496 vs 502
 

I recently bought a 38ft scarab. One of the 502s is missing. Any thoughts to look for another 502 or replace with two 496s?

Replace 502

Both are excellent motors. The closed cooling of the 496 is nice. If you plan to upgrade them go with 502 because they have forged internals.

496 is now a white elephant. As is the Ilmor V-10.

This right here.

I like the MAG 496 for the closed cooling and close to hands off boating as you can get witget i/o boat.

why is that? I’ve heard a lot of good about the 496

Buy two new 502s and ad closed cooling and your golden. Sorry, ad is on Facebook.
https://cimg6.ibsrv.net/gimg/www.off...87bc9f7d5e.png

496's are great motors if the plan is to leave them alone and boat. Zero wrong with them but if you plan to mod them it isnt the best platform is all.

Nothing wrong with 496s,tons of boats out there with them and no issues,

He just does not like the 496s,he had a 496 in his boat and switched to a 525 and since then he dogs the 496s lol

2 new 502's complete, 500hp at Reid's Automotive. 781/857-2500

As far as I know the 502 still in the boat is good. I could buy one for the one missing or go with 496s. I know 496s have alot of torque. I have a 496 in my mud truck. It runs like a scalded ape.

496's have very limited ability to upgrade and most of the parts on them cost more than 502 parts.
Exactly what engine do you currently have?? and which model/year 38 Scarab do you have??

The 502's will have just have about the same torque as Merc 496's. Is the 496 in your truck an 8100 Vortec or a 454 stroked to a 496?? They are completely different on everything.

I have an 8100 vortex in the truck. I have heard the 496 is limited on upgrades. I'm currently just leaving it all stock. Just wanting to get the boat back in the water

the boat I have is a 91 year model. It still has one 502 in it untouched but the other 502 is missing

2 500 efis in swap shop, fresh rebuilds great price, get both, sell your 502 to offset it and go boating...

The 496 is a monster and responds very well to just about anything put to it. The issue is they are getting old, parts are getting expensive. There are very few mid level speed parts. They do last a very long time and under stress. Gen 7 is awesome............but GM went to the 502.......big man speaks.
Id go to 502

cool. I'll look into that

First thing I'd do is see is how healthy the 502 in the boat is and then go from there.

This is bad info, the 496 is not a monster, it is good in stock form and from there take a lot of $ to upgrade if desired. The 502 was around way before the 496 and it is still available. 496 has cast pistons and a lot of them had cast cranks.

Monster and 496 dont go in the same sentence! Take a stock low hr 502 and 496, give them both 7.5 lbs of boost and see what happens .

yep. I guess if it's good I'll get another 502.

I have a 28' eliminator with twin 496 hos and xrs, there's something to be said about reliable stock power that does 95 on gps any day and i put 80 hrs a season on and need that. Not saying you can't do that with a 502.

Because they stopped making them. They were good engines left stock but not very strong for SC. Performance parts are getting harder to find also. Even Raylar stopped making the sheet metal intakes.

I went with the 502 based 525 after talking to a lot of people and the consensus even years ago was to lose the 496 in favor of a 502. Now, sure enough, the 496 has been discontinued and the 502 is back.

The 496 was dropped by Merc because GM stopped making the 8.1 engine ,which is what the 496 is based on,GM dropped the 8.1 because of fuel economy and replaced it with the small block 6.0, which in my opinion are just as bad in fuel economy,had nothing to do with 8.1 issues,I have been with GM for 35 years we had very very few issues,

The old 502 was a very good engine because of the internals,
the 496 is a great engine as long as you leave it stock,as far as technology goes,the 502 does not come close to the 496,

as far as your statement that the 496 has been discontinued and the 502 is back, you are wrong if you are saying this was done because the 496 had issues and the 502 did not,
and if you due some research I think you would find the new MERC 8.2 is different than the original 502,,

You can actually get brand new 496 and 496 HO through Quicksilver. Mercury is casting their own blocks and builds completely dressed new engines. I just purchased two and repowered my Sunsation 32 with them.

The 496 8.1 --- GM stopped all production Dec 31 2009 and that's why the 496 went away. Merc opinion was always that the LS engine would not last in a marine app especially in a sport boat nor have the amount torque to make anyone happy in stock form. With that said I want to back up a year or 2 from those Merc statements --- Merc actually even made statements that they were coming out with LS based engines way back in 2009 but dropped all that. I know I have the memos.
The NEW Mercruiser 8.2 L catalyst engine is not anything from GM period. The block itself is Merc design but made here at a foundry in the USA. Like I said the 2010 to current 8.2 Mercruiser DOES NOT HAVE ONE GM part installed. I know cause I had this engine torn down to the very last rod bolt not once not twice but a handful of times. And the same with the 496 torn down but at least 100 times since around 2002 - (The 496 came out for year model 2001).


IMO I would take the Gen IV big block and go to town with that. Even take a 454 GEN IV --- bore and stoke it to a 496 before buying and trying to hop up a 496. I am not a fan of hot rodding a 496. Way back in the past we had groves coming in wanting more power and speed for their 496. After about a year of this and that - I changed my mind about any changes to the stock 496's. I did not want to be married to that boat owner cause most of the time nothing was gained and or the reliability was completely taken away from the marine 496 's. Keep in mind Mercruiser was not the only one doing 496's in marine trim. I seen and worked on all the marine manu s who marinized 496 's including the exclusive GM 496. I will say around 2006 / 2007 many boats had 496 s including many production boats - even Sea Rays - Cobalts - crownlines -

Raylar stopped with some parts because those parts were not selling in any form of volumes. The 496 is really good at low end and mid range but top end not as strong. IMO weak.

They are Dart Gen VII blocks. Merc does not cast the 8.1 but they do sub out the 4.5 L and the 6.2 L and the 8.2 L to a USA foundry for their own design

BUP, did Merc make any improvements on the GM design when they went in house?

The current 8.2 L from Merc is really nothing special. Internally nothing special either. The first 5 years of Merc 8.2 engine there was some issues.. And of course the GEN 3 cool fuel was used that created a lot fuel related issues as well. 3 cats in each exhaust manifold for a total of 6 did not help matters either. That was for 2010 thru very early 2014 models. .Keep in mind this is Merc exclusive 8.2 designed block and engine set up and zero GM parts. The block is Not GM either for this current 8.2. Merc does not even call it a 502 when talking about it.

Going back to the 8.1 --- the Dart 8.1 Gen VII block offers some improved upon compared to the GM 8.1 Block. If I recall correctly 2 others or maybe its one other makes the 496 block -- I do know for fact Dart and what to say Merlin or something with Bill Mitchel making 496 blocks. Dart 4 sure thou and there is one other if not 2 others making 496 blocks.

The very first 496 s HO did have a forged crank back in 2001.. But that was very limited runs for 2001. And again it was only the HO versions of the 496... . Also I seen 2 early GM - 496 blocks crack in front of the motor mount area as it has been said a few were weak in that area. If I recall there were other people that mentioned the same thing about that issue and it might have been up here years ago.

Keep in mind Mercruiser is the only marine OEM doing Big blocks no other marine engine manu is using big blocks period nor even selling repowers for their past engine line ups. except Merc.
Volvo Penta you can get a repower 496 for their past engines.

But dependable in stock form? I loved mine while I had it, as reliable as you could get, every time I stepped in the boat I went BOATING. I never modded it, if I was intending on doing that I'd have never bought it in the first place, they make engines specific for that.

Stock 496 HO ......=Great Motor, Turn Key, 1000 hrs. Very Low Maintenance. Go Boating.....Not designed for upgrades.
Only thing that I have seen is a better tune that cleared up transom soot from running a little fat. Mercruiser has always done that from the factory because of gas quality throughout the world. Better to be fat then lean.


If you want to tinker around, modify, make more power, add superchargers eventually then by all means, the 502 is the better platform.

Stop putting words in my mouth please. I said the 496 was a good engine but it is no longer being made so Mercury went back to the 502 crate engines.

BUP says they are making the new 502 in house. I don't know. I thought they were buying short blocks from GM but in any case the 496 is now a white elephant as is the Ilmor V-10. The 502 is still very relevant.

Here is some info on the 496 Quicksilver repower.


https://www.quicksilver-products.com...vo-sterndrive/

Putting words in your mouth, LOL

for the 8.1 like I said is a Dart Block and that's the big difference for improvements. For one its a stronger block and with any Dart blocks -- Dart always tries to improve upon any oiling within the block itself. Every Dart block they have made - Dart puts that statement on them - " improved oiling "

Mercruiser for the inboard and I/O side only has 3 engines and that is done 6 different ways. the 4.5 L and the 6.2 L and the 8.2 L --- again these are Merc blocks that are made at a foundry in the USA. I actually met and talked to the foundry years ago plus seen the blocks in person.

ALSO MERC is NOT using GM parts period for any of this and ALL IS ASSEMBLED IN HOUSE AT MERC.

Merc for the outboards makes a ton inhouse that is all theirs and there is no aftermarket parts for a lot of their current outboard engines. They are doing this because parts are becoming a big money maker for these marine OEM s. Keep in mind the past marine engines inboard and I/O were basically a GM truck engine and many parts could be bought at auto stores. NOT anymore - its all planned this way from here on out.

And IMO being in this industry for 31 years coming upon 32 years in March 2020 - In totally stock form the 1991 / 1992 carbed 454 was prob the most reliable marine engine built for big blocks and the small block 350 HO mag with a carb 1994 thru 1997.

I seen the early 454 engines overheated so bad and I mean really bad --- thought 4 sure they were done - nope they still ran well years and years after wards. Most of those engine outlasted the boat. Keep In mind I am located inland and talking about NON saltwater apps here.

I'd go with the new 502 can't beat new!FWC 496 very nice but go whats in the boat now! Good luck & New Year!

Those two engines in significant volume spent years being abused in cars, trucks and motorhomes before boat owners got their hands on them.

I'm thinking about keeping the boat original with the 502s. Since it has one still there. Just missing the one. Although I have no issues with the stock 8.1 in my mud truck. It's running 54 inch boggers with rockwell axles and breaks the tires loose. May be a bit different from the marine app.