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Cuda
08-30-2005, 03:28 PM
Which is faster in a 22C?

txtaz
08-30-2005, 03:39 PM
Wouldn't they be very close?
Wes

Cuda
08-30-2005, 04:24 PM
That's what I'm thinking, but I want some real world experience. Stock set ups.

MOP
08-30-2005, 05:02 PM
Now I may be speaking out of my you know whatsis and did not get all the facts I was 1/2 listening to a conversation at the machine shop about the 502 vs 496. The general drift was the 496 is much improved over the 502. I know some of the guys in the know will jump in and help this one along.

Phil

blackhawk
08-30-2005, 05:13 PM
I've heard some people say they like the 502 better and some the 496. But, most people still like the 502 better for modding.

But I would think the faster boat, stock vs. stock, will be the boat set up better and the better driver. 5-10 hp is a very small difference.

ChromeGorilla
08-30-2005, 05:32 PM
The HP is practically identical. If you have an underachieving 496 you may have same or less HP. That said. The electronics and protection features on the 496 are awfull nice to have. To me this is very appealing. As far as hopping up..... 502 seems a better candidate to me.

Cuda
08-30-2005, 05:38 PM
The last thing I would do is modify the engine, so available mods are of no concern to me. There is much to be said for running a little slower ALL the time, than running a little faster SOME of the time. :)

Pismo
08-30-2005, 06:01 PM
An early 496 that still had forged internals sounds good.

ChromeGorilla
08-30-2005, 06:12 PM
If it's staying stock I would take a newer 496 over and older one. When the 496 first came out they came with Bravo 1's standard. Now they have Bravo X.

fasttrucker
08-30-2005, 06:26 PM
The 496 has had some problems when adding a whipple blower. :kaioken: One guy here went 60 hours before the twin engine set up blew.both motors.But the 496 has the freshwater/rad. thing going for it.Stock 502-415hp.Stock 496-425hp

blackhawk
08-30-2005, 06:39 PM
The last thing I would do is modify the engine, so available mods are of no concern to me. There is much to be said for running a little slower ALL the time, than running a little faster SOME of the time. :)

Yep, I agree! That's the reason I stuck with factory power over a crate motor or "aftermarket" motor when I re-powered. I like having peace of mind! :yes: :D

blackhawk
08-30-2005, 06:42 PM
An early 496 that still had forged internals sounds good.

I thought the higher hp(HO and GXi motors) had forged internals?

joseph m. hahnl
08-30-2005, 07:06 PM
[QUOTE=.Stock 502-415hp.Stock 496-425hp[/QUOTE]


i saw both motors are availible in a carrera boats.
and the 496 mpi was availible in a 375 hp to a425 hp
and the 502 was availible in a 415 hp to 475 hp wether the 502 was carbuerated was unclear. so to me it sounds as if the 502 has more hp than the 496.
but what exactly makes it a 502 cid ? is it stroke or bore? is a 502 a remanufactured 496?

joe

Carl C
08-30-2005, 07:17 PM
I think the 502 is a larger bore, shorter srroke motor. That has always meant more RPM and more HP to me. Does anyone know the bore and stroke of these motors?:boggled:

blackhawk
08-30-2005, 08:47 PM
496 has a 4.25 x 4.38 bore and stroke. 502 has a 4.47 x 4.00 bore and stroke.

The 496 is offered in a 375 hp package and a 425. The 502 mag was offered at 415 hp since the MPI came out(1994-1995?) The 470 hp 502 is a HP500 motor which is a blue motor(merc racing) and a totally different animal as is the new 525.

Cuda
08-30-2005, 09:04 PM
Aren't the 502 and the 496 based on two different blocks?

blackhawk
08-30-2005, 09:13 PM
Aren't the 502 and the 496 based on two different blocks?

Yes, different bores.

Cuda
08-30-2005, 10:45 PM
Yes, different bores.
I believe it's more than that. I don't think anything from the 502 will work on a 496.

blackhawk
08-30-2005, 10:50 PM
I believe it's more than that. I don't think anything from the 502 will work on a 496.

I don't know about that. I was just stating that they are different bores and therefore two different blocks.

Cuda
08-31-2005, 06:17 AM
Different bores doesn't necesarrally mean different blocks, for instance, in sbc, the 265, 283, 302, 327, 350, and 383 are all based on the same block. Some of them have the same bore.

mrfixxall
08-31-2005, 01:50 PM
a 496 has a 4.250 stroke and a 4.380 boar a 502 has a 4.00 stroke which is the same as a 454 and the 502 has a 4.500 boar ... a 496 will take longer to build power with the longer stroke a 502 will give you quicker power with the shorter stroke which is better for a boat so the answer to your question is a 502 would be better for all around performance..

Pismo
08-31-2005, 01:59 PM
The newer 496's have cast pistons. The 496 is a stroked 454, by 3/8". The 502 is bigger bore 4.25 vs 4.467 and when stroked 1/4" over and bored to 4.50 it becomes the infamous 540 and can be done with a standard deck stock block so as not to screw up you exhaust hole placement. The Merc HP525 and 600 are based on the 502 block with all forged internals. The HP850 and HP1075 are also based on the 502 block bored to 4.5 and stroked to 4.375 tall deck block with twin screw Lysholms on both, therefore huge HP. There is very little difference in the HP and torque curves of similar cubic inch motors with different bore and stroke ratios (see July Hot Rod mag article) Long stroke, small bore ~500ci motors vs short stroke, big bore ~500ci motors makes little to no difference in the HP/torque curves in these larger cubic inch motors. Total cubes is all that counts.

CHACHI
08-31-2005, 02:10 PM
The newer 496's have cast pistons. The 496 is a stroked 454, by 3/8". The 502 is bigger bore 4.25 vs 4.467 and when stroked 1/4" over and bored to 4.50 it becomes the infamous 540 and can be done with a standard deck stock block so as not to screw up you exhaust hole placement. The Merc HP525 and 600 are based on the 502 block with all forged internals. The HP850 and HP1075 are also based on the 502 block bored to 4.5 and stroked to 4.375 tall deck block with twin screw Lysholms on both, therefore huge HP. There is very little difference in the HP and torque curves of similar cubic inch motors with different bore and stroke ratios (see July Hot Rod mag article) Long stroke, small bore ~500ci motors vs short stroke, big bore ~500ci motors makes little to no difference in the HP/torque curves in these larger cubic inch motors. Total cubes is all that counts.When did GM/MERCURY go to cast pistons in the 496? Is the crank also cast? Ken

Pismo
08-31-2005, 02:12 PM
Back to the original question, the two motors are so similar in power that other factors will make a bigger difference in top speed than the motors, like mufflers, prop, etc. A dialed in 496 will beat a 502 and a dialed in 502 will beat a 496. Other factors like the distributorless ignition, stock closed cooling, and standard X drive on the 496HO are nice but if adding a whipple, the 502 will probably hold up better. The 502s are usually slightly lower compression 8.75 vs 9.1.

Pismo
08-31-2005, 02:21 PM
The 496 has a cast iron nodular crank and cast hypereutectic/aluminum pistons the change was made on late 2001/early 2002. Rods are forged still.

blackhawk
08-31-2005, 02:39 PM
Different bores doesn't necesarrally mean different blocks, for instance, in sbc, the 265, 283, 302, 327, 350, and 383 are all based on the same block. Some of them have the same bore.

I guess you're talking about external bolt ons in that case I have no idea. "Based" is the key word here. To me different bores=different blocks even if they are externally the same.

Like I said before the faster boat will be the one set up the best, period. 10 hp is a VERY small margin! IMO you can't go wrong with either one. :D

rayjay
09-01-2005, 05:58 PM
The real big difference is the heads. The 502 uses older style BBC heads where two intakes are next to one another with two pairs per side, and the 496 uses a new head with separated intakes and exhausts, like most FORD's. Supposed to fix some of the flow difference problems to individual cylinders caused by the pairing. Remember the short/tall FI stacks run on the BBC McLaren's and other CanAm cars. Those were to even out the flow, not tune cylinders to different RPM range as a lot of people think. Also has the 502 intake has a "rectagle" or "oval" cross section shape while the 496 has a more modern tall thin shape. Chevy calls them "Vortecs" as they are supposed to promote velocity over pure cfm flow. Time will tell...

rayjay

bob haver
09-03-2005, 06:30 AM
Which is faster in a 22C? I think both engines are excellent engines, but I have beaten many 496 HO's with my stock 502. It could be contributed to the guidance I received from Ron at Merc Racing on the prop that he suggested for my boat. My boat is a solid 74-76 mph depending on the water conditions. "I would always stick with a 502 because it is a better mod motor and its bullet proof." It really all depends on how your boat is dialed in.
That's my two cents!
Bob Haver

Pismo
09-03-2005, 12:27 PM
Bob,

What prop did you finally settle on? I have a solid 74-76mph 502 as well using a labbed 27" Mirage Plus. I bet you have no mufflers, most of the 496s I see have permanent mufflers mounted in the tailpipes. This is costing a few mph on the boat. I don't know why they are so popular, they are totally unnecessary on a switchable exhaust boat, which most also have.

blueliner
09-03-2005, 01:40 PM
not to sound stupid, but by muffler do you mean a switchable silent choice system. i have the quick and quiet plus 2 system on my classic. is this"muffler" part of this sytem and if so, is it easily removed. i don't want any stuff on this boat that is not absolutely required. i want to whipple her when the warranty expires, but until then i will take ever mph i can get.
Bob,

What prop did you finally settle on? I have a solid 74-76mph 502 as well using a labbed 27" Mirage Plus. I bet you have no mufflers, most of the 496s I see have permanent mufflers mounted in the tailpipes. This is costing a few mph on the boat. I don't know why they are so popular, they are totally unnecessary on a switchable exhaust boat, which most also have.

knots2u
09-04-2005, 10:41 AM
Out of the crate carburated 502ci. 502hp @ 5200rpm, 560 ft lb torque @ 4200rpm. Fuel injected version is 539hp @ 5100, 572 ft lb @ 4000.

Pismo
09-04-2005, 11:50 AM
No, in addition to the switchable exhaust are frequently tailpipes that have mufflers built into them, they are not needed if you have switchable exhaust. So you open up the exhaust to thru transom and it still goes thru these mufflers in the tailpipe eating up hp and mph.

blueliner
09-04-2005, 01:27 PM
i have the corsa captain call exhaust system, which i guess is what donzi installs on all of their boats. i went to the corsa website and they boast about increased performance and hp w/ their system. how would i know whether or not mine has a muffler in the tailpipe???
No, in addition to the switchable exhaust are frequently tailpipes that have mufflers built into them, they are not needed if you have switchable exhaust. So you open up the exhaust to thru transom and it still goes thru these mufflers in the tailpipe eating up hp and mph.

ChromeGorilla
09-04-2005, 02:31 PM
Blueliner....I would bet that your boat has Corsa tips, which yes do muffle the exhaust. They look like large cans. Should be about 6" in diameter. I have a 496HO without switchable exhaust. I have straight exhaust with no mufflers. Here is a picture of what my tips look like.

ChromeGorilla
09-04-2005, 02:36 PM
These are the Corsa exhaust tips (people call'em "cans") that we are duscussing. I would guess that these are the same as on your boat blueliner. Yes they are a muffled tip.

http://www.donzi.net/forums/attachment.php?attachmentid=9204

bob haver
09-04-2005, 03:05 PM
Bob,

What prop did you finally settle on? I have a solid 74-76mph 502 as well using a labbed 27" Mirage Plus. I bet you have no mufflers, most of the 496s I see have permanent mufflers mounted in the tailpipes. This is costing a few mph on the boat. I don't know why they are so popular, they are totally unnecessary on a switchable exhaust boat, which most also have.
Yes, the same exhaust system, its a lab 26 4 blade prop. I have sent it back to Merc racing, it picked up 200 rpm. I am running 5050 rpms, no chine walk. I have another bravo 1, 26 inch pitch 4 blade labbed prop, brand new in the box with hub kit. I hope to see you in lake george this week-end at the barbeque.
Bob

blueliner
09-04-2005, 03:28 PM
is there a way to remove the "muffle" on the inside w/o altering the appearance on the outside?? i like the look of the "cans" but don't want to sacrifice performance. sound is not really an issue where i am at, so i'm not really concerned about it.
These are the Corsa exhaust tips (people call'em "cans") that we are duscussing. I would guess that these are the same as on your boat blueliner. Yes they are a muffled tip.

http://www.donzi.net/forums/attachment.php?attachmentid=9204

ChromeGorilla
09-04-2005, 03:57 PM
I don't know. I never had the cans and have never seen the internals....

blueliner
09-04-2005, 04:02 PM
does anyone have any info as to what chrome and i have been talking about???
is there a way to remove the "muffle" on the inside w/o altering the appearance on the outside?? i like the look of the "cans" but don't want to sacrifice performance. sound is not really an issue where i am at, so i'm not really concerned about it.

RedDog
09-04-2005, 04:21 PM
does anyone have any info as to what chrome and i have been talking about???
Do a search - its been discussed before. I think it involves drilling out the rivets / studes that hold the baffle. Not sure if the tip has to be removed first to do this. The consenous was it would be best to just replace the tips with a set of straight through tips. Corsa does make a straight through "can" style tip but I think they are pricey. Best ticket would be to get some standard straight or slash tips from Stainless Marine or other supplier.

PS - I have the muffled "cans"

Pismo
09-04-2005, 07:29 PM
Bob,
Is it a hydromotive 4 blade? My boat is very unstable with a 27" lab MPlus, it never settles in, too much paddle wheel I have read in the MPlus 27". It handles better with a 25" regular Mplus which is what I use most of the time. I have yet to try a 4 blade, but I would like to, I have access to a 26" labbed Bravo I 4 blade. I also porpoise a great deal at speeds below 3500rpm. So I am still trying props to deal with these issues.

Thanks

Pismo
09-04-2005, 07:31 PM
Knots,

I am very curious about how well your new 502/502 is doing. It looks great. That is an automotive engine I believe. Did you do any mods to put it in the boat? How does it plane and do on top? What props have you tried? What is the cam? I would love to hear any input on your performance and/or setup.

Thanks,SL

bob haver
09-05-2005, 07:59 AM
Bob,
Is it a hydromotive 4 blade? My boat is very unstable with a 27" lab MPlus, it never settles in, too much paddle wheel I have read in the MPlus 27". It handles better with a 25" regular Mplus which is what I use most of the time. I have yet to try a 4 blade, but I would like to, I have access to a 26" labbed Bravo I 4 blade. I also porpoise a great deal at speeds below 3500rpm. So I am still trying props to deal with these issues.

Thanks
Hi Pismo,

I am running a Bravo 1, labbed finished 26 pitch, 4 blade. I am running 5050 rpms. When I first received the prop, the boat ran at 4750 about 73 to 74 mph. I sent it back to Merc and gained 300 rpms. I am just on top of the rev limitor now. If you are a lake george next weekend, I will be glad to take my prop off for you to try it, If not give me a call 858-0052 or 355-7689.

Bob

knots2u
09-05-2005, 03:26 PM
Pismo,
This boat (1994 22 classic) & engine belongs to a friend. It is a marine engine, not automotive, specifically an X-Motor from Marine Power (http://www.marinepowerusa.com), go to the website then click on performance engines. No issues with the installation, dropped right in, the Gil exhaust was from the original 454 engine. He did have to replace the drive dampener, which was also from the 454. Have tried a couple different props, Mirage Plus 23 x 15.25 & 25 x 14.75, pretty much same results, low 70's GPS, I think it needs a 27 or 29 pitch. Most use is not WOT & on fairly smooth fresh water. Last time we spoke he said the boat is for sale locally, $25900 or b/o, includes a trailer. Boat is in excellent shape!



Bob
Bilt-Rite Uph.

harbormaster
09-06-2005, 09:00 AM
It is interesting to note that 496 exhaust manifolds bolt up to Gen IV 502 heads

Dregsz
09-06-2005, 11:05 PM
a 496 will take longer to build power with the longer stroke a 502 will give you quicker power with the shorter stroke which is better for a boat so the answer to your question is a 502 would be better for all around performance..

I think that is backward, the longer stroke has more torque on the bottom end and it is torque that moves boats. a shorter stroke makes more HP but further up in the rpm band so it whill rev higher at the top but be slower off the line

blackhawk
09-07-2005, 08:49 AM
I think that is backward, the longer stroke has more torque on the bottom end and it is torque that moves boats. a shorter stroke makes more HP but further up in the rpm band so it whill rev higher at the top but be slower off the line

Honestly these two motors are going to have similar hp and tq curves. They are rated within 10hp of each other and have the same rpm operating range.

Pismo
09-07-2005, 08:01 PM
Blackhawk is right, stroke vs bore ratios don't change the hp or torque curves much if any in these size engines, cubes is all that matters (see Hot Rod Mag July 05, great test of similar ci enigines with very different bore and stroke layouts--result-> tq/hp curves identical)

bob haver
09-07-2005, 08:29 PM
so cuda witch is it the 502 or 496