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what type of cam for a 5.9 magnum with stock efi

Posted By: Andrewh

what type of cam for a 5.9 magnum with stock efi - 07/15/08 09:28 PM

If you had a 2000 magnum 5.9 and could reprogram the computer and just wanted a cam change, what is the most you could expect to put in and still use the other stock efi stuff?
Is that too general of a question?
Posted By: MoparJoe

Re: what type of cam for a 5.9 magnum with stock efi - 07/15/08 10:38 PM

A cam change with the stock tuning and stock keg manifold is worthless. The manifold is done at 3,500 and the PCM shuts down everything at 5k.

Get a Mopar 2 barrel M1, headers and free flowing exhaust and turn the limiter to 6k and you can pick up about 70hp at 5,000rpm, it gets better MPG and is more fun to drive, this is with the stock cam.

For a shelf grind the comp 206/210 works well, keeps the low end but pulls better after 3k and is done around 5,500.
Posted By: Andrewh

Re: what type of cam for a 5.9 magnum with stock efi - 07/16/08 01:06 AM

not using the stock computer at all.
So the keg manifold is worthless?
Thought it was good due to the long runners.

So there is no cam worth putting in with the stock intake and injectors to get more hp out of it?

I thought chrysler was putting out an efi system that required you to change the cam to the 380 hp crate motor cam to work. I understood that all it was was a cam change to get there.
Posted By: MoparJoe

Re: what type of cam for a 5.9 magnum with stock efi - 07/16/08 03:30 AM

The problem with the intake is the runners are too long and narrow and it has too much plenum volume, great for pulling a camper but bad for performance.

On my old Dakota I already had headers, PCM and a 52mm TB and picked up 80rwhp over 5k when I swapped to the M1, it only picked up 35hp at peak but didn't hit a wall at that point, it may have effected the low end but with a 2,400 stall and 3.92's I couldn't tell.

The M1 still uses all your factory parts, your injectors are fine until about 280 rwhp then you can swap to the 19# ford injectors - they actually test around 21#.

On magnums there is much more to be gained from opening up the intake and exhaust than there is changing the cam and once your at that point you might as well get better heads too.
Posted By: WO23Coronet

Re: what type of cam for a 5.9 magnum with stock efi - 07/16/08 04:16 AM

What are you guys using for PCM's? I have a 95 Ram and am wondering if any of the tuner chips are worth it?
Posted By: patrick

Re: what type of cam for a 5.9 magnum with stock efi - 07/16/08 12:48 PM

a trick if you're cheap I've seen work with good success is to cut the runners down on the beer barrel. it was designed for idle-3500ish performance, cutting ~2" off the runners doesn't seem to really affect low end, but the power band pulls a lot stronger in the 3500-5500 RPM range.

if you didn't want to touch the computer, I'd probably go no bigger than the comp XR258HR.
Posted By: Clair_Davis

Re: what type of cam for a 5.9 magnum with stock efi - 07/16/08 01:27 PM

Are there some parameters that the Painless system can adapt to, or is it going to allow full programming? I was under the impression that their system was geared towards pretty much stock engines, but I haven't really followed up with them since they first asked for guinnea pigs...

Clair
Posted By: Andrewh

Re: what type of cam for a 5.9 magnum with stock efi - 07/16/08 02:16 PM

Well, while I was there picking up the engine, they mentioned they wanted to do a stock program and a performance program.

So after I get the car to them, they are going to finish the test and tune with the stock motor.

They asked if I would upgrade the fuel system so they could drop in a cam and do a performance program for it. Now their computer is fully programable, but you need a wide band o2 sensor to do it yourself, and they charge for their software to do it.

You can buy their managment system with or without software apparently, so they wanted to offer a few choices if you didn't buy the software.

At the time I was under the impression that mopars efi system for the magnum bolted up to the stock magnum with just a cam change to make it the same as the 380 hp crate motor. Now I am not so sure.

I also found out that the old sensors for our cars will work, since the holes mopar used till at least 2000 were the same as the holes from 65, so I just need to drop factory 65 sensors in the holes. Painless didn't use any of the factory sensor locations apparently.
Posted By: Andrewh

Re: what type of cam for a 5.9 magnum with stock efi - 07/17/08 03:00 PM

btt
Posted By: Sub95

Re: what type of cam for a 5.9 magnum with stock efi - 07/17/08 06:18 PM

Just seen this. my ram is a 95 also.

Cam is a comps

Basic Operating RPM Range: 800-5,000 RPM
Intake Duration at 050 inch Lift: 205
Exhaust Duration at 050 inch Lift: 210
Duration at 050 inch Lift: 205 int./210 exh.
Advertised Intake Duration: 262
Advertised Exhaust Duration: 264
Advertised Duration: 262 int./264 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.480 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.512 in.
Valve Lift with Factory Rocker Arm Ratio: 0.480 int./0.512 exh. lift
Lobe Separation(degrees): 112

you will have to change springs.

I am using mopars aftermarket computer. and advanced the crank sensor.

Intake has been ported/cleaned up.

heads have been ported ( which hurt the low end bad under 3k ) but gave it a real good top end. I will be changing them out for a stock set just with a clean up on them.

fuel system is stock. other then a stock replacment pump.

it sounds real good with single 3" two chamber flowmaster dumbed before the axle. I tried a pair of shorty, smog legal headers on it, and they did nothing for it.

A little about the truck. its a 95 extened cab, short bed 4x4 ( auto bone stock with big tranny cooler ) on 40" tires, gears are 4.88.

I use it mostly for offraod, i do tow a 8000lb trailer with it, when i changed to the ported heads i lost 10mph through a section of road where i knew i should be able to go faster on, thats why i am going back to the stock heads to gain my low end back. But it runs great for what i do with it.
Posted By: Andrewh

Re: what type of cam for a 5.9 magnum with stock efi - 07/17/08 07:08 PM

did you have to special order, or was it an off the shelf thing.
Do you think it did much for the motor, or were all the changes you did too much to tell?
Posted By: ZIPPY

Re: what type of cam for a 5.9 magnum with stock efi - 07/17/08 07:20 PM

Quote:



I thought chrysler was putting out an efi system that required you to change the cam to the 380 hp crate motor cam to work. I understood that all it was was a cam change to get there.




It's a pretty big kit, a couple of the things included in it are an M1 single plane intake and a 1000cfm throttle body.
Posted By: Andrewh

Re: what type of cam for a 5.9 magnum with stock efi - 07/17/08 07:46 PM

what is the stock throttle body cfm?
Posted By: Sub95

Re: what type of cam for a 5.9 magnum with stock efi - 07/17/08 10:17 PM

The only thing i did was the cam springs and computer, and at the time i only had 36" tire with 3.55 gears, friends truck same as mine but a 01 and 35" tire and he got left way behind me

Comps P# 20-602-9 Grind# CRS262HR-12

CFM on stock throttle bodies are not very big at all.
Posted By: Andrewh

Re: what type of cam for a 5.9 magnum with stock efi - 07/18/08 02:48 AM

Thanks for the info will pass it along.
Posted By: patrick

Re: what type of cam for a 5.9 magnum with stock efi - 07/18/08 12:22 PM

the stock throttle bodies are 50mm blades, BUT the bores neck down to ~45cfm. if you machine them out to a straight 50mm and profile the top a bit, a stock throttle body should flow ~750 cfm. stock I'd swagger it's in the 550cfm range.
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