7.4L versus 454 magnum
 

my book for the boat shows these both as options, aren't these both the same displacement?? my boat shows 7.4l on the back of it, but is it a mangum or just a plain 454. the previous owner said it was a 360 hp, but i haven't found anything that would prove that yet.

Re: 7.4L versus 454 magnum
 

what year?most 454 mags are 365 or 385 hp. The reg 454 is 300 or 330hp

Re: 7.4L versus 454 magnum
 

1990 baja 210 ess, how do i tell if it has a mag or just the standard

Re: 7.4L versus 454 magnum
 

Check the block code. Front passenger side. XW=7.4, XA=Mag

Re: 7.4L versus 454 magnum
 

is there more numbers than that, or is that it?? i'm curious what this engine is now, the previous owner told me it was 360 hp, but i think it may be less now, which would bite

Re: 7.4L versus 454 magnum
 

Those are the last 2 letters in the code.

Re: 7.4L versus 454 magnum
 

that's part of the #'s. Mags have rect intake heads,high rise intake,4 bolt mains,bigger rods,forged pistons,and bigger cam.

Re: 7.4L versus 454 magnum
 

Easiest way I know is that a 454Mag will have an aluminum high rise intake, 305HP/7.4 will have a low cast iron intake...
If you have a Mag. in a 21', it must be quite the screamer!

Re: 7.4L versus 454 magnum
 

Quick test for HP intake, if it is magnetic it's the standard 454/310, if it's not then it might be a 454/Mag. However, someone could have put an intake and carb on it aftermarket, but that is unlikely.

Re: 7.4L versus 454 magnum
 

With 360 HP in a 21 footer you should be in the 70's(GPS) for speed.

Re: 7.4L versus 454 magnum
 

I think you have the Mag. Do you have an Alpha 1 or an Alpha 2. With the 2 you have 365hp with the One you have 330hp. I had a 87 23 Velocity with the 454 Mag, then that Baja came out and screamed past me. Worst moment of my life, me and 2 smoking babes cruising the Severn River, thius guy in the Baja pulls up, we drop the Hammer, all I can say is one of the women was asking "How come he's kicking your a**". Only time I ever got beat in that boat. Best day was taking on a guy with a 33' Center Console Scarab with Triple 200's, wasn't by much, but I got him.

Guy up on my brothers dock in Lake Winneapausakee just freshened his 454 in the same boat, now his wife won't ride with him!

Re: 7.4L versus 454 magnum
 

the plastic on top of the aircleaner says it is a 7.4l/v8 bravo, with thunderbolt ignition

the serial number of the engine is 0c767301, if that means anything to anyone, and the drive is a bravo one drive, i've had the boat in the mid to upper sixties

Re: 7.4L versus 454 magnum
 

I think you've got just the 7.4L (310hp)....most will say MAG on the cover. however the serial will tell the final story

Re: 7.4L versus 454 magnum
 

With a better set of heads, or some head work, and a new cam and exhaust you can bump the 310/330 up to around 400hp. What you have to watch is your RPMs They won't last iff you spin past 5000rpm.

also a better intake (has to match the heads) and carb

Re: 7.4L versus 454 magnum
 

would you know what cam to use to bump it a fw ponies. I have mine tore down, reworked and ready for assembly. Don't want ot open the money flood gates because plan on keeping boat 1 more season only then jump to 38. any idea's?

Re: 7.4L versus 454 magnum
 

do you have the stock heads yet? I'm not sure how this would work with the small heads, unless they are ported.. They may restrict this cam to much.
I am changing to a Crane 241, flat tappet, in my 454 mag.

Re: 7.4L versus 454 magnum
 

Hello Cloudmaster,

Welcome to the board! You bought DJ's boat right? My buddy was looking at it and ended up buying Wette Vette's (here on OSO) boat instead. It's a twin to yours....burgundy and black graphics. How are you enjoying the boat so far? Taken it anywhere besides the lakes in Madison? To answer your question....I believe that you have the 330 horsepower 454.

Re: 7.4L versus 454 magnum
 

Y'all realize this was a thread from June right? :D

Re: 7.4L versus 454 magnum
 

Payton, stock heads ,redone.