350 mag upgrade

[smokediver]

It's lookin like my boat isnt gonna sell so i was wondering if anyone has done a cam/head swap on a 350 mag mpi . I was thinking about going to the newer small port bowtie heads and going with a comp cam xm270hr . Low hour motor so i am not really concerned with the bottom end . Do you think the fuel injection will handle the upgrades and do you think it would be possible to re-use the roller lifters i already have ? I am thinking this should be a 50-70 horse upgrade .. Mr. Poodle , are you still in touch with the guy that builds alpha drives ? might need to upgrade to a HD gearset .. Thx in advance .

[The Hedgehog]

If you have a MEFI ECU someone may have a cal. If you have a PCM 555 you are out of luck. Whipple can lean it a little but not program it for the cam and heads.

One of the techy guys here can advise you on the cam specs/exhaust issue.

[mrfixxall]

smoke, give bob a call at marine kinetics,he can help you out on a cam,he can custome grind you one for the same price as if you were going to buy one off the shelf..plus his blanks are billit not cast..

RMBUILDER"/Bob Madara of Marine Kinetics in N.Y. 585-654-8583

he knows his stuff!!!:)

[The Hedgehog]

smoke, give bob a call at marine kinetics,he can help you out on a cam,he can custome grind you one for the same price as if you were going to buy one off the shelf..plus his blanks are billit not cast..
RMBUILDER"/Bob Madara of Marine Kinetics in N.Y. 585-654-8583
he knows his stuff!!!:)

I have heard that too. Look around here. I think he has posted before.

If you got PCM555 it is probably easier to go to a carb

[mrfixxall]

I have heard that too. Look around here. I think he has posted before.
If you got PCM555 it is probably easier to go to a carb

Cant he just pull the chipout and rewrite it?

[The Hedgehog]

Cant he just pull the chipout and rewrite it?

No sir, not the 555.

Got to have the MEFI for that

[smokediver]

yeah , i have the 555 but as long as the timing advance , ect is in the ballpark i don't see where there would be a problem . I used a stock merc tbolt4 ignition off a 250 horse 5.7 on a 430 horse 383 in my 16 and didnt have any issues at all .

[mrfixxall]

yeah , i have the 555 but as long as the timing advance , ect is in the ballpark i don't see where there would be a problem . I used a stock merc tbolt4 ignition off a 250 horse 5.7 on a 430 horse 383 in my 16 and didnt have any issues at all .

Smoke, i believe what hedge is saying is you cant prograhm the injector puls width,how long the injector needs to be open to allow the proper fuel in..

i would call bob hes a guru when it comes to cams,he will blow your mind with his cam knolege..he can desigh a cam to work with your pcm so no prograhming may not be needed..or bolt on the heads and run 1.6 / 1.7 rockers..

[smokediver]

to go to a different rocker on stock vortec heads , the pushrod holes need to be machined and i don't think just doing the rockers is going to give me the power i am looking for . If I have to go the carb route i very might just sell my engine sans accessories and go the 383 route again:bonk: . As much as I enjoy the turnkey set up i have now , i really miss the acceleration of my 16 !

[mike o]

Your 16 was a boat I wished I had bought. Ever see it around?

[mrfixxall]

to go to a different rocker on stock vortec heads , the pushrod holes need to be machined and i don't think just doing the rockers is going to give me the power i am looking for . If I have to go the carb route i very might just sell my engine sans accessories and go the 383 route again:bonk: . As much as I enjoy the turnkey set up i have now , i really miss the acceleration of my 16 !


Bravo or alpha? a 1.65 ratio will give you better acceleration:)

[smokediver]

Your 16 was a boat I wished I had bought. Ever see it around?
I used to see it but i think the guy that bought it ran into a little trouble , lol.. I have a alpha 1.62 drive gonna switch over to a 1.47 hd gearset soon