That was the standart 454 ,,,not the magnum !!!!!

And it was not called 454 ,,it was called 7.4 liter 330 HP !!


Which was a standart 2 bolt 454 block and the mag had 4 bolt main and better internals after that they came out with the 525 SC based on the mag and also the HP 420 !!! Which had 400 HP ,,then they whent into the 502's and greated the HP 465 and the 500 !!!

they did make a 454mag for a few years that was just a standard
454 330hp with a Mag aircleaner. It was the one they put in front of Alpha drives.

I have a friend with an 1987 28 foot sleek with a 330 454 mag and a alpha.

Hey,,,its a 454 but not a magnum !!!!!!!!!!!!!!!!!!!!!

if it has the flame arrestor from a magnum does not make it a magnum !!!!!!!!!

ITS A 454 (7.4l) ,,,330 HP !!! diffrent intake ,,diffrent rockers ,,diffrent carb.


Its just a marinised 454 chevy engine with 330 hp. Used from MERC.

1987 mag was 330hp oval port, the one you have is rec heads which will work fine for 500hp. you have good parts to start. you should call or email DEAN GELLNER AT 216 398 8500 OR EMAIL AT [email protected]. he would go over the lower end of the motor to if theres a lot of hours. he would install new hyd roller cam kit since you have a flat tappet hyd cam. pocket porting heads, valve job, and a marine carb or custom race carb both marine. and either a stock single plan intake or a custom one. you would be at 500 to 550hp with the custom stuff maybe higher. I did that with my 502 it was stock 390hp at the prop you are 350hp at the prop. if you want aftermarket heads he can do that too. but I made just under 600hp. that same motor with a 850bg custom heads and bigger cam made 650hp then with custom 1050dom carb made 670hp. Dean is going to change cam/intake custom and we will pick up between 40 to 70 hp depends on cam. so I would give him a call his motors last a long time.

sorry DAREDEVIL but for the 1st year they called them mag with the alpha drive it was 1987 then in 88 they started 454 330hp and mag 365hp with the good parts, I had looked at a baja 240 sport in 90 and it had the alpha drive said 454mag 330hp. that was the last year of the trs 370hp 454, thats the motor the 365 mag replaced and drive with the B1. now tell this guy to call DEAN.

$hit,,,your suposed to back me up .LOL

i did not know about that first year thing.........SORRY !!

But after that i was right. LOL

The 87 454 magnum was a alpha drive motor and was basically a 330 with small heads. The next year 88 the Magnum came with a bravo and was a 365 with rectangle port heads.

Man look what I started.

You guys are great!!

Mine is not 330. It has rectangle port heads etc. I just didn't know how many horse it was. If the efi model is 385 is making 20 more horse with just the fuel injection? I planned on exhaust intake and roller cam just didn't know how far that would get me. Tossed around the idea of a pro charger but a guy who's upholstery I'm doing said his mechanic near LOTO said he would install a procharger but seriously does not recomend them. Are they not any good?