whats the difference 7.4 310hp

[DAULEY]

what is the difference of 454 310hp and 454 365 hp i have a person that wants to trade 99 zx26 but it has a 310 hp and i thought it would be a dog how much would it cost to get more hp
thanks bob

[Wildfire]

First, I am not an expert.

However, I believe some of the differences are cast versus forged crankshaft, peanut port versus "much better" cylinder heads and other major things. Sorry I don't know more, but I know that some others on the board know a lot more and hopefully they will put their $0.02 in.

I think they both have 4-bolt mains though, if it is Gen V or VI.

[DAULEY]

need so help here

[roadking]

all I know is my 22ZX w/350 mag-300hp barely breaks 60mph. From previous advise on this site, I would'nt buy it!

[roadking]

all I know is my 22ZX w/350 mag-300hp barely breaks 60mph. From previous advise on this site, I would'nt buy it!

[Scubado]

I can't help on the differences of those two motors, but you may be under HP even with 365 HP.

50 HP may equate to five MPH if you are lucky. I'd be surprised if you could break 60 MPH with that boat and 365 HP(I do not own a 26, so take that as pure speculation). That said, I think a lot of folks on this board have had great luck with blowers on that motor. Five or Six thousand gets you a 70+ MPH boat.

[Gary]

The 365 is the magnum motor with the better internals. You can upgrade this motor if you need more speed. The 310 is the base 454 cast internals not recommeded for upgrades. It can be done but like I said not recommended. My take is unless you get a real good deal the 310 will not be enough and then you really can't add to it MY .02

[DAULEY]

its a 99zx26 for 34000 with 310hp 454with 150 hrs
thanks for the insite

[Lil Grizz]

Just thought I would throw in my .02 here. The 7.4 310 is very sluggish. Its not a bad engine just not exactly worth getting if you can avoid it. My 22zx came from the factory with the 7.4-310 and would run about 62mph on its best day. The basic engine is still in the boat with the exception of the supercharger I added. The short block is the 7.4, I changed the heads to the 97-98 peanut port design because the 7.4 mpi heads have a fast burn design which detonate under boost. The heads are no better than the originals just safer for my application.
As far as the engine itself its not a bad piece. It has a 4 bolt main (trust me I know for sure) the crank is cast, and in my opinion the weak point lies in the connecting rods. The rods are definately what will come apart first. The camshaft is milder than the magnum and because of this the engine has little get up and go. Its durable contrary to what many say I have 3 hard seasons on mine with the blower (makes about 500 hp) and the engine hasnt had a problem yet. No smoke, no unusal oil consumption, no loss of compression. That is mostly due to my ECU tuning. If I could have had the Magnum I would have but at the time I couldnt locate anything but the 7.4 in 6 months of searching within my price range.

Basicaly the 310 is for those people who want a big block but have no real intrest in performance. If you have other options I would go with them because there is much less work needed to be satisfied.