S&J Longblock for replacement. Anyone used them?

Just looking at user feedback for anyone who has ordered from them (a full long block).

Most all builders and rebuilders use the GM Full Dished pistons in their versions of a SBC Marine Engine.
This piston profile came to be in the early 70s as to meet US emission control standards.
It worked for automotive use, but it is a lousy choice for a SBC Marine Engine.
It has been continued because they are inexpensive, one piston p/n fits all 8 bores, and the guy installing the pistons on the connecting rods can be drunk or high while doing so.

Take a few minutes and read this thread, starting at post #7.

http://www.marineengine.com/boat-forum/showthread.php?394668-V6-to-V8-engine-swap

The cost to build one using a much better piston profile will run you about $200/$300 more only.

What engine and what year? GM or Ford?
I looked at their site and the drop down menu sucks for marine.......

Disregard old dished piston moron, He has no input here.....He just likes Post count, PCR

kghost said:

What engine and what year? GM or Ford?

Click to expand...

​Its a 1977 Bertram with twin GM 250s (inline 6s). I'm replacing the outdrives with Mercruiser Alpha Gen IIs (transom assembly to skeg).

Just gotta figure out what I'm doing with my engines. I like their simplicity and they seem to be quite reliable. Plan for the boat is Gulf/Bahama boat so reliability is key.

Bertram26 said:

​Its a 1977 Bertram with twin GM 250s (inline 6s). I'm replacing the out drives with Mercruiser Alpha Gen IIs (transom assembly to skeg).

Just gotta figure out what I'm doing with my engines. I like their simplicity and they seem to be quite reliable. Plan for the boat is Gulf/Bahama boat so reliability is key.

Click to expand...

The GM 250 cu in inline 6 was a good engine.

I have no experience with S&J. Their website shows this:

[h=3]Specifications[/h] The above red text is incorrect.
A standard rotation engine will rotate CCW (rotation is always viewed from the flywheel end).




Have you looked here at MarineEngine dot com for this engine?

Have you looked at what MichiganMotorz has to offer?

https://www.michiganmotorz.com/inline-base-marine-engine-1963-p-546.html



.

I also have no first hand experience but If you google it there were a few hate mail posts up there.

I personally had a very good experience with Michigan Motorz on a new partial engine package. Not only were they responsive during the sale in terms of customizing the package but after sales support was also good with supplying an item that was missed in shipment (dipstick/tube), but also in answering tech questions I had.

Unfortunately due to the age of these engines you cannot get a new base engine from GM which takes all the guess work out of it.

I'd have the engines tested for overall health; compression test, leak down test. If they need anything (probably not) I would just give them a good going over, paint em and put right back in. These engines are extremely reliable, smooth, have excellent power and torque, and the parts for them are cheap as chips as they say.
If you're super super worried, have someone pull the pans and heads off, check all the guts and do a valve job on the heads.
The term "bullet proof" gets tossed around a lot but in the case of these straight sixes, it is absolutely right on.
If you change to, say, a pair of V8s, then you are going to have to modify a lot more. Up to you.