Bone Stock 318 Magnum dyno run.

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IQ52

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Well, we did use the Summit tubing headers also.

Finally figured how to run a fuel injected Magnum on the dyno with a stock computer. Now we can re-program it and re-test the 360 Magnum with the fuel injection and not the carburetor. So as to not ruin anything while we learned how to use the Magnum computer, we thought we'd pull the grandaughter's 1998 300,000 mile 318 out of her truck and run it first. It made a lot more corrected horsepower than I thought it should.

RPM..............TQ/HP

1900...........272/98
2000...........269/103
2100...........269/108
2200...........278/116
2300...........284/124
2400...........294/134
2500...........296/141
2600...........292/144
2700...........291/149
2800...........284/151
2900...........282/155
3000...........280/160
3100...........283/167
3200...........280/171
3300...........280/176
3400...........280/181
3500...........274/182
3600...........270/185
3700...........275/193
3800...........276/200
3900...........276/205
4000...........281/214
4100...........274/214
4200...........269/215
4300...........262/214
4400...........258/214
4500...........246/211

The old girl has held up nicely. Even with 300,000 miles on it, it still held 63 psi oil pressure @ 4500 rpm and 56 psi @ 1900 rpm at the start of the test. It will be months before this 318 is rebuilt and rerun on the dyno, but it should be fun to see how it turns out.
 
Impressive. Love watching, the working the stock F.I system in action. Subscription, indeed.
 
Even after 300K, it still has only 15+- HP less than factory rating.

What accessories are attached?

Sweeeet!
 
YY1 said:
Even after 300K, it still has only 15+- HP less than factory rating.

What accessories are attached?

Sweeeet!
Click to expand...

What, like alternator, power steering and air conditioning? On the engine dyno? I'm too lazy.

So none, it's even running an electric motor to turn the water pump.
 
We need a video of this one. Those are impressive numbers! tmm
 
That's cool - are you trying to break into the PCM coding or just looking to document changes to physical parts?
I think it is down a bit more when you consider it's not running any accessories or the water pump. Probably closer to 30hp less if it was run with a true "net" testing type accessory load, maybe another 5-10hp gained by runing the headers and not full eexhaust which is what the factory ratings include. IMO anything 15 years old and running acceptibly at 300K is worth celebrating when you consider the design intent was to last the payment period.
 
They werent all that to begin with , but not bad for 300k.


How much flow do you get out of magnum heads and how much time did it take to figure it out, how many castings you may have gone through?
 
I love these dyno tests of stock engines, especially the 440 you did. I can't wait to see how this turns out! Wish I could dyno the 360 mag I did, its still here on my stand.
 
Really interesting. Not something you see done.
 
moper said:
That's cool - are you trying to break into the PCM coding or just looking to document changes to physical parts?
I think it is down a bit more when you consider it's not running any accessories or the water pump. Probably closer to 30hp less if it was run with a true "net" testing type accessory load, maybe another 5-10hp gained by runing the headers and not full eexhaust which is what the factory ratings include. IMO anything 15 years old and running acceptibly at 300K is worth celebrating when you consider the design intent was to last the payment period.
Click to expand...

There are SCT tuners available to reprogram the PCM from 1996 and forward. The 360 is ready to be installed in the truck after we tune the PCM and retest the 360 on the dyno with the PCM.

The 318 project is up in the air, but I'm thinking it will be getting PCM tuning, cam, injectors, intake manifold and some ported Magnum cylinder heads. It still has to pull good down low as it cruises the highway at 1800 rpm.
 
Cool. I always thought the code was unbreakable and those tuners didn't do much. Admittedly it's not really my forte... I haven't had to work with them in 15 years but bcak then it was damn near impossible.
Are there certain calibration windows in which changes can be made?
 
Hebrews10:26 said:
They werent all that to begin with , but not bad for 300k.


How much flow do you get out of magnum heads and how much time did it take to figure it out, how many castings you may have gone through?
Click to expand...

We haven't gone all out on a Magnum head yet. The 360 Magnum we had on the dyno had some mildly modified Magnum heads.

Lift................Stock INT.............Ported INT

.100..................63.........................75
.200.................123.......................137
.300.................179.......................191
.400.................211.......................229
.500.................211.......................256
.600.................212.......................256

We've been able to put the J heads to 270 cfm @ .500" and 292 cfm @ .600" so I see no reason not to believe the Magmun won't go at least that much.
 
IQ52 said:
We haven't gone all out on a Magnum head yet. The 360 Magnum we had on the dyno had some mildly modified Magnum heads.

Lift................Stock INT.............Ported INT

.100..................63.........................75
.200.................123.......................137
.300.................179.......................191
.400.................211.......................229
.500.................211.......................256
.600.................212.......................256

We've been able to put the J heads to 270 cfm @ .500" and 292 cfm @ .600" so I see no reason not to believe the Magmun won't go at least that much.
Click to expand...

I'd like to think the same, being what you know.
Thing is , that pinch....its massive and makes lots o air speed, also the bowl doesnt seem near as deep, water under the spring pads....how reliable would you guess a mag head moving flow like a 290@.600 la head is?
More crack prone ?
 
Hebrews10:26 said:
I'd like to think the same, being what you know.
Thing is , that pinch....its massive and makes lots o air speed, also the bowl doesnt seem near as deep, water under the spring pads....how reliable would you guess a mag head moving flow like a 290@.600 la head is?
More crack prone ?
Click to expand...

I'm not losing any sleep over Magnum heads cracking. Every Magnum engine I have ever torn down had cracked heads, every one. I have never had to tear down a Magnum engine because the heads were cracked.
 
IQ52 said:
I'm not losing any sleep over Magnum heads cracking. Every Magnum engine I have ever torn down had cracked heads, every one. I have never had to tear down a Magnum engine because the heads were cracked.
Click to expand...

lol Thats some good luck, i had two cause misfire codes and had to pull n replace a single head and then another both. Exh seats each time and nothing/no issue leading up to that.
I know what you mean though, just press a seat when the crack isnt too bad.
J heads crack too, for me i had a set that were cracked on the outside exh flange...i couldnt believe it
 
IQ52 said:
We haven't gone all out on a Magnum head yet. The 360 Magnum we had on the dyno had some mildly modified Magnum heads.

Lift................Stock INT.............Ported INT

.100..................63.........................75
.200.................123.......................137
.300.................179.......................191
.400.................211.......................229
.500.................211.......................256
.600.................212.......................256

We've been able to put the J heads to 270 cfm @ .500" and 292 cfm @ .600" so I see no reason not to believe the Magmun won't go at least that much.
Click to expand...

So, not much to report as far as progress on the 318 rebuild, we don't get a great deal of time to work on our own stuff. But here however are the lastest results on the factory Magnum heads being prepared for the 318.

Lift...........this port stock........and after porting

.100"..............65 cfm.....................88 cfm
.200".............127.........................151
.300".............177.........................203
.400".............203.........................242
.500".............201.........................271
.550".............204.........................280

Going to be interesting when this 318 gets back in the truck.
 
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