more out of 5.9l 360 magnum

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moparmike98

moparmike98

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I have a 5.9l mopar 360 magnum the 405hp version. I would like to know some upgrades I could do to increase overall performance without breaking the bank too bad.
 
Have your heads , given a good valve job, and a pocket port..
 
Are the heads mopars version of edelbrocks?

bomber has a good approach.
 
Nitrous is fairly in expensive if you are interested in that route. Just make sure the tune is right!
 
I'd like to know ecatly what aluminum head is on there.

But Abomber has a excellent idea. I'm not so sure IF the engine is a true 10-1 and milling them more pushes octane issues. I myself run a 11-1 Edelbrock headed 360. But not with such a short duration cam as the MP create engine has. I can use 93 octane. The cams used in the past have always been 248* hyd. & solid or bigger in duration.

If you take the heads off for some work, measure where the piston sits in the cylinder at TDC.

If your looking for more street friendly manors, AKA torque, a RPM intake for that engine is an excellent choice. it should give up no HP on the big end at this stage of the engines build.
 
You have all the parts. If you pull the heads, you may as well dis assemble the rest. See where the deck clearance is. If the block can be decked to zero, do it. As Bomby boy suggest, attention to the heads is a good idea. I would fully port them though. IMO, if you're gonna do it, DO IT.

Nitrous is ok. It does work. You need to understand though, the engine needs to be built for nitrous for best results. Just throwing nitrous on an already built engine often times does not give optimum performance. Just food for thought.
 
Tearing it down costs money, but blue printing the engine gives long life and higher power numbers. Have it zero decked, bearing tolerances checked, engine rotating assembly balance. Have the heads ported and gasket matched will equate to bigger flow numbers. Check quench and cam timing. But it already seems like a strong engine and you should look at the goals you want the car to set for you. Don't overlook the transmission, torque converter, traction device, tires.
 
after you go through the heads and measure your clearances...what about doing a simple 1.7 rocker swap. Something like harland sharp makes a bolt on kit that once you make sure your push rods are the correct length is just a bolt on piece.
 
blk00rt said:
after you go through the heads and measure your clearances...what about doing a simple 1.7 rocker swap. Something like harland sharp makes a bolt on kit that once you make sure your push rods are the correct length is just a bolt on piece.
Click to expand...

Bigger rockers is a great idea for him. To put into perspective, I have a 360 mag with .534 lift and because of lifter geometry I have .500 dynamic valve lift. The cam in his engine is mild in terms of lift and 1.7 rockers would be a quick fix , not too expensive , more accurate and mostly cheaper than a new cam. Figure a new cam is 350 plus a 100 oil pump drive. Although you may need new pushrods in both scenarios . Do you like the power band of that cam? Do your heads use factory rockers?
 
What else is done to the engine and car? What car is it? C'mon, you're not going to get any real advise until we know what you've already got. Tell us everything you know about the car as it sits, and THEN we can help point you in the right direction. Lots of smart guys on this site. Are you wanting a good cruiser that may see the track every once in a while, or do you plan on doing a little bracket racing? Are you concerned with fuel mileage? Do you make long trips in the car or do you tend to just cruise around town?
 
I have a 72 duster with a 4 speed. Engine is not modified to my knowledge front end was redone manual steering and brakes. I believe new tranny was put in before I bought it. And they had a demon 850 carb on it. 8 3/4 rear end.
I'm looking for a powerful street car that makes a stop at the track every once in a while. At the moment I am just planning on what I could do.
 
You need to know what gears are in the rear. Is it a sure grip? What converter is in the trans? Maybe get someone who knows how to dial in the engine you have. A lot can be left on the table because of poor tuning. Maximize what you have before you start tearing things apart.
 
Thanks for the tips I will definitely put what you said to use but at the moment I am just seeing what I could do later on.
 
Does it have the Mopar M1 single plane intake on it? If so, ditch it for an Edelbrock Airgap. The M1 kills the midrange power while the Edelbrock will boost the midrange and make as much (or possibly more) power at high rpms. I personally experienced this with my old 360 magnum.

What carb is on it now? Still the 850 Demon? If so, it's far too big of a carb and again you're losing midrange and throttle response. Demon carbs are wet flowed so their advertised numbers are a little deceiving if you're not used to it. That carb is WAY bigger than it's Holley or Quick Fuel counterparts. IMO a Holley or Quick Fuel 750 would be just about perfect, but the Proform Street series 750 (I hear) is an excellent low budget carb.

Does it have headers? What type of exhaust does it have? Tube size? H-pipe or x-pipe? What mufflers?

To answer your question about the spacer, it's hard to tell since I don't know exactly why intake and carb you have yet. However, my personal experience with my old 360 magnum was that it like a 1" open spacer on top of the Edelbrock Airgap intake, but liked no spacer (open or 4 hole) when I ran the M1 single plane.

In case you're wondering, the reason I'm focusing on low-midrange is because generally it will make the car more fun to drive. You'll experience the benefits more often since that will be the rpm range you drive in most, instead of having to rev the crap outta your motor to ( maybe) feel a few for hp. Besides, that engine is pretty maxed out as it is with the heads that are on it (without work, of course), and your money is better spent on optimizing what you've got instead of trying to improve on a combo that may or not already be optimized.
 
I was looking to get a holley 750 but didn't know which one. How did the edelbrock fit? I'm looking at getting some tti 1-7/8 headers possibly. Unsure on exhaust size and mufflers they look almost glass pack like, just bigger than pipe and somewhat long. True dual exhaust no h or X I believe. Is it the edelbrock performer rpm intake
 
Yeah it's the Performer RPM, but it's generally just called the airgap, p#7577.
http://www.summitracing.com/parts/edl-7577

Fitment wise, it bolts onto the motor just like the other. The only real differences would be things like thermostat housing, coolant fitting locations, etc, but you can just compare a picture of the airgap and the one you have to see the differences. There should be no major differences unless the intake you have has the larger (older style) thermostat housing, but I'm thinking you have the smaller (magnum size) housing.

The best intake gasket kit I've seen (and have used several times on mine and other friends magnums) is the kit from Rock Auto. It comes with a few parts you don't need but for the price it's a good deal IMO.
http://www.rockauto.com/catalog/moreinfo.php?pk=2194496&cc=1361810

Here's a list of carbs I'd consider acceptable for your application. I hope this works, it's a refined list of carbs.
http://www.summitracing.com/search/...e=100&SortBy=DisplayPrice&SortOrder=Ascending

When it comes to the headers, 1 3/4" primaries will be more than plenty. No need for the added headache and expense of the 1 7/8". TTI and Dougs seem to be the ones guys prefer but I'd ask around. When it comes that there are guys that know more about the specific of installing headers in an Abody than me.

Exhaust wise, a basic dual 2.5" exhaust with either and H or X pipe and your choice of muffler would be fine.
 
Dougs or tti headers are all you'd need. I like Dougs because they work, fit well and are ~250-300 less expensive than tti. The 1 3/4 step headers just don't provide enough benefit for the extra expense.
 
crackedback said:
Dougs or tti headers are all you'd need. I like Dougs because they work, fit well and are ~250-300 less expensive than tti. The 1 3/4 step headers just don't provide enough benefit for the extra expense.
Click to expand...

True. But being 1 of 2 headers designed to fit nice and they work very well, it just kind of really stinks that they were not designed this way back in the day so that perhaps, perhaps they cod be an inexpensive design header to purchase today.

The tti affords a higher ceiling mevel of power while working well on lower powered engines.
I'd like to see a dyno shoot out between them. Interesting thought.....
 
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