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Leprican28 07-08-2011 03:48 PM

415HP 454 Build Question
 
Im new to the performance boating world and my first project is a 1990 Baja 250 ES. The previous owner claimed he did a mild build to it and says it has 415HP. I was wondering what I should look for that would indicate this. The block casting # is 1401544. The heads are 3933148(Open 2V/427 265 122.1cc) It also has roller setup. Like I said, im a newbie and right now i just really want to know what I have so I can go from here. Oh yeah, and its running Thunderbolt IV ignition.

jeffswav 07-08-2011 04:38 PM


Originally Posted by Leprican28 (Post 3447794)
Im new to the performance boating world and my first project is a 1990 Baja 250 ES. The previous owner claimed he did a mild build to it and says it has 415HP. I was wondering what I should look for that would indicate this. The block casting # is 1401544. The heads are 3933148(Open 2V/427 265 122.1cc) It also has roller setup. Like I said, im a newbie and right now i just really want to know what I have so I can go from here. Oh yeah, and its running Thunderbolt IV ignition.

Here are the head specs from Mortec 3933148....69-84...oval...OPEN...'69 396/265hp, 366T, 427T, 112cc chamber
Those should be the large ovals, but there is more to it than that. You must be missing a number on your block 14015445...454.......78-90...2 or 4 bolt
What cam, exhaust, carb, pistons do you have? With a roller cam you can easily get 450hp with good exhaust.

Leprican28 07-08-2011 05:15 PM

Factory wet exhaust. Throttle body injection with thunderbolt ignition. I'm in the process now of tearing it down some more. 14015445 block

jeffswav 07-08-2011 06:42 PM


Originally Posted by Leprican28 (Post 3447829)
Factory wet exhaust. Throttle body injection with thunderbolt ignition. I'm in the process now of tearing it down some more. 14015445 block

Fuel injection ? Aftermarket ? Good luck on your tear down.

endeavour32 07-09-2011 10:33 AM

If your boat is using the stock fuel injection don't attempt to modify anything. You will open a can of worms that you will later regret opening. The computer is set-up to run with very specific components. Change one thing and everything is off.

BAD ASS SCARAB 07-09-2011 11:15 AM

Endevor your right
 
I have to side with Endevor on this. Especailly the cam. There is certain time frame on your the pulse width on the firing of your injectors. The Cam has to be calibrated for the proper opening and closing of the intake and exhaust to the proper timming of the injectors.
You slap a cam in this that is not matched to the fuel system and your going to have one doggy ass motor or a motor that won't run at all.

If you want to freshin it up tear it down and check all the part numbers for your cam pistons etc and call some marine engine guys and check all the componets that you have. If it runs good with the set up then stick with it just freshin it up with the same componets that you have. Just go new.

Also make sure if there old castings on the heads that you have harden seats on the valves if you have the original seats on the heads they were built for leaded fuel. The no lead fuel will littlerly pound out the seats and turn the valves into somthing that looks like a mushroom. If your not sure have a reputable maching shop install new stainless valves and harden valve seats. And while your ad it have new valve guides installed.

Leprican28 07-09-2011 01:44 PM

Thanks for the help guys! The wifey has me doing home projects this weekend but i plan on pulling the motor all the way out next week sometime. I did look into it a little further last night and actually is does NOT have a roller cam and it has been bored .030 over with flat top pistons. Hopefully next weekend i will be able to post some more specifics on the cam, pistons, crank, etc.

BAD ASS SCARAB 07-09-2011 03:12 PM

Sweet sounds like sombody dropped some cha ching in the motor. Good for you!

Leprican28 07-23-2011 04:48 PM

Started new thread

http://www.offshoreonly.com/forums/g...ml#post3460258


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