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desertbird
04-14-2005, 09:07 AM
Allright folks, there's a ton of discussion about upgrading the MAG HO. What about those of us that foolishly got the MAG only and now want the extra 50 horsies?
1) Is it anything more than a camshaft, a computer and a sticker on the cowel cover that will get it there? I wonder what the cost of doing that with Mercruiser parts would be compared to a Raylar or ASM kit.......
2) Regarding supercharging, I've done some research with Whipple, and the only figures they have are for the HO. Impressive. 650 HP and 636 lb-ft. with 5 lbs boost. Since Whipple re-programs the ECU, the only difference then is the cam? If all things were equal, the MAG would be 50 HP short?

jbtrailerjim
04-14-2005, 09:18 AM
I wouldn't say your foolish for buying only the Mag and not the Mag HO. I'd say you got an extra $3k or $4k in your pocket. I bought the Mag only also. Ultra actually recomended me not to spend the extra money on the HO since I would only see a few more mph out of my boat.

Beer-30
04-14-2005, 09:25 AM
I'm sure you've see the 496 HO UPGRADES which started out small and has now grown into a very informative thread. All of the same things can be applied to the MAG.
The only way you are gonna equal an HO is to tear into the motor. If you are like me, and not ready to do that, your options are limited to what is in that thread. Exhaust, maybe some fuel tweaking, and flame arrester (which is probably not a power increase itself, but cleaner air just the same). I just brought up an issue about roller rockers that may be another 20 or so horses, + or -.
I for one don't plan on going further than changing upper valvetrain, until a raylar kit is going in. Since that's a few years down the road, I will continue to tweak the stock setup with reliablity in mind.

desertbird
04-14-2005, 12:15 PM
Yeah, not foolish, thrifty. The funny part is once we saved the coin, now we'll spend that much and more on aftermarket bling-bling B.S. All for minimal gains!
I've already bought the K&N, everything I own has a K&N filter. Once I found out about the stupid exhaust Turdulators, I ordered new gaskets, and those are coming out! When I have the risers off I will take a look and see how well the ports are lined up and if there is any gasket intrusion, but after that I'm not doing anything else! If I go, it'll go big and I'll Supercharge it. For now I'm a guy that still likes reliability more than a few more MPH. I must be getting old!

Chris Winn
04-14-2005, 12:19 PM
if i would have thought in advance (i seldom do :hammerhea ) i would have bought the regular mag and had the raylar kit placed on it witht he saving (at least part of them)
one idea might be to find someone who has installed the lit and buy thier cam and have whipple do a re-flash if that will work, i am not completly sure just thinking out loud............

Dave C
04-14-2005, 01:20 PM
Isn't it Raylar's whole "angle" to get the MAG and keep the $4-5k that you would have paid retail for the HO and buy his kit and get 100 more horsies!.
thats a pretty good angle.

jbtrailerjim
04-14-2005, 04:09 PM
The only thing I would do to my engine would be the Raylar kit and that is only if I have the dough to do it. The problem I have is if I add the extra horsepower to it. Then I'll need external steering and then probably a set of trim tabs. Oh and I can't forget about the new prop. Damn, where does it end?!?! :squiggle: :eek: ;)

Chromegorilla
04-14-2005, 07:08 PM
Internals and horsepower aside the other MAJOR difference bewtween the regular 496 and the HO is the HO comes with an upgraded drive as well. the bravo X is standard as with the reg Mag you only get a Bravo 1. You'll be spending the $$ you saved buying the regular Mag vice the HO when adding raylar, whipple sc or procharger in the form of upgrading your drive. Or just use the B1 and when it shits its self (maybe not today or tommorrow , but it will) you'll definately be spending some loot then. Just another point of view.... :D

Beer-30
04-14-2005, 07:11 PM
Mine was before the X came out. I only have a B-1 behind the HO. Numerous people on the board here say it will last quite a while if respected.

Chromegorilla
04-14-2005, 07:41 PM
Your right, it will last when respected. But you know how most guys are, they want to run hard. And that one time you idling along and someone wants to run and you get on it good, it shits its self.
Also if you have a heavy boat vs a lighter boat the drive issue is more applicable I feel. A single 23' boat with a single engine with a B1 getting on plane is alot easier on the drive than a 35' boat with twins and B1's. 4K lbs vs 10k lbs. OK I'll stop rambling.....

Beer-30
04-14-2005, 09:51 PM
I'm with ya. I just 'roll' into the throttle. Most of the time fairly slowly, but sometimes I start the roll and then as its just about to start nosing over I'll put it to the stop. So far so good.

DM25CITATION
04-16-2005, 11:08 AM
iam with u guys who got the mag. i got talked into the mag because of the less 50 ponies and i didnt think it would make a differenies. plus i saved the $$$. after having the mag, i was very unhappy if the performance. i did some research and thought i had to dump $10k to get the ponies or a new motor. than a miracle happen and Raylar kit came along. now iam glad i got the mag beacuse the money i saved not going to a HO. i put it in the raylar kit. the power is night and day. my 2 cent is not to waste your time and money to work on the stock motor. just save the money until u can buy the raylar kit.
hey beer.
iam also a first time boat owner. i have a 2003 advantage 25 citation. i have put hours and hours in research for more ponies. the best is the RAYLAR KIT. 496 pistons and rods will not the handle a supercharger for the long run. i gain about 10 mph and hopefully when i dail in on a prop, i would be at 14.
go big or go home right!!!!!!!

phebus
04-16-2005, 11:22 AM
Where are you at now with your prop, and what is next?

Beer-30
04-16-2005, 02:12 PM
OH, I'm with ya, DM, I just have to wait awhile for the kit. But see, anything I do to it will be usable on the Raylar. Porting the exhaust, K&N, even if I change rockers, I can either sell them to someone else later or just put them into the Raylar.
I'm definitely not going to do anything stupid like port the stock heads or change the cam. I will just wait on that stuff till Raylar time. No fancy stuff. I just want it as efficient as it can get without a teardown, thats all.

DM25CITATION
04-16-2005, 03:33 PM
i tested a 28pitch and next will be a 26pitch. i ran 70mph @4800 to 4900. that was with a aliunium prop. i figure with a stainless steel and lab prop, i'll get a few more mph. i have more rpm so i think the 26 pitch will give me that but i dont know if i will gain mph. does anybody know if i will???

mike37
04-16-2005, 05:09 PM
I may be wrong but the HO has 4 bolt main and the mag just has 2 bolt main
and a different cam
but if you get the raylar kit for the mag will be identical except for the 4 bolt main to the ho with the raylar kit

FASTERDAMITT
04-16-2005, 10:54 PM
Injectors and cam are different. If you do a Whipple it won't matter on the injectors, thier removed. The cam will hold you back a little. Dustin says he has 496's with Whipples with 100's of hours. I don't know. Low boost, higher compression Raylars heads= same thing. Higher combustion pressures and more load on the bottom end. Take your pic!

Raylar
04-17-2005, 11:41 AM
A camshaft and the program in the ECM. Absolutly those are the only two things different between the two. There are absolutly no other differences internaly or externaly except the decals on the plastic cover. Take this as gospel from those who know.
Ray @ Raylar :cool:

Kachina26
04-17-2005, 11:44 AM
Is there anything you don't know, Ray? :D
What year did they change the crank on the HO motor?

Beer-30
04-17-2005, 12:56 PM
Allright folks, there's a ton of discussion about upgrading the MAG HO. What about those of us that foolishly got the MAG only and now want the extra 50 horsies?
Hey, DESERTBIRD. I think you and I are in the same boat (no punn intended). If you are like me, you plan to do a RayLar kit in future. But for now, you want to do as many mods as you can w/o dipping in to the funds, right? Or. Maybe you don't plan on doing a RayLar or supercharger.
So, we have both yanked the turbulators out. I plan on pulling the manifolds and risers off and porting them to match the gaskets. These will then be ready for the future kit and provide better flow right now.
The cam in a MAG has .284" exh lift, .282" int lift. X 1.7 ratio of stock rockers equals .482" / .479" valve lift - respectively.
For around $500-600, you could get the RayLar 1.8 roller rockers, the conversion studs, gaskets, and a new set of pushrods.
Now, your valve lift goes to .511 / .507. Of course, we can't change the duration. Compare that to a stock HO cam that is .300 / .300 at the cam. 1.7 stock rockers put the valve lift at .510 / .510.
So you could bring the lift of the cam up to HO specs. Plus, getting rid of the stock rocker friction and gaining the smoothness and reliability of the rollers, I'm sure you would be a little over gaining your 50 horses. The rollers could be used on RayLar heads later or move them to another big block, or sell them. I plan on putting them on my HO. Will take the lift to .540 at the valve.

phebus
04-17-2005, 01:26 PM
So, we have both yanked the turbulators out. I plan on pulling the manifolds and risers off and porting them to match the gaskets. These will then be ready for the future kit and provide better flow right now.
The area that I saw ported by Aaron at absolute was the exhaust runners where they come together at the top of the manifold. The area was very full of metal, and was choking the whole thing off. He removed a lot of the metal, thinning out each runner and leaving a much larger area where the manifold exits to the riser. The actual area the gasket is, was very close to the diameter of the riser, it was the area below.

Beer-30
04-17-2005, 02:17 PM
Yeah, I meant all areas of concern. Runners, checking the ports at the head, and the runners where they come together. Along with checking the gasket area.

desertbird
04-17-2005, 02:23 PM
Yeah Beer, I'm with you. I've been building and modifying engines since my days in high school and my Big Block El Camino. Most recently it's a bad-ass 383 in my motorhome (so I can tow the boat to Lake Mead) and the pic in my Avatar is my first Merc V-6 outboard build! (That boat is for sale right now).
Now, back to the 496 MAG. As you can imagine, it pains me to leave this engine stock! I think there are two breeds of people on this thread, and 1/2 think Raylar, half think Whipple. All of us knowing that the bottom end will be put to harder stresses with any kit, don't fool yourselves. For me, I think I'll go Whipple, it seems to be the most direct, and I have heard mostly positive things about mild supercharging.
Yep, the turbulators are on their way out, and when I have it open I am going to thouroughly check out the porting and gasket matching on this motor. This season she's gonna stay normally aspirated, but I still want as much bang as I can get.
The 1.8 ratio is the oldest trick in the book for a cheap cam upgrade. Even going "halves" with a buddy on a set of 1.7 and 1.8's to change the exhaust and intake lifts and get a "bumpier" idle. I can imagine that working on the MAG, but make sure you have clearance and valvetrain hardware (springs, etc.) to handle that much more lift on the HO cam profile. .540 is getting pretty big!
I see that Raylar offers the cast rockers. I've broken those before, but I think they are the only type that will fit under the stock cover. What about GM Performance Parts? Is any of their stuff applicable?

desertbird
04-17-2005, 02:33 PM
I'll throw another one out here today, what about Synthetic Oil? Anybody run it?

Beer-30
04-17-2005, 06:14 PM
No, nothing GM. I was considering the $280 valve cover spacers from ASM, and then just put on the Crane Golds. I am not worried about breaking cast rockers unless I threw on some ridiculous springs. I am sure the stock ones are fine for now. Yeah, I would check for coil bind but I am quite certain the valve-piston clearance is just fine.
I am a Whipple guy too. Had one on a 1995 2500 4x4 350-TBI (210HP), pre-vortec. It was a heavy truck (xcab, long bed), but with Thorley long headers, an enlarged throttle body and matched injectors, high flow cat and Edelbrock cat-back, it ran real nice.
The 496, although I have not seen one with a head off, apparently has a bad combustion chamber to cylinder relationship. I have no reason not to believe these guys that have had them apart. They say it is "choked" up and I strongly believe they know what they are talking about.
Yay though there will be (probably) some more horsepower from the Whipple application, I can't get over knowing that there is an inefficient transfer from cylinder to head. Since I know that now, it makes me want to correct it. Therefore, I figure the RayLar kit is going to be a large step up in power with other benefits. The weight savings of the aluminum heads is a plus. The efficiency of the cooler intake and better port/runner shape is another one.
So, I think my initial money will be better spent for that. This way, when the stock bottom end gets tired, I just rebuild with RayLar strong stuff, get some hours on it, and then put the whipple on after that!
I just figure the rocker idea will buy me another couple of years of easy running until I am ready for the kit.
I just changed it from whatever regular oil that they had in it, to Mobil-1 10-30. I have been running this in my 1998 7400 Vortec powered dually tow unit. I didn't really notice anything other than it is alot cleaner at change time. You can actually still see through it. It's just nice to know it's in there. I put a Fram on it for now, but I have a Mobil-1 filter for after the first load washes everything out.

mike37
04-17-2005, 08:03 PM
just got home from the lake we took the restrictors out
and I must say it help the motor seams to run up to the rev limiter a lot faster
don't get me wrong not big HP chang but the motor felt like it opened up better