6.2L performance mods...again.
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Just curious to see if anyone has had any luck with simple mods to stock 6.2 MPI engines. The most recent posts I have read are over a year old and express various opinions of cost vs. gain. The K&N issue seems to concern application...have they (K&N) come up with any arrestors that are made for the 6.2? Any other advice/info will be appreciated!
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We've added Stainless Marine exhaust to a stock engine and picked up 1, maybe 2 MPH and a good midrange improvement. The MPI is the same as a 350 Mag, so a 350 Mag flame arrestor will work. You could swap in a set of 1.6 rocker arms for another 5-10 HP. You can't do anything with the ECU programming if you have the Motorola ECU. You could add an adjustable fuel pressure regulator to richen it up just a tad after the mods. Beyond that you will have to go internal to the engine.
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Thanks for the reply. I will visit your website to check pricing and availability. How would I know what ECU is installed on the engines? Also, will the addition of any of these mods effect the warranty?
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Gferdon, I had some 6.2's that I did a few things to. I Installed the 1.6 ratio rockers, Large oil pan, Change the ECU to a Mefi3 that we could re-map, Aluim. Heads, ARP Stud Kit on Mains, & Whipple Superchargers.
I assume that you are not looking to Add a Whipple but that is by far the best way to make HP with that motor.
The Higher ratio Rockers did work well but I had a problem braking Rocker Studs. I went to the Longer ARP's and I "think" that would have fixed it. (I forgot to tighten one of the Polly Locks and a rocker came loss resulting in a piston thru the side of my block, I was running at 15lbs of boost so I didn't have much room for error but thats another story) Anyway I still have two sets of Comp Red's in the 1.6 ratio if you are interested. Just make sure to have someone that knows what they are doing install them.
If you can get a MEFI3 then I would suggest changing heads and cam. That motor can take a ton of abuse.
Pyle
I assume that you are not looking to Add a Whipple but that is by far the best way to make HP with that motor.
The Higher ratio Rockers did work well but I had a problem braking Rocker Studs. I went to the Longer ARP's and I "think" that would have fixed it. (I forgot to tighten one of the Polly Locks and a rocker came loss resulting in a piston thru the side of my block, I was running at 15lbs of boost so I didn't have much room for error but thats another story) Anyway I still have two sets of Comp Red's in the 1.6 ratio if you are interested. Just make sure to have someone that knows what they are doing install them.
If you can get a MEFI3 then I would suggest changing heads and cam. That motor can take a ton of abuse.
Pyle
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The Motorola ECU is a silver unit whereas the MEFI 3 is solid black. The exhaust shouldn't void the warranty. Changing rocker arms or fuel pressure most certainly would. I don't have a lot of info posted on my web site. It's still in progress. Give me a call if you'd like to talk.
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Cat & Mice, what aluminum heads did you use? Dustin was trying to talk me into the Edelbrock E-tec heads with his supercharger. What kind of HP are you getting? Naturally aspirated I believe the Vortec heads with porting and larger valves are as good as anything out there up to .525 lift. Aluminum is definitley the way to go with a supercharger.
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Since the boat is only two weeks old, I am a bit reluctant to do anything that will void the warranty so the rockers are out for now...thanks anyway C&M. The exhaust and K&N sound like a very reasonable investment. I was unable to reach the TFM website only saw the testimonials from satisfied customers. I will give you a call to discuss the exhaust system. I went to the K&N website and found what they list as a small block, late model MPI with serpentine belt system flame arrestor kit. It consists of two units, an adapter and the arrestor itself...does that sound right?? I will check the ECU later today and see what I have. With the addition of the exhaust and intake, would you still increase the fuel pressure/volume?
Good weekend to all.
Good weekend to all.
Last edited by gferdon; 09-13-2003 at 01:33 AM.
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bobl, I don't think Dustin had a intake for the Vortec when I did mine, We used the Dart's.
I would agree that if you can use the Vortec style that would be great.
We Got just under 600hp out of my old setup. The new 406ci are making over 800hp. I still have both of the blocks from the old motors, one is still in great shape with pan to intake.
Pyle
I would agree that if you can use the Vortec style that would be great.
We Got just under 600hp out of my old setup. The new 406ci are making over 800hp. I still have both of the blocks from the old motors, one is still in great shape with pan to intake.
Pyle