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Angryman

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I am getting ready to build the motor for my Duster and have some questions. Sorry if this has been covered elsewhere but didn't really find the answers I was looking for. I have a 5.9 Magnum bottom end I will be using. I picked up Speedmaster aluminum hydraulic roller assembled heads and intake on the Black Friday sale. I will be dropping them off at the machine shop to get looked over. From reading here it looks like I may need to swap out the supplied valve springs. Any suggestions on which Hughes kit to use? 111P? I called Oregon cam and after talking with them they suggested kit 1990. 224/230 @ 50 & .5101 lift. Any other suggestions on cam? Now for the real question. I have been reading up on oiling the heads but nowhere do I find a parts list. Wondering if I use the stock magnum lifters and pushrods and the PRW/Mancini/Comp rocker kit is that it? Or are there parts I'm missing.
 
224/230 @ 50 & .5101 lift. Any other suggestions on cam?
It all depends what you trying to do, that's on the top side of an RV cam and the bottom end of street strip cam, right in the middle, above that you really start moving torque up the rpm band trading bottom for top and stall gears etc.. becomes real important.
Now for the real question. I have been reading up on oiling the heads but nowhere do I find a parts list.
Wondering if I use the stock magnum lifters and pushrods and the PRW/Mancini/Comp rocker kit is that it? Or are there parts I'm missing.
Probably have to make some calls to these companies to find out 100%, please post your findings I'm interested in the results.
 
It all depends what you trying to do, that's on the top side of an RV cam and the bottom end of street strip cam, right in the middle, above that you really start moving torque up the rpm band trading bottom for top and stall gears etc.. becomes real important.
I am just trying to build a nice hot street engine. 400-450 hp would be nice.
Probably have to make some calls to these companies to find out 100%, please post your findings I'm interested in the results.
I will make some calls and see what they say.
 
I am just trying to build a nice hot street engine. 400-450 hp would be nice.

I will make some calls and see what they say.
you'd be right about there with the combo, probably just a hair under 400. to get that 450 you'd want more cam, maybe some porting on the heads and squeak some more compression if you can.
 
When you make the call, ask about oiling the rocker via the pushrod. lA rockers are not normally oil this way and the rocker must be able to be pushrod oil feed by design.

PRW & Comp are the only two rockers I know of off hand that allow pushrod oiling. I’m sure there’s others. You will need a new pushrod due to the OEM Magnum pushrod not being the correct length.
 
you'd be right about there with the combo, probably just a hair under 400. to get that 450 you'd want more cam, maybe some porting on the heads and squeak some more compression if you can.
Any suggestions on a cam?
 
Probably have to make some calls to these companies to find out 100%, please post your findings I'm interested in the results.
I emailed PRW and there response was "guys have done it". With stock magnum roller lifters, oil through pushrods and their rockers & shafts I "should" be okay.
 
Any suggestions on a cam?
uhh... bigger-er?

i'm sure that somebody here on the forum is running a combo and has the recipe but i'll throw out a very unscientific WAG on it. something mid .500 with duration at about 230.

the caveat here that you can't go more than .550~.560 lift on stock pistons (note: that is total lift with a stock 1.6 rocker), and if you change your head gaskets for more compression or have any other parameters changed (block machined, aftermarket heads, heads cut) you will absolutely have to check valve to piston clearance.

i think a stock 5.9 bottom end is capable of churning out 450, but getting there will likely mean compromises in streetability. on the one dyno test that just touched 400 they used a very similar cam to yours and an air gap but topped it with a holley 950. and headers, you'll need those. i think with a single plane and big carb, you get there no sweat but i prefer a dual plane and something more sensible in the air fuel metering device department.

you probably can get there, or nearly to that coveted 450 with a bump in the cam and breathing on the heads a bit. which, i mean they shouldn't be run OOTB anyway so what's a little more massaging while they're apart?

just keep in mind, that even though you'll get the number it's going to shift the power up higher into the RPM range at the expense of lower end and useable midrange.
 
I used to run a 223/230/110 Hughes cam in my alloy-headed 367 street car. That cam was at least a hunert times more fun than the 292/292/108 Mopar it replaced.
I ran the 223@ 11.3 Scr.
Absolute Power on the street don't mean that much. Better it is to have the right amount of power at the right time, and that will be dictated largely by having the right Second Roadgear. Get that right and even 230hp is fun.
The 223 didn't make much power, by it's 1/4 mile speed and weight, about 335hp.
IIRC it pumped ~195psi.
Great street combo
 
I used to run a 223/230/110 Hughes cam in my alloy-headed 367 street car. That cam was at least a hunert times more fun than the 292/292/108 Mopar it replaced.
I ran the 223@ 11.3 Scr.
Absolute Power on the street don't mean that much. Better it is to have the right amount of power at the right time, and that will be dictated largely by having the right Second Roadgear. Get that right and even 230hp is fun.
The 223 didn't make much power, by it's 1/4 mile speed and weight, about 335hp.
IIRC it pumped ~195psi.
Great street combo

I gotta agree for a true street driving car with pep, a cam between 220 & 228 @050 is ideal. Lower than 220 is enhanced driving and above 228 is leaving the “Drivers” range of that easy driver.

There not a big power maker but there very peppy and still easy to live with. Your overdrive, even if only just a 4spd OD is a really nice streetable package.
 
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