What carb and intake for 5.9 Magnum?

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Idaho

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Here's the basic recipe I'm considering for a 5.9 I just brought home.

http://www.hotrod.com/techarticles/engine/hrdp_0804_small_block_mopar_engine/viewall.html

LA timing case and accessories. LA oil pan.
M1 intake w Speed Demon 750 (For the Demon Clone!)
Mopar performance electronic ign. (or 74 Dart Sport factory ign)
Edelbrock RPM heads (9:1).
Stock lifters/retainers.
Comp 1.6:1 roller rockers.
Comp Magnum push rods.
Hooker 1 3/4 headers.

There may be some adjustments of course. Considering other heads used by members here for 5.9 builds. Maybe the Air Gap intake. I'm asking now just so I can be on the lookout for items that come up for sale.

Do I need to be more systematic, getting the cam nailed down first?

There's an edelbrock 750 right now but not sure...
It should be easy to tune.

Tranny will be a 4 speed.
 
There is a dead link in your post.

There is one problem to different head choices for a Magnum block, "LA" heads can not be used unless you drill an oil passage through the block or set up oil through push rods to work right, IIRC.

Cam choices are like socks in my draw, constantly changed out, for fun of course. But knowing what your going to install first is a plus.

CARB CHOICE being 750 cfm is a good all around choice for a mild to somewhat decently wild 360. Carter or Edelbrock, the choice is yours. Though, if the cam gets a bit beyond 236* of duration (At 050) I like the Holley a bit batter. And a good decent unit, not just a simple replacement unit.
 
If you go to Comp cams website you can sign up for cam quest and see hp vs torque curves of different cams.

I took my 94 360 mag to the machine shop a couple of weeks ago.
Cylinder bores were excellent with lots of cross-hatch still showing.
The rod bearings were a different story the upper side of the bearings were starting to show brass. Ended up turning the crank .010".
I put standard kb 107's in mine to up the compression, and the pistons weight difference required balancing of the recopricating assy.

To run a 4-speed you will need a flywheel for magnum balance, they run a little over $300.00

http://www.brewersperformance.com/products.asp?cat=46
 
Thanks. The PM info is really helpful too. I will likely go with the RHS heads and custom cam grind from Bullet.

Here's some of what I've dug up on carb selection.

Normally a mild converter, weak rearend gears, and/or a heavy vehicle will call for a smaller carb to retain decent low-end performance. But we know the smaller carb restricts power upstairs. One possible solution: Run the larger carb, but with vacuum (instead of mechanical) secondaries. Vacuum secondaries won’t open until the engine needs the extra airflow. Assuming the vacuum secondaries are properly tuned with the appropriate-tension spring, the engine won’t bog even if you punch the throttle wide-open at low speed. But when there’s sufficient primary airflow to allow the diaphragm to open the secondaries, the engine is ready to accept the extra capacity. Grant says vacuum-secondary carbs work particularly well if running under 3.55:1 gears, the car weighs over 3,500 pounds, or if you have 8.5:1 or less compression.

For just about any other combo, Grant recommends staying with the twin-squirter, mechanical-secondary carb. “If the engine withstands a mechanically actuated secondary without bogging, the rpm will rise quicker and performance will be better than with a vacuum secondary,” says Grant. Note that twin-squirter carbs are much more finicky about proper sizing than the more forgiving vacuum-secondary models, which is why there are more different twin-squirter sizes available in comparison to vacuum-secondary cfm ratings.

Read more: http://www.carcraft.com/techarticles/selecting_right_carb/index.html#ixzz1nWD5BVmO

The Thunder Series air valve allows the secondary actuation rate to be adjusted in seconds, without the swapping of parts, for easy and quick tuning of the secondary action. We've had lengthy street time with the AVS in a hot small-block application, and the system really works. The Thunder Series AVS can be had in 650-and 800-cfm flow capacities, and shares tuning components with the Performer Series carbs.

Read more: http://www.popularhotrodding.com/tech/0503phr_carburetor_tech_how_to/index.html#ixzz1nWFQd8IW

http://www.holley.com/applications/CarburetorSelector/CarbSelection.asp

When it comes to mechanical vs vacuum secondaries, Grant's advice would be mechanical for my plans, but the Holley carb selector advises vacuum.

Edelbrock has lower prices. The Thunder series looks interesting and apparently is fuel efficient. There seem to be more Holleys available used. I think I'll stay around 650 cfm for best low rpm throttle response.
 
OH! You don't have a carb. I was going on that list of things above as things you already have. IMO, I agree and also think you'll like the 650 AVS. Are you going to also use the same cam?
 
I haven't put a lot of thought into it but am hoping to benefit from the experience of others here, for example JoeDust451 who is running mid 12s in a factory weight car (hope you don't mind this Joe). He's using less lift than the magazine recipe allowing him to keep the factory pushrods/lifters/rockers. I'm not sure but suspect it might also make better low rpm power which I prefer.

Thanks guys/gals, the combo is this.

95 magnum, stock short block
RHS heads, re-ground stock cam from bullet (.477/.477, .218/.218 @50, 112)
Crosswind RPM, summit headers, 750vs holley
904, 2800 PTC 11", 3.73, 255/60/15 DR
MSD/Mallory

http://www.forabodiesonly.com/mopar/showthread.php?t=97354

I know LXguy has his 5.9 Magnum running in the 11s but has had some valvetrain issues and suggests a lower lift.

http://www.forabodiesonly.com/mopar/showthread.php?t=106857

So far I haven't seen anyone with a 4 speed and a 5.9 Magnum so I can't outright steal their cam recipe. :) I guess I'll talk to one of the cam grinders.
 
Idaho,that cam will be a terror in the midrange.I would go with it.
 
With a 4 speed? I'm not up on this but had the impression the recommended formula would be somewhat different.
 
Its the recovery time from peak h.p. to peak torque on the shift recovery point.That way,when you shift,the engine is at peak torque with the gear change.Known as the Lingenfelter method.Not the absolutely quickest E.T.s,gets you 90%,while being streetable.This definitely applies to Hyd rollers,and hi velocity heads.That would work optimum with a 3.55/3.73,Idaho.
 
I like that hot rod article too. It was pretty inspiring.

I am using the Iron Ram heads from Hughes, and they are performing very well for me. Supposedly they flow better than the Edelbrock and have a true 58cc chamber. They were very inexpensive and make good power. If I had it to do over again, I would have gotten the 2.02 castings and had the spring seats machined for taller springs. I ran the skinny gaskets to help with compression. I am running the stock untouched shortblock and my pistons are .050 in the hole.

The other thing I like about the Iron Ram is that you can get them with the LA intake bolt pattern. I recommend the LA style Air Gap intake very highly. I doubt I am giving anything up to the Victor/M1.

I ordered a custom cam from Comp, using their XE lobes. It is smaller than the one in the article, but only slightly. 224/230 .536/.544 110 lobe sep. Cam is very streetable (with gearing) and pulls hard to the limit of the of the original Hughes 1110 valve springs - about 6200. I usually do the cam last. As you said if I had it to do over, I'd go with less lift.

I am running the stock rocker setup. It works, but if you can find rollers I am sure that would be better.

I am running 1-5/8 coated hookers. I am sure the 1-3/4 would be advantageous, I just wanted something I could easily adapt to the 2.5 TTi X-pipe I already had.

I am currently running a 750 quickfuel double pumper (with a stick especially, a double pumper is a good choice), but the car did run some 11.90s with a 670 street avenger holley (Holley street avenger carb is an excellent "plug and play" choice). No matter what you run, I highly recommend a wideband to help with the tuning.

My car is an auto, so I'm no help there, but it puts around 330 to the tires through a 904 with a 3000-ish torque converter. By the time you do the conversions to engine hp, it stacks up pretty well against the engine in that article, and the car is much quicker than I expected.

FWIW, my Dart is basically full weight, still have the bench seat and all that. It runs right about 3400 pounds. My shortblock is in "good" shape in that it doesn't smoke or put metal in the oil, but I get about 30-40% leakdown on all cylinders (cold).

Good luck! I love my Magnum.

Steve
 
Iam running a 96 magnum basicly copied the 380hp crate engine but with a lousy 8:7-1 comp i beleive that is the factory comp? Its in a 67 dodge a-100 3600stall 727 it has ran best of 12.72 if i remember correctly at 108mph in spokane wa. dynoed 280 at the wheels
 
Thank-you LXguy for chiming in. Your threads have inspired me and I'm sure others.

Not sure what "wideband" refers to. I read up on the 670 Street Avenger - looks like another good choice with reasonable price.

Quite a difference in lift between yours and JoeDirt451. I'm not sure yet but lean to the lower lift for less valvetrain stress and good low rpm torque. Then again I'd like a lopey idle - such a pleasant sound. My understanding of cam choice is fairly superficial.

I guess I should have titled the thread carb, intake AND cam...

So I had to look up the Lingenfelter method. Didn't find much detail on his cam methodology but what a tragic story. Talented guy who's passion for racing cost him and his family his life in his prime. It should be a cautionary tale.
 
Wideband is a wideband 02 sensor. Greatest thing since sliced bread for carb tuning.

Lift doesn't really have anything to do with idle or torque. Chop is in the duration and the lobe separation (pretty much). Torque is in the overlap (pretty much).

Also, you can't really compare duration numbers between hydraulic roller and hydraulic (not that you are doing that). A roller can remains streetable/easy on parts at a much higher duration than non-roller.
 
Not that much saving in a re-grind plus snout vs new cam it would seem. I imagine a re-grind causes some limitations. Someone wrote that you get no lopey idle with a 5.9 re-grind so I presume duration and/or separation are limited.

Certainly both engines perform well. But if I can get a nice idle note an extra c note I'd go for it (feeble poetry) :)


440dart123
Iam running a 96 magnum basicly copied the 380hp crate engine but with a lousy 8:7-1 comp i beleive that is the factory comp? Its in a 67 dodge a-100 3600stall 727 it has ran best of 12.72 if i remember correctly at 108mph in spokane wa. dynoed 280 at the wheels

My Mopar Engines book lists it at 9.1:1. Hope that brightens your day.
12.7 doesn't sound that bad to me!
Long drive to Spokane. I look forward to trying out the track there - some day....
 
Just some screen shots from the Comp cams site. Very interesting and surprising to play with the parameters.
The "best perf" version is somewhat like Joe's, and the "mutha" is more like LX guy (I think).
I'll spend time educating myself before I choose but for the street and tire smokin I suspect I may like the "best perf" profile with the low rpm torque.

Edit: sorry those are so small, kinda useless... not sure why
 

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I looked over the Comp catalog pretty thoroughly when putting my combo together, and knew custom would be the way to go. Lots of the Comp catalog stuff is for trucks/EFI.

I especially recommend a custom if you're not super familiar with cam specs. There are lots of vendors who do a good job with it, and have a much better chance of getting you a good fit for what you want to do, than picking a "one size fits all" cam from a catalog with the incomplete specs the cam companies provide.

The lift on my cam wouldn't really be a problem if I had been better informed about the limitations of the EQ/Iron RAM head before ordering. I could have just had the heads machined for bigger/better springs from the get go.

As it is, the 1110 springs from Hughes handle it OK, and I certainly don't have any piston/valve clearance issues. Sooner or later I'll have the heads off, get them machined and put some beehives on it.
 
I'm just trying to educate myself. Adjusting parameters on the cam program is informative and fascinating. It also confuses me in some ways and I thought it would be interesting to use the screen shots to learn more from the guys here. I don't really expect to learn enough to make a good choice independently but will take advice from members here and whoever I buy from. That said I want to use the process to learn.

At this point I understand that cam choice is hugely important, that it largely determines the "personality" and "functionality" of the engine, and that it is a complicated and evolving art/science. I intend to take some time with the decision.

I greatly appreciate the input from the members here.

Hopefully I won't start any nasty fights :violent1: :dontknow: :)
 
Hey everyone, I'm new here. Own a 74 Duster with a small LA 360, built 727.

9.8 Comp
Purple shaft .455 lift
stock heads w/2.02 intake
Demon 750 Speed Demon (Vac. Sec.)
dual plane airgap intake

Very torqie engine to say the least. It'll almost lift the front wheels with a 2.71 open diff in the rear and stock converter (scares my girlfriend every time :D). Still working on the drivetrain... Cam may sound small, but it works very well for a mild street car. Gets 16 mpg, too. :) Haven't been to a strip yet because of the /6 drivetrain, so I can't post any numbers yet. Good luck with your build! :)
 
Welcome to the forum.
Introduce yourself in the welcome wagon and tell us more about your ride.
Everyone likes pics.
Lots of friendly helpful folks here.
 
Maybe I'm just foolin myself but when it comes to carbs, what I've learned so far suggests I could be quite satisfied with different ones from Holley, Edelbrock, or a Demon. Likely could even rehab the old thermoquad I have. Lack of parts for it likely makes it a bad choice. Perhaps the comp cams Dyno program is misleading but it does not seem to make a big difference.

Regarding intakes, I know the air gap is great and the M1 is a good choice.

I'm wondering what others are worth considering. I don't want to compromise on torque and low/mid rpm power but a giving up a little at 5000 rpm plus would not be a big deal. I see intakes coming up for sale but don't know enough to consider them.
 
It will be very interesting to see how our two builds compare. I'll be following your thread. Of course you're way ahead and my progress will be slow.

http://www.popularhotrodding.com/te...gap_performer_intake_manifold_tech/index.html

This article reads like an ad for Edlebrock which it likely is, but its the best I could find providing some hard data for intake performance. It's fairly informative about intake design. It did not however, allow me to determine whether the plain performer, the performer rpm, or an air gap version would be preferred. I'll have to research some more.

The Weiand stealth seems very comparable but I have found no solid comparison data.

It would seem that your M1 (single plane right?) may produce a little better high rpm power and give up a little torque at lower rpm.
 
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