5.0 mercruiser block replacement

[Ostkuste]

Hello guys I’m new here and have a question about replacing my 1999 5.0 carbed engine that has a busted block/ bought the boat this way for real cheap
Serial # L357712
1. Is this a considered a Vortec engine/block?
2. If so what year GM blocks would be the same
96-99 or ?
3. I would like to step up to the 5.7 if all the outer parts would bolt up?

Thanks for any help in advance

 

[achris]

1. Yes, that engine has Vortec heads.
2. Scott Danforth , over to you...
3. Yes, all other parts will bolt from the 5L to a 5.7

Chris.......

 

[Bt Doctur]

the 5.0 and 5.7 are from the same family. everything on either motor will bolt up. Most "vortec" motors use 4 bolts down the center of the valve cover. If you go with a 5.7 the extra 60 hp make a great improvemnent

 

[Scott Danforth]

The 5.0 vortec heads are different than the 5.7 (combustion chamber, valve size, port size). All small blocks are externally identical. So your accessory drive, electrics, etc will all transfer over.
you may want to go to a better carb than what was on your 5.0

For a 5.7, the vortec motors are 1996 and later. In the marine world, its also when the roller cams were used, however most trucks had roller cams sine about 1990

Are you looking at a salvage yard motor or a recon, or building one?
if your building one, you can build a 383 for same cost as a 350

 

[Chudwick]

I’m in the middle of a real s**t show with a 5.0 right now and looked into a 5.7 swap. I have read about some people wrecking their alpha 1 outdrives due to the increased torque so do some research before you take the plunge.

 

[Scott Danforth]

If someone wrecked an alpha with a stock small block, they neglected the drive. I have personally witnessed 450hp strokers in front of alpha drives

 

[Ostkuste]

Thanks guys for the input and just wanted to be sure before I start the search for a 5.7 vortec to replace this 5.0 with, The boat is a 24 foot Bayliner rendezvous so Im sure it will like the upgraded power and if I have to change the prop or gearing im fine with it.

 

[Ostkuste]

Scott ill be looking for a low mile used engine from a 1999 or so chevy express van. Vin code R

 

[Scott Danforth]

Vin code R is simply a 350, found in anything from trucks to vans, etc.

any 1996 or later 350 would be fine, as you will be only using the short block. you will not be using the truck water pump, intake, accessories, starter, ignition, or intake/induction. as none of that stuff is marine. so sell that off or dont buy from the yard.

if you find a truck with a manual trans, you can use that flywheel.

you will need to replace all the core plugs with brass or stainless. you will need to replace the head gaskets with marine.

i use car-part.com to locate motors. or the local LKQ.

assume $300 for the motor, $11 for the core plug kit, $6 for permatex #1 to install the core plugs, and about $100 for a gasket set.

just as an FYI - its about $3000 to build a motor out of brand new parts (new block, new heads, new rotating assembly, etc) and the difference between the rotating assemblies for a 3.48" stroke (5.7 liter) and a 3.75" stroke (6.2 liter) is about $20

 

[Ostkuste]

Thank you scott, all good stuff to know, I live a few miles away from a copart so im hoping to find a low mile engine there from something.

 

[wellcraft-classic210]

Ostkuste
Hope you don't mind a related question to you post

Has anyone posted or seen a good bill of materials for the famed " 383 stroker " engine in new parts ?

It would be nice to have on for those of us that dream about going that route for the first time.

Having that along with some practical advice predicting re-propping and or re-gearing would make a spectacular sticky

 

[Scott Danforth]

Has anyone posted or seen a good bill of materials for the famed " 383 stroker " engine in new parts ?

Ive posted it a few times. GMPP block and vortec heads thru places like Scoggin Dickey, SCAT rotating assembly, Comp Cams XM270HR k-kit

 

[Scott06]

Would definitely recommend stepping up to 5.7 in a carb motor like this. If your intake is roached I would also consider stepping up to a 4 bbl intake and an edelbrock 1409. I did this on my 4.3 to 5.0 swap a couple years ago, throttle response compared to any 2 bbl boat I had is amazing, easy to set up, and you can use the throttle bracket off a 357 alpha with a Weber carb (edelbrock is copy)for a factory throttle linkage and slave solenoid bolt up.

On the drive ratio my experince was counter to what you read a lot that you have to regear the drive. I kept my 1.81/V6 ratio and workes perfectly by pitching up from a 19" to a 21". I suspect the drive ratios are based on keeping most applications within the typical 17/19/21/23 prop pitches. You probably have a lower pitch prop (17?) on a 24 ft with a 5.0 now?

 

[Ostkuste]

Yes it has a 17 prop right now, and I have thought about 4 bbl upgrade on the 5.7

 

[Bondo]

and I have thought about 4 bbl upgrade on the 5.7

Ayuh,...... It'll be "Noticeable",......

 

[QBhoy]

I’d defo go for the 5.7. At most you’ll need to change the prop a couple of inches. You’ll notice the extra 30/40hp for sure.
Domt worry about the Alpha one. Plenty of 5.7’s driving an Alpha one out there.

 

[Scott Danforth]

If going with a salvage yard motor to keep the costs down, stick with a 350. Maybe a cam change, however add a carb spacer for additional midrange torque. Definately go with a 4 barrel

If building a motor, i would build a stroker

 

[Scott06]

Yes it has a 17 prop right now, and I have thought about 4 bbl upgrade on the 5.7

You'll probably be able to swing a 19" with a 4 bbl 5.7. When you get it together start with the prop you've got and see what the wot rpm is

merc part number 805359T is the throttle bracket to work with edelbrock/Webber carb if converting from a 2 bbl.