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Discussion Starter · #1 · (Edited)
has anyone put in those new comp cams in thier 5.7? I have been thinking about swapping out my cams want to know if anyone has done it yet. I read an article in Hot Rod and it seems pretty impressive!! 481hp!!!
 

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Mrs300c said:
has anyone put in those new comp cams in thier 5.7? I have been thinking about swapping out my cams want to know if anyone has done it yet. I read an article in Hot Rod and it seems pretty impressive!! 481hp!!!
481 .. WHAT? Are you kidding? Do you have a link to that article? I think I just solved all my little mod problems (and warranty paperwork frustrations too, lol)
 

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Probably at the flywheel, not RWHP. 15% to 20% loss to the rear wheels
 

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I have this issue of Hoy Rod, you also have to note that they ran it with a standalone engine management system, since the modified stock ECU would not let them rev high enough. Amazing numbers nonetheless.

Scott
 

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Before all get excited

Not yet read it.

Was this a truck Hemi engine without MDS or a LX 5.7 with MDS?

A "lumpy" cam is the reason the 6.1 cannot have MDS

Zilla
 

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Mrs300c said:
has anyone put in those new comp cams in thier 5.7? I have been thinking about swapping out my cams want to know if anyone has done it yet. I read an article in Hot Rod and it seems pretty impressive!! 481hp!!!

Swapping out your cams? do you have one of the SOHC 5.7's? Cuz mine only has one camshaft..... :wave:
 

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goddardzilla said:
Not yet read it.

Was this a truck Hemi engine without MDS or a LX 5.7 with MDS?

A "lumpy" cam is the reason the 6.1 cannot have MDS

Zilla

It was Hot Rod but maybe Car Craft did one as well. My brother has the Hot Rod issue and they used a Mopar 5.7 hemi crate motor (no MDS) if I remember correctly; they DID use a Comp cam but they did a lot of other stuff too..... port matched the intake and I think did some headwork as well. I don't have the magazine but they did get some pretty crazy horsepower (at the flywheel) out of it. They even tried an intake from a 6.1 but switched back because it actually detracted from performance. The ports on the intake manifold were SO much bigger than the intake ports in the 5.7 heads that there was no benefit to using the 6.1 intake.
 

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goddardzilla said:
A "lumpy" cam is the reason the 6.1 cannot have MDS

Zilla
where did that info come from?
Do you have the lift numbers for the 5.7 and the 6.1?

In the Hot Rod article all the numbers, base line (360HP), headers (400HP), and Cam (480HP) where achieved with out the catalytic converters and emissions tuning.
It would be interesting to see the difference in A/F ratio at WOT between the production Hemi and the crate version.
 

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So you want me to do your homework?

maneval69 said:
where did that info come from?
Do you have the lift numbers for the 5.7 and the 6.1?
Quoting from Car & Driver Feb 2005:

"Cylinder deactivation, standard on the 5.7, was left off the 6.1 because it didn't work with the lumpy cam profiles."

also see:

http://www.300cforums.com/forums/srt-8-general-discussion/10743-6-1l-cam-specs.html?highlight=MDS

and

http://www.compcams.com/Information...mshaftFlyer.pdf


say thankyou Zilla :wave:
 

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Hi,

It was the October issue of Hot Rod. Thee was no head work done to the motor. They adapted a Ford PCM to the motor because they could not figure out a way to make the engine rev over 5700 RPM with the Mopar PCM. This configuration probably would not be streetable.The engine was run on the dyno, through headers and probably without accessories. It is clearly flywheel HP. Nonetheless, it is a very impressive number. Once someone figures out how to hack the PCM, we should see some significant HP gains from the 5.7. Perhaps the aftermarket CAI's and exhaust systems will finally produce the gains claimed by the manufacturers after all.
In the August issue of Hot Rod, they did dyno runs on the stock crate motor. It produced 376 flywheel Hp at 5700 rpm. They swapped the stock exhaust manifolds for TTI 1 3/4" and produced 393 HP at 5700 rpm.
By the way, they also ran the stock motor with headers and the Ford PCM, prior to adding the Comp Cam. It produced 401 HP at 6000 rpm.


Phil
 

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IGOTTASRT8 said:
I read the article, basically it should be ignored until someone figures out how to tune our cars.
Ignorance is bliss
 

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Big HP just around the corner...

The point I have taken away from this article and the earlier HOTROD articles tearing into the new 5.7 is that our HEMI has one of the best damn inductions systems ever put onto a production vehicle. The factory heads flow enough air for over 550HP without touching them. The factory heads, plastic intake and stock throttle body, stock injectors, picked up over 80 hp with a cam change and was proven capable of revving to over 7K rpms (7200 I believe the article said) without changing the valvesprings..incredible design!!!

While we have many issues to overcome and work around to include emissions, drivability, computer control etc etc, these engines will be putting out serious HP by the end of next year. If my 4000lb barge can knock out 13.80's in box stock form I have no doubt my 300C will be hitting 12's by this time next year if the programmable tuners make it out early 06 (as talked about in other threads). Does anyone know have an extra 80 hp laying around?

To get back to the original question: I have yet to hear any 300C's run any of these cams with success. I too been looking for some data but only read about several Dodge RAMs having drivability issues upon initial install....haven't seen any documented HP/performance gains published yet.

Chris
 

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Discussion Starter · #18 ·
I think my Husband is going going to do the cams reguardless. He was talking with Comp cams yesterday and they told him we will deffinitly see about 50-55hp with cams only, but the real power is going to be when somone creates a new program for the computer. He says this motor is a monster waiting to be unleashed. And forget about all that MDS stuff. If your driving in MDS mode all day you should have bought a hybrid. I'm just tring to keep up with my Husbands SRT-10...
 

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Mrs300c said:
I think my Husband is going going to do the cams reguardless. He was talking with Comp cams yesterday and they told him we will deffinitly see about 50-55hp with cams only, but the real power is going to be when somone creates a new program for the computer. He says this motor is a monster waiting to be unleashed. And forget about all that MDS stuff. If your driving in MDS mode all day you should have bought a hybrid. I'm just tring to keep up with my Husbands SRT-10...

I've used COMP cams in a few Chevy's I've built including a big block for my boat; the product is first rate and the tech guys know their stuff from my experience.

I'd still like to see that Hemi that you are changing the "cams" in though; cuz all the ones I've seen only have a single camshaft! :wave:
 

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For 5.7L Hemi owners with MDS, you will not be able to change out cams or do head work beyond just porting/polishing. As Zilla mentioned, a bumpy cam is currently a no go for the MDS and you cannot change out valve springs and change the pressure on the lifters. You will have to wait until somebody can eliminate the MDS from your PCM or find out how adapt the SRT8 PCM into your vehicles. The CompCams require a stouter valve spring, so your husband is defiately in need of a chill pill.

I good mod for MDS Hemi's is going to be ported/polished heads. There is a vendor that is providing items to the Dodge truck crowd and stock head is restrictive. Reusing your valvetrain in the ported/polished head will allow the MDS to function fine and probably give the 5.7L Hemi motor a very healthy HP and TQ bump.

Todd
 
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