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Need help by selecting of original camshafts

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Hello everybody,

I´m in progress of searching some parts together for my engine overhaul of the 6G72 3.0 V6 24 valve naturally aspirated Mitsubishi engine. I got a AEM Infinity EMS where it should get tuned on.

So know I have alot of camshafts laying around of different 6G7x engines which I could combine together, but I´m hard confused for which aspects I should look.

So these are the engine codes with there specifications:

6G72 3.0 V6 24V DOHC

6G72TT 3.0 V6 24V DOHC Twin Turbo

6G73 2.5 V6 24V DOHC

6G74 3.5 V6 24V DOHC

The only thinks I know about the cams are the degress of opening and closing, the rest is calculated by this website: http://www.wallaceracing.com/camcalc.php

6G72 Intake camshaft & 6G72 Exhaust camshaft

Intake Opens BTDC 16,5

Intake Closes ABDC 55,5

Exhaust Opens BBDC 48,5

Exhaust Closes ATDC 15,5

Intake Duration is 251.00 degrees.

Exhaust Duration is 243.00 degrees.

Installed Intake Centerline is 109.50 degrees ATDC.

Installed Exhaust Centerline is 106.50 degrees BTDC.

LSA is 108.0 degrees

Overlap is 31.00 degrees.

6G73 Intake camshaft & 6G72 Exhaust camshaft

Intake Opens BTDC 14

Intake Closes ABDC 58

Exhaust Opens BBDC 48,5

Exhaust Closes ATDC 15,5

Intake Duration is 252.00 degrees.

Exhaust Duration is 243.00 degrees.

Installed Intake Centerline is 112.00 degrees ATDC.

Installed Exhaust Centerline is 106.50 degrees BTDC.

LSA is 109.3 degrees

Overlap is 29.00 degrees.

6G73 Intake camshaft & 6G72TT Exhaust camshaft

Intake Opens BTDC 14

Intake Closes ABDC 58

Exhaust Opens BBDC 50,5

Exhaust Closes ATDC 17,5

Intake Duration is 252.00 degrees.

Exhaust Duration is 247.00 degrees.

Installed Intake Centerline is 112.00 degrees ATDC.

Installed Exhaust Centerline is 106.50 degrees BTDC.

LSA is 109.3 degrees

Overlap is 31.00 degrees.

6G72 Intake camshaft & 6G72TT Exhaust camshaft

Intake Opens BTDC 16,5

Intake Closes ABDC 55,5

Exhaust Opens BBDC 50,5

Exhaust Closes ATDC 17,5

Intake Duration is 251.00 degrees.

Exhaust Duration is 247.00 degrees.

Installed Intake Centerline is 109.50 degrees ATDC.

Installed Exhaust Centerline is 106.50 degrees BTDC.

LSA is 108.0 degrees

Overlap is 33.00 degrees.

6G73 Intake camshaft & 6G73 Exhaust camshaft

Intake Opens BTDC 14

Intake Closes ABDC 58

Exhaust Opens BBDC 48,5

Exhaust Closes ATDC 15,5

Intake Duration is 252.00 degrees.

Exhaust Duration is 243.00 degrees.

Installed Intake Centerline is 112.00 degrees ATDC.

Installed Exhaust Centerline is 106.50 degrees BTDC.

LSA is 109.3 degrees

Overlap is 29.00 degrees.

6G74 Intake camshaft & 6G74 Exhaust camshaft

Intake Opens BTDC 11,5

Intake Closes ABDC 60,5

Exhaust Opens BBDC 43,5

Exhaust Closes ATDC 20,5

Intake Duration is 251.00 degrees.

Exhaust Duration is 243.00 degrees.

Installed Intake Centerline is 114.50 degrees ATDC.

Installed Exhaust Centerline is 101.50 degrees BTDC.

LSA is 108.0 degrees

Overlap is 31.00 degrees.

Hope someone can give me an advise which cam setup could be good and for which specs I should look, like "is a wider LSA, better for a NA engine or not".

Best regards Jessy

No one can help or can give an advice?

As a general guide, shorter duration for lower rpm torque, longer duration for top end.

I don't know that engine, so about the best suggestions I have are to

a/ check out the spec's of the aftermarkte 'upgrades' to see how your selection compares.

b/ Check out the forums for that vehicle and/or engine and see what's suggested there.

@Gord, thank you for your answer! So should I use only shorter duration or only longer duration for intake and exhaust or is mixing them a bad idea?

The car and engine in my version isn't that known around the world. There are some aftermarket camshaft for the twin turbo Version for the Mitsubishi 3000GT (also known as GTO in some markets) like 264/272 or 272/272.

I am not yet very familiar with camshafts and am unsure whether such a set is good for a naturally aspirated engine or not even brings disadvantages...?

Longtube headers are installed, so a nice set of camshafts would be great to get more out of the engine.

Best regards

Jessy