454 330 or 454 mag

[thanks_don]

Hello I have 1990 24ls with a 7.4 330 .. not the fastest but it runs great.. Hears my question is my block as good as a 365 mag block for rebuilding . Iv read alot of your posts and the 365 mag has stronger parts [harden parts ec.] also heads are better, I sure could use your guys advice on engine.. FORMULAS.. Thanks guys

[RaggedEdge]

Originally Posted by thanks_don

Hello I have 1990 24ls with a 7.4 330 .. not the fastest but it runs great.. Hears my question is my block as good as a 365 mag block for rebuilding . Iv read alot of your posts and the 365 mag has stronger parts [harden parts ec.] also heads are better, I sure could use your guys advice on engine.. FORMULAS.. Thanks guys

Here you go guy;

454/330 hp = 2 bolt main bearing cap block, cast iorn crank, stock rods, cast pistons, small valve oval port cylinder heads.

454/365 hp = 4 bolt main bearing cap block, forged steel crank, forged steel rods, forged pistons, larger valve rectangular port cylinder heads.

454/330 is the low perf version, very durable and reliable in it's intended form. 454/365 is the high perf version, and a much better base if you intend to build some extra horsepower thru some modifications. The 330 hp was intended to run 4600-4800 rpm, while the 365 was intended to run up to 5200 0r so, if I remember correctly the rev limiter was set at 5250.

I had a Sea Ray Pachanga 32 with the 330's that I traded with 450+ hrs, and a 32 Velocity with the 365 Mags that I ran to 200+ before repowering, and sold them to a friend who I think ran them close to the 500 hr mark and that was three seasons ago, they are still going . Hope this helps........... Ragged

[thanks_don]

RAGGED THANKS FOR THE GREAT INFO ; MY 330 HAS 586 HRS , YOU'RE RIGHT IT IS VERY DURABLE AND RUNS LIKE A SWISS WATCH... I SHOULD HIT MYSELF IN THE HEAD WITH A BALLPEIN HAMMER BUT: 2 COOLERS 2 DUFFEL BAGS 5 GALLONS OF H20 2 LOUNGE CHAIRS & 800#OF FUEL , AND LET'S NOT FORGET MY LOVELY CO-PILOT = MORE HP !!!!! . OK LET'S TALK ENGINES ANY SUGGESTIONS ?

[ericaull]

If you want good reliable smooth turnkey power...think about a 496HO 425 hp....runs great! Good luck, ERIC

[cuda]

I'd run it until it pukes, then look for a good take out engine to replace it. Unless you're willing to dump cubic yards of bucks into the boat, the performance will be negligable. Keep clean oil in it, and have fun.

[thanks_don]

496HO HOT ENGINE ERIC THANKS, I'V SEEN A COUPLE IN THE CLASSIFIEDS FOR ABOUT 10K,NEW 496HO ? DROP IN SOUNDS GOOD FOR A NOVICE LIKE ME . THANKS N.Y. EEE

[thanks_don]

Cuda Thanks ... Ill Try To Squeezzze A Few More... Mps (miles Per Season) :d

1. Wax Bottom Of Boat
2. Check Prop At Shop
3. Less Ice

[cuda]

What exhaust do you have on it? You could swap to a better flowing lighter weight exhaust, and then still use it on your next engine. I'm about to put new Dana exhaust of the 454/330 in Debbie's 22 Donzi, until I get the Hp 500 for it together, then I can still use the exhaust.

[ericaull]

What Cuda said is very true ....I had a 1990 Baja 250ES with a base 454 in it....ran well forever I sold it in 2000 with 525 hours (225 when I bought it in 1993)...All I ever did was basic maintinance. KEEP the RPMs below 4800 don't over heat it and it will run a good long time. I thought you needed to change the engine and wanted to upgrade....

[sneekinfreek]

Would the volvo penta 740 duo prop have the same issues . Could I find a drop in 496 ho that would bolt right in place of the stock 454 330 hp