rpm and way more torque.

I don't really need over 600 horse, but 245 and the stock torque could stand to be improved upon. Likely my happy spot would be around 380.

 

Trouble is, there is an extreme shortage of aftermarket EFI intakes for the magnums. Seems mopar stopped making the M1, in it's various iterations, so now, finding one on the used market is your best bet. (M1 2bbl would be ideal for your purposes, but, very closely related to 'hens teeth'.....) Aside from that, there is the Hughes Air-Gap. Tends to sacrifice a bit of bottom end, but, you get better mid-range, and upper RPM power. With the correct cam/heads/exhaust combo, you could still build more bottom end power than a stock motor, without too much trouble. More cubes would make it even easier. (408)

 

The M1 sounds like it would be the one to fit the bill, but I should be able to find something useable. Hughes seems to make some good power. I'm not really sure what exactly I'll need and how the actual drivability will be by looing at dyno numbers, except when I am towing, passing or putting my foot in it to rotate the tires. I guess that's where having a good engine builder will pay off, as long as I can afford to pay! I will be talking to a couple guys and hope to find out more, soon.

I won't really miss less off idle torque if I get it all back, and then some at 1500 rpm, or maybe 2000 rpm. Anxious to see what is possible, and what is affordable.

 

Depends on your definition of 'affordable'. One member here spent over 5 grand on his 408 build, and it still wasn't finished.

Could also go with a slightly higher stall converter to make sure the engine gets into the power band nicely at zero MPH as well.

 

Any thoughts on high compression engines needing 92, vs. one that will run on 87? Initially I was thinking that it would be more money to run a high compression engine; but then it occurred to me that the higher compression engine is more efficient.

And also maybe some additives in big containers might be cheaper to raise the anti knock index than premium fuel?

 

Ha! Yeah, I've been in contact with a guy that spent about $11 000 on his, and his buddy spent about $10 000 on a crate engine. I'm kind of counting on not needing "race everything" and I know a good cast crank will do fine for an >500 hp engine. I'm hoping to be able to get a good performer with none of the stock weaknesses for about $5000 just for the engine. Little, weak Canadian dollars. Should have done this crap back when we had a good PM and were at parity.. Not stuck on name brands or replacing things that I know are good yet. My alternator works, my oil pan is fine, and my water pump is just about new.

Realistically it's a 20 year old truck, that I have way too much money tied up into. But I like it, and am planning on running it for several more years at least. Way cheaper than a new truck payment for 7 or 8 years, or however long they are letting you "mortgage" one now. Plus, anything else, I'd have to start upgrading. Not that I'm completely done with this one, but it has a lot of little improvements, like the stereo, and big bus heater that I tied into the cooling system. The interior is good yet, and the body is not bad.

Could do, but I want to keep it docile and be able to idle around.

 

So I only have one chance to do it the way I like it. Messing around with stuff shortly down the road, would be a no go, and an aweful tough sell in my household.