|08-22-2008 09:08 AM|
Someone started up an old one here boys! Its my thread originally, not sure why it got revisited, but yes, I have been running this engine for 2 or 3 years in the boat. It runs great! I blew my outdrive gears twice the first year with it, so more power isn't really an option. I finally bought a new aftermarket Alpha drive from SEI, which has held now for 2 years. Factory intake, stock Q-Jet with bigger jets and rods in the secondaries, and a high flow needle and seat. I have open exhaust now on the stock exhaust manifolds which doesn't really provide any more power but sounds badd *** with this motor! Anyway, motor runs great, and this old boat and alpha outdrive probably can't handle any more power anyway. I will say, its the fastest 1984 24 foot small block in this area!
|08-21-2008 01:28 PM|
|08-21-2008 12:47 PM|
|454C10||These engines take time to build. hahaha|
|08-21-2008 09:34 AM|
|Double_v23||This thread is 4 years old, I hope he has it all figured out by now.|
|08-21-2008 09:19 AM|
I get 9.72:1cr.
8cc head gasket
4cc deck height
you will be on the edge of detonation with 91 octane if the engine runs hot.
Yes, those manifolds are killing at least 75Hp. That could be a 400hp engine with headers and a performer rpm intake. You might consider adding bigger jets in the primary's and some richer rods in the secondary's.
|08-20-2008 07:39 PM|
|gregb||How often do you use the boat? If it's not a lot it'll take an intake a while to corrode, you can have it hard anodized or at least powder coated that will reduce the corrosion. A manifold and carb would really help. The exhaust is another place for improvement, but your right, $$$$$$$$. My boat has Bassett headers so I'm not limited there. Even without that stuff though your combo should put 325HP without much effort. What drive do you have, is it up to the task? That 260 HP stock rating is at what RPM, you may have to re-prop also.|
|08-17-2004 06:34 AM|
|stepside454||a better intake would help up top, like a Perfrormer, as for the exhaust, I really dont know about your boat exhaust, so, no idea really.|
|08-16-2004 09:14 PM|
I could live with that. Considering that the stock motor was a 350 rated at 260HP. What happens if I change the intake/carb and/or exhaust? I am assuming those are my bottlenecks, but I am kinda limited in both of those departments since it is a boat. Aluminum intakes seem to corode in boats, and aftermarket Marine water cooled headers are like $3000!
Cant wait to get it running and back in the water!
|08-16-2004 09:00 PM|
Tommy ,I get pretty close to that on DD2000, although I had to make an assumption with the prop exhaust.
I get 330 HP @ 5000 RPMs & 381 ft. lbs. @ 3500 RPMs
|08-16-2004 08:01 PM|
9.5-1 383SBC with world product sportsman II's. Power guess?
Well I bought the World Products Sportsman II's for my 383 project. They are 200cc runners, 2.02 valves and 72cc chambers. with -6cc flattops I should be at 9.5-1 I am using a Comp Marine cam that is 218/224 @.050 462/477 lift, 112LSA. I'm putting it in a boat so it will never see a dyno. Any guesses? I am running a stock q-jet intake and carb with stock Mercruiser thru prop exhaust. The ignition is Mercruiser Thunderbolt IV which is similar to a Mallory unit. It has an electronic pickup inside the dist and a spark box mounted to the side of the engine. I would think it would have to be at least 325hp???