Will old out drive hold up to a fresh motor?

[steltenkamp]

Rebuilding a 1978 350ci 260hp motor in my 78 Century boat.

long story short. The build snowballed. I now have a 350 bored 40 over with 94 64cc heads. Running dished pistons to keep copresson down.

running a little bigger on the cam, and fuel injection.

I think I have a 1.50 pre alfa drive. 260 with the eye hook on top.

planning on going through the unit, but is it worth it?

Have been told it was week stock in 78. I have a friend with a Bravo 1 drive for sale cheap. But didn't know if i can make it work.

I know it can work, but at what cost?

any help is better than no help.

 

[180shabah]

Re: Will old out drive hold up to a fresh motor?

040 leaves you a little thin for marine duty, treat it gentle.

was water reversion a consideration when the cam was selected?

what is the power output of this "new" engine?

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

If the out drive is in the same shape as the motor was, I'm going to go far. I thought the motor was ok.

other than some blow buy and low compresson on the cylinders.

Turned out i had two broken rings. both heads cracked, worn cam and lifters, timing chain about to jump, and all bearings throwing brass on my pan when i pulled it to ( FRESHIN UP ) : )

can't pay don't play: )

 

[180shabah]

Re: Will old out drive hold up to a fresh motor?

if the drive is bad you can buy a brand new SE106 probably cheaper than you can rebuild your old one.

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

was told since it was a marine block it souldn't be an issue.

Therostat is 140 and i never got over 190 idling around.

Which makes me think, why have a thermosat in a boat? Maybe a dumb question, but it is late.

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

would that bolt to my gimble housing or would i have change that?

What would i have to do to make a Bravo I work in my boat?

 

[Don S]

Re: Will old out drive hold up to a fresh motor?

040 leaves you a little thin for marine duty, treat it gentle.

I agree 100% But think about this. All these rebuilt engine sites that sell chea......... uhhhhh, inexpensive long blocks, don't spend a lot of time measuring and fitting.
They bore .060 and slam it together. How else can you make money at long blocks for 1500 bucks.
Funny thing is, Mercruiser, OMC (when they existed) and Volvo, do not recommend boring over .030 and don't even sell parts like rings & pistons for anything over .030 overbore.

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

and cam is a marine cam from comp. just a bit higher lift and deration than stock.

not out to win any races, just want a reliable boat.

was fun running 50 in a $600 boat next to some 20k pluse boats! : )

That's why she is called cheap thrills: )

 

[180shabah]

Re: Will old out drive hold up to a fresh motor?

was told since it was a marine block it souldn't be an issue.

There is no such thing, it is just a 2bolt sbc

Therostat is 140 and i never got over 190 idling around.

190 is high and you are at risk of burning rubber exhaust components. How much hotter will it be when you get a load on it.

Which makes me think, why have a thermosat in a boat? Maybe a dumb question, but it is late.

Thermostats control MINIMUM temperature, doesnt matter if it is a car or boat.

would that bolt to my gimble housing or would i have change that?

Direct replacement, no other parts need changed

What would i have to do to make a Bravo I work in my boat?

Swap everything, inner transom shield, gimble housing etc....

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

Also should say. The guy doing the machine work is very good.

Having all rotating asm. ballaced and rods heat treated.

He wanted to go 60 over, but i thought i'd leave room if i needed it!

Hope i don't!

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

Was really suprised that it was a two bolt main.

Does that mean a four bolt main truck motor is better?

I know in car terms it is, but in marine didn't know if was different.

Like water jakets and cyliner wall thickness.

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

and if i a'm using a fuel enjection system. wouldn't you want the min water temp.

which is around 60 for me.

ok , dumb question. it late and i tierd.

thanks for the info!

 

[bruceb58]

Re: Will old out drive hold up to a fresh motor?

Curious...what are you using for fuel injection?

 

[ENSIGN]

Re: Will old out drive hold up to a fresh motor?

I would trust the outdrive before I would trust the old coupler

 

[180shabah]

Re: Will old out drive hold up to a fresh motor?

He wanted to go 60 over

Why did he want to .060, either the block was that worn or it wasn't

Was really suprised that it was a two bolt main.

Does that mean a four bolt main truck motor is better?

yes a 4bolt caps will hold together better at high rpms, but this marine engine will never be spinning above 5k. Much less stress than at 6500....

Curious...what are you using for fuel injection?

Ditto?

 

[Fishermark]

Re: Will old out drive hold up to a fresh motor?

Does that mean a four bolt main truck motor is better?

I know in car terms it is, but in marine didn't know if was different

Actually tests show that a four bolt main is really no stronger than a two bolt main. Very little difference anyway. A splayed four bolt main, yes, but not a "regular" four bolt main.

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

The Old motor Had some small pits in the wall froom rust. He said that after last honing it was fine. But at first thought that might have to go .60 over.

The fuel injection is a old B&M Superjection system. Four Injectors on the plate. Using a Mass air flow reading and tunable PMC.

Of coarse I am going to use a Marine Fuel pump.

It was free and thought i would give it a try, If not replacing the pitted Quadrajet.

And the coupler has to be changed, it about to brake loose now.

Thanks for the intrest and i'll keep ya all posted. For help or at least a laugh: )

 

[bruceb58]

Re: Will old out drive hold up to a fresh motor?

The fuel injection is a old B&M Superjection system. Four Injectors on the plate. Using a Mass air flow reading and tunable PMC.

If this is not a marine fuel injection, don't use it.

 

[steltenkamp]

Re: Will old out drive hold up to a fresh motor?

I contacted the company that has now taken over the the B&M, Airindustries.

Was told by them the only thing that needed to be used is a marine fuel pump and K&N filter. That are approved for marine use.

has inductive pickup on crank and no other spark control.

The PCM will be mounted away from motor and any possable water spray, Should be ok, parts are still avalable.