just thinking ahead, if i were to build a budget street motor, what would be the best magnum combo using 318 or 360 stuff? would there be much benifit of swapping one set of heads to another? im thinking of building something with a 4in crank, either a 390 or 408. heads will be stock with a very mild clean up done by me, stock cam/valves. unsure of intake,probly stock. leaning towards fastman TB and efi controlled by megasquirt....
purpose of the build would be max torque down low in the rpm range

 

I would say use as much 5.9 stuff you can. But according to the numbers you should use the 5.2 heads. And I think the 5.2 cam was better. Check all the specs here. http://dodgeram.org/tech/gas/specs/index.html

A 408 would be sweet! Now 408ram I think would be the best person to tell you more about that build.

 

you could port you stock heads but it is not really worth the money, if you want power gains you will need to go with an R/T head(the actual mopar r/t heads, not off a dakota r/t) or the aluminum edelbrock heads. but for just low range torque a truck cam and a few minor mods should be good

 

thx for the link Crazy! the 318 does look like it has better heads. i wonder why they did that? bigger valves than the 360 head and more lift too. damn, there goes the idea of buying a spare motor and building it while im still driving the stocker as i would need parts from 2... but as far as that goes i wonder how much more hp a 408 would make with 318 heads vs 360 heads? or a 390 with 318 heads? im guessing its really close. maybe ill just build up a 318. finding one may be cheaper too.
checking out pistons, i think i would go with Keith Black. they have stroker pistons so you can use stock length (in my case just plain old stock) rods. they come .030 over (390 with the 4in crank), .040 over and .060 over. all the same price. i would get the .060 over as it makes the stroker a 396ci. thats big enough for street duty on a budget my buddys 350 chev wouldnt know what hit it lol. anyone know how big the combustion chambers are in a 318 head? 60 or 68cc? also how high can the CR go? around 10:1 on pump gas? (highest stuff we can get here is 91 octane) my bike has crazy CR(13.5:1) compared to the truck and i run nitrous. 190 hp plus 90 hp of spray on 91 octane. gotta love an aluminum pent roof combustion chamber with 4 valves
as for porting it would just get a clean up/port match. that just takes time as i do my own work, so no real cost to it. im not building a revver so huge flow numbers arent really needed, maintaining good port velocity at low rpm would be the idea. im no expert on it, but i have a bit of the concept down

 

The book that i have said that the stock production head can take a 2.02 and 1.625 valve in stock head. This should be cheep enough to install new valves when you do your port work. If I was building a street truck all over again I would have spent money on other things like a turbo. I think you will get more bang for buck if you get a stock 318/360 and put some boost on it and not worry about building a stroker. Mine runs good but I think it needs some boost.

 

i am glad someone agrees about the turbo!!! thats what i am wanting to do to mine next.

 

From what I have seen and the money that I have invested in a 408, I would have been better off with a turbo on a 5.9 and a good tune with a cam, intake, head studs, some good pistons (maybe), and girdle and go for it. I would not even change the crank and rods. They should be good for 500hp. Just make sure you don’t have any detonation issues and you would have one great street fighter or just one bad off road power plant with gobs of low end torque with the right setup.

 

i can build budget a 396 for probly a grand(not counting buying a spare motor). i assume it would be a lot more for a turbo or supercharger setup, but i would love to be proven wrong! how much boost can stock pistons take? or should i drop in a set of forged low cr pistons? any details or info you have, plz let me know!

 

I think stock pistons could handle around 6psi which that would give you more hp than doing a lot of engine building. I think if you want best bang for buck then start looking for a stock 360 and dont change anything. Try to find you a used turbo, waste gate, and blowoff valve somewhere around a T56 to a t60 and let her rip. The only big deal is you would need to fab all your own piping because i dont think you will find a turbo system for a dakota. I would only put it under the hood. I am not one who likes the rear of truck mounting system. If you dont have the equipment to build the system then you will be better off building an engine.

 

thank you for the info! i definately agree about under the hood, even with wrapped pipes you loose out on power with a turbo out back. i have lots of room under the hood for everything as i gave it a 6 in body lift. i could make the turbo headers and the piping, thats just time and buying some u bends ect. twin turbo would be nice, but probly more work for not much gain (if any) on my budget unless i can find 2 smaller turbos for a good price... i havent delt with turbos first hand, but i have the basics down(mostly from bike stuff). since im looking for low end, i would want something closer to the t56 than the t60 right? any idea where i could find a used one? (makes or models that have them ect??). what about an intercooler? maybe i should start a turbo thread?