2BAD4U

Just curious how much boost and what combinations some of you are running? Stock motor? Build? If So how much and what do you have done. I am sorta new to the whole power boat thing but am well rounded in car area. I know there is a lot of load with boats vs cars and such fourth. But i'm wanting to raise the boost up on my built 509 but wondering the limits. I know it has a lot to do with timing, fuel and what not i understand that. But i really am asking if anyone is running 10psi or more on pump fuel and if so what blower, fuel and compression. Is the motor lasting???

Thanks
Ron

articfriends

iTrader: (1)

540, dart block, m-3sc,pump premium-92-93 octane, afr cnc'd heads, highly modified 502 mpi intake, custom twin rail fuel injection, 8.2-1 compression, 13 lbs boost made 1057 hp, 14-14.5 lbs boost made 1115 hp on a mix of 80% premium/20 % race gas. Motor made 657 hp with blower disconnected, dyno session had correction factor under 10% using the generous 60 degree std and was only turning raw water pump, Smitty

articfriends

iTrader: (1)

Didn't you post this question a few months ago and weren't you telling us about a 1400 hp mustang?

2BAD4U

SO... Your running 13psi on 8.2-1 on pump gas right? I have a 509 SRP Forged Blower pistons 8.5-1 and Scatt rod's. I wanted to take my M-3 from 5psi to around 10. Some dude at AZSM said it will pop and i'm crazy. I understand cars and boats are kinda like apples and oranges. I understand that boats are under more load and you are at higher rpms for longer periods of time. But I can take a 9.0-1 motor in a car and throw 14 lbs at it and have a 17 degrees of timing in it and not have to worry about detnation. So i couldn't see why I would have problems. I just put cometic head gaskets in and pro comp aluminum heads and studed them in. I can't imagine that i would see detnation with 91 oct. on 8.5-1 motor on 10psi at 6,000 elevation with only 8 degrees of total timing. But my buddy who has a Baja like mine but a 454 m3sc who is only running 3psi says i'm crazy.

2BAD4U

No not me. Must be someone else. I personally can't stand mustangs. But do have a Camaro with about that much HP.

Rookie

iTrader: (4)

With AZSM's history of tuning I can see why they say it would pop. You can judge for yourself.
http://www.offshoreonly.com/forums/b...ed-marine.html

2BAD4U

LOL I have heard a lot of bad things about them myself. Funny to see that. Thanks! But yeah... I wouldn't let them touch my ****. I just called them to ask them if they have heard of anyone running a decent amount of boost on any motors or if they have. The dude there said 7psi at most. And was sorta dickish on the phone. He had a sale of some heads and cemetic head gaskets but was to stupid to call me back. So i said to hell with em.

articfriends

iTrader: (1)

I'm pretty sure you could run 10-12 psi of boost with your set-up (I assume you have a aw504 innercooler or equivilant) BUT to do it safely it should be tuned in the boat or on the dyno where someone can watch for knock from the knock sensor and afr on a 02 sensor then adjust the fuel tables/timing tables accordingly. As far as your only running 8 degrees of total timing, I think you might be refering to the base timing set, the efi adds more timing to the base number as it sees fit, Smitty

2BAD4U

Yeah i was... I do have a wide band currently hooked up. I have the after market Holley computer with lap top software. I do have the bigger 504 innercooler as well as i just hooked up a water meth kit that i forgot to mention. That will be boost activated at 5psi. Which should bring AFR'S down one full point. Which on 50/50 mix is like 112 oct. Now Smitty sounds like you have a really nice boat. "I'm jealous" Please tell me what else can i do to my boat to make it faster. I heard of some cone or something that goes on i think the outdrive. What is that? and i have heard of some plate or something that i think people add to the back half of the bottom hull of the boat. What is all that stuff? Oh... I do have a built outdrive with 1.50 ratio.
Thanks Ron

articfriends

iTrader: (1)

Ron, not much I have ever done as far as set-up has ever worked for me other than making more power. My well blended hydromotive nose cone was worth 3-5 mph after boat went faster than 85 mph, labbed finished props are usually worth a mph or 2. Everything else I have done-exstension box, -2 inch shorty, 5 blade rops, spacers etc have all either slowed the boat down or made it unstable/ill handling, Smitty