Youtube videos dyno 318 magnum stock vs cam upgrade

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Here's youtube videos I cam across where guy's do stock ish 318 magnum stock longblock and cam with chinese airgap 650 and headers dyno 233 hp @ 4200 rpm at wheels then swap in something like the cam described below and made 255hp @ 5100 rpm at wheels and made hp at all the powerband rpm over stock cam while adding about 1000 rpm more of usable power. They didn't change the springs which could of gave more revving potential. Not Bad for 318 Magnum with that cam, probably on par with stock 340 performance and still pretty mild. like to see what a more aggressive cam would do like the 380hp create engine cam.

Grind Number:XR265HR-14
Engine Family:Chrysler 273-360 c.i. 8 Cylinder (1964-2002)
RPM Operating Range:1,200-5,400
Cam Type:Hydraulic Roller
Lifter Style:Hydraulic Roller
Camshaft Series:Xtreme Energy Computer Controlled
Camshaft Gear Attachment:1-Bolt
Usage:Street/Performance
Valve Springs Required:Yes
Camshaft Material:Austempered
California Proposition 65:WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov
Advertised Intake Duration:265
Advertised Exhaust Duration:273
Intake Duration at .050 Inch Lift:216
Exhaust Duration at .050 Inch Lift:224
Intake Valve Lift:0.506
Exhaust Valve Lift:0.506
Lobe Separation:114
Assembly Lubricant Included:No


You got fast forward through 90% of each video if you only want to see the dyno ****.

 
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318willrun said:
at the wheels that's pretty good
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I was hoping that cam would do a little better but still I've been toying with the idea for a while to down grade my 5.9l 380hp create engine with that cam and swap the M1 with a beer barrel intake and 5.9l computer I got.

Then pick up a 273 rering zero deck bore notch add the heads off the other magnum I got and use the create engine intake and cam and see what she can do :)
 
They said you have to pull the heads off to pull out the roller lifters on a Magnum engine. You do not have to. I replaced mine (95 Dakota) without doing this. It's a tight fit with the head gaskets, but can be done fairly easy. I have over 200 miles on mine with NO problems at all.
 
Interesting the got 233 RWHP when that engine is only rated 230-ish net HP from the factory.

I'm pretty sure RWHP wasn't the rating method used during those years.

If someone can prove otherwise.....
 
Your right YY1. I'm pretty sure the factory took the HP rating at the crank. 233 RWHP ain't too bad for a basically stock engine.
 
niceolddart said:
They said you have to pull the heads off to pull out the roller lifters on a Magnum engine. You do not have to. I replaced mine (95 Dakota) without doing this. It's a tight fit with the head gaskets, but can be done fairly easy. I have over 200 miles on mine with NO problems at all.
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yep, pulled the roller lifters out of my 5.9 with the heads on, no problem.
 
Correct, HP ratings from the factory are flywheel. They even tell you so. Now figure in drivetrain power looses. IDK the trans model, driveshaft, rear end model, gears or tire size.
 
niceolddart said:
Your right YY1. I'm pretty sure the factory took the HP rating at the crank. 233 RWHP ain't too bad for a basically stock engine.
Click to expand...

Do they detail the rest of the build before they start swapping cams?

I've wanted for quite a while for a true "scientific method" cam shootout.

For what ever reason's most mag cam swap articles change a bunch of other stuff at the same time even though they bill "just a cam swap".
 
niceolddart said:
They said you have to pull the heads off to pull out the roller lifters on a Magnum engine. You do not have to. I replaced mine (95 Dakota) without doing this. It's a tight fit with the head gaskets, but can be done fairly easy. I have over 200 miles on mine with NO problems at all.
Click to expand...

If you get tricky you can also pull the cam first and change the lifters by "carefull" dropping them down, then pulling them back up through the casting holes. I did this on one I tore down ---there was enough varnish that several lifters would not pull out the top
 
YY1 said:
Do they detail the rest of the build before they start swapping cams?

I've wanted for quite a while for a true "scientific method" cam shootout.

For what ever reason's most mag cam swap articles change a bunch of other stuff at the same time even though they bill "just a cam swap".
Click to expand...
I was wondering the same. The add ons are probably buried in the first video. Intake, carb and headers I bet but the cam swap was all they did so they say.
 
YY1 said:
Do they detail the rest of the build before they start swapping cams?

I've wanted for quite a while for a true "scientific method" cam shootout.

For what ever reason's most mag cam swap articles change a bunch of other stuff at the same time even though they bill "just a cam swap".
Click to expand...
Yep, Chinese Air Gap, 600 Holley, and headers. They took the stock roller out and put a HFT back in. No valve spring change.
 
I'd have liked to seen what a different carb would have done... just for kicks a 650 DP.
 
Still questioning the net vs rwhp numbers.

Not sure a carb, intake and headers would be enough to overcome the trans and accessory loss.

Those magnum exhausts flow dang near as good as most headers and the FI vs the carb might be a wash.

...and a HR cam swap would be real nice.
 
YY1 said:
Still questioning the net vs rwhp numbers.

Not sure a carb, intake and headers would be enough to overcome the trans and accessory loss.

Those magnum exhausts flow dang near as good as most headers and the FI vs the carb might be a wash.

...and a HR cam swap would be real nice.
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I am surprised they didn't just swap the cam to another hydraulic roller. Reuse the stock lifters. No break in issues.
 
They used a used cam so there were no brake in issues even though one of the guys coated the cam. You can hear what he said in the video about it.
 
rumblefish360 said:
They used a used cam so there were no brake in issues even though one of the guys coated the cam. You can hear what he said in the video about it.
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I laughed, Dad said something like "if it goes flat we will just have to fix it"
 
Another plus for a roller- zero brake in issues, and can re-use the lifters.
 
YY1 said:
Another plus for a roller- zero brake in issues, and can re-use the lifters.
Click to expand...
especially with cam failures going crazy with FT. So many competent builders are loosing flat tappets anymore it's stupid crazy. I have to believe it's a Quality thing. I'm pushing more towards rollers in my future with small blocks. Pretty easy to get a roller motor - Magnums and later LA's. Just makes sense.
 
toolmanmike said:
Yep, Chinese Air Gap, 600 Holley, and headers. They took the stock roller out and put a HFT back in. No valve spring change.
Click to expand...

They were gonna put a flat tappet back in cause he already owned it but they couldn't get the lifters out so they used a roller cam like in the original post.
 
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YY1 said:
Interesting the got 233 RWHP when that engine is only rated 230-ish net HP from the factory.

I'm pretty sure RWHP wasn't the rating method used during those years.

If someone can prove otherwise.....
Click to expand...

I could see headers, free flowing duals, 4bbl and airgap intake, better tune, probably accessories on the dart take less hp make up for the probably 50-60 hp drivetrain loss.
 
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