new engine

garyoja

Seaman Apprentice
Joined
Jun 7, 2013
Messages
37
i recently had a vortec 355 built its around 9.4:1 comp with a comp cams extreme marine 270 hydraulic roller do you think the cam will be ok as far as reversion goes ?
 

Bondo

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Apr 17, 2002
Messages
70,465
Re: new engine

Ayuh,.... At 1500 to 5500 rpms, Ya it's atad Tall for a boat motor,...

It may struggle to get outa the hole, 'n reversion is a possibility,...
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
Re: new engine

It's PERFECT. That's the one I would order. Has the maximum amount of cam you can run without resorting to reversion prevention. At least according to the documents.
I'd still run it at idle and shut it off without revving, then pull the risers for a look to see if there is water laying in the exhaust manifolds. Just because it's at the Lobe Separation Angle limit of 112 degrees.
I'm jealous of your motor, I have a flat lifter stocker, it's an anchor compared to what you have there. Worse thing is they are very similar til you get to the cam and the rebore.
You are gonna be fast and reliable with that.
Warm it up before running at high rpms, and avoid wide open throttle holeshots. You are getting to the torque maximum for the drive.
Enjoy it, I'd be stoked to have that motor.
On edit. Really Bondo? I didn't read it that way, comp calls that their middle cam, the wild stuff is bigger still. I am still learning and you are the guru. What's the reversion likelyhood with 112 LSA?
 

garyoja

Seaman Apprentice
Joined
Jun 7, 2013
Messages
37
Re: new engine

Ayuh,.... At 1500 to 5500 rpms, Ya it's atad Tall for a boat motor,...

It may struggle to get outa the hole, 'n reversion is a possibility,...

i have seen the dyno sheets on the sam build it was already making 340 ftlb @ 2000 rpm and made a max of 410 @ 4200 if i remember right . the boat has always been a tad slow out of the hole as it came stock with a 23 pitch cleaver and that was with a stock 260 hp 350 . so this cant be any worse imho .

and as NHGuy says do you really think there is a posibilty of reversion with 112 lsa ? this is not that big of a cam compared to some that they offer
 

Bamaman1

Lieutenant Commander
Joined
May 15, 2011
Messages
1,895
Re: new engine

Only thing is that you'll probably need a good prop shop to advise you on what propeller to use on your hull.
 

garyoja

Seaman Apprentice
Joined
Jun 7, 2013
Messages
37
Re: new engine

Only thing is that you'll probably need a good prop shop to advise you on what propeller to use on your hull.

ill prolly keep the same one for now as im broke now lol. id like to see more speed out of her not much for good shops here i wish i could try a few different ones maybe a 26pitch
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
Re: new engine

It's built, give it a run. I can tell you get it about a lot of this stuff, and you are looking for experience and input. If you try to start it after a run & it's hydrolocked it will just go thunk and won't crank. If that happens. don't force it, it's time to change the cam.
Those HP & TQ numbers sound pretty high, I'd expect a little less with marine exhaust, I assume the motor was dynoed with performance car exhaust.
 

garyoja

Seaman Apprentice
Joined
Jun 7, 2013
Messages
37
Re: new engine

yes it was dynoed with open car headers deff not stupid boat exhaust:blue: lol on the bright side she is not to heavy only 2700 lbs .
i had a 72 z28 when i was younger with a big cowl hood we got a nasty nasty down poor one night and it actualy made its way into the engine . it hydro locked bent a rod on a fresh 383 . i was not a happy camper .
 

garyoja

Seaman Apprentice
Joined
Jun 7, 2013
Messages
37
Re: new engine

It's PERFECT. That's the one I would order. Has the maximum amount of cam you can run without resorting to reversion prevention. At least according to the documents.
I'd still run it at idle and shut it off without revving, then pull the risers for a look to see if there is water laying in the exhaust manifolds. Just because it's at the Lobe Separation Angle limit of 112 degrees.
I'm jealous of your motor, I have a flat lifter stocker, it's an anchor compared to what you have there. Worse thing is they are very similar til you get to the cam and the rebore.
You are gonna be fast and reliable with that.
Warm it up before running at high rpms, and avoid wide open throttle holeshots. You are getting to the torque maximum for the drive.
Enjoy it, I'd be stoked to have that motor.
On edit. Really Bondo? I didn't read it that way, comp calls that their middle cam, the wild stuff is bigger still. I am still learning and you are the guru. What's the reversion likelyhood with 112 LSA?
your baja is a pretty sweet boat dude . love old boats . and boats in general . when i was 19 i worked for cougar boats here in canada before tom sold to some american buisness men all the boats were hand laid no chopper gun . thats when my love for boats started . my dream boat is a 90s 23 foot cougar mtr with a 300 out board very very fast boat with sweet lines
 
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