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precisionturbomustang

Comp 273 Installed

47 posts in this topic

I searched and searched before trying this cam and came up with hardly no info. Anyway, I gave it a try. Car seems to be ruining great so far with a base tune by Johan. Here is a quick video of the first start. Jegs exhaust with stock cats.

 

Yesterday I gutted the cats, I swear it sounds and runs like a different car with them gone. I will upload another video soon. Please ignore my filthy wharehouse and car.

 

Ptm

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Stock springs.....

I found several threads with 5.7 guys who used 6.1 springs.

 

 

Well here is some advice.  Springs are cheaper then a motor.  And that cam runs a fine line of needing a better spring. Ive seen a couple 6.1 springs break through out the years with that cam..

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Me luvs an aftermarket cam. I went with a PWR/Lunati blower cam. Got an 80 hp gain. Well worth it.

 

Don't want to be a Debbie Downer but...... those springs will be the weak link. I went with PSI springs and forged pushrods.  Pushrods not really needed but what the hell. .. you are already in the engine.... might as well drop them in. Hundred bucks for the rods is extra insurance.

 

Stevo

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You need springs. Theres no fine line. You will either float the valves or break a factory spring. Get a spring kit. And don't just get springs, you need shims and locators to get the correct spring heights.

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Can someone recommend the proper springs etc? Anyone want to loan me a spring compressor and spark plug air fitting?

 

 

Pretty crazy considering the lift is less than the stock cam.

Stock lift:

 

.571/.551

 

Comp 273

.547/.550

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PSI is recommended by just about everyone. They have the best track record on a Gen 3. Do not ever use a Comp 918. They have caused the deaths of more motors than I can count. It's not just the lift, its the aggressive ramp rates.

 

P.S......not sure where you got your info but the stock 6.1 is smaller than that.

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Depends. There is lots of correct info on LX.......more than anywhere else. But some is not. 541/547 is what I remember being correct although I have a Chrysler factory book that shows it being closer to what you posted. Not sure what they used for RR when they posted that number however the cam has a .341 lobe lift.

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Erik installed this cam (GTP Heads/PSI springs) in my 09 6 spd and it likes rpm/gears. OST tuned and power is from 4K up so a converter may work for ya. 12.1X/12.2X@115 here.     

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My info was from the lx forum, probably is wrong, lol.

Problem iis there are several different srt springs and they all have their own characteristics of pressure and coil bind. Best bet is the psi1511 installed at 1.800 and you won't have any worries. Just buy from Dave ^^ and you'll get everything you need with no guess work.

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Figured I'd add a quick update. Went 12.0@114 yesterday on 295/45 et streets. 1.71 60 foot. Broke an axle on the next pass. Going to try 09 and up axles and hubs . Cam is working pretty good. Shifting at 6500 on stock valve springs still.

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