Why is the Gen 7 496 such a bad platform to build
10-30-2015, 11:46 AM
#131
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Location: Crystal Lake, IL
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One is perfect, never been opened and had no issues with it. The other had a some fluctuation in crankcase vacuum, I didn't discover it until I was winterizing last year. Planned on pulling both and rebuilding with a Raylar rotating assembly, but ran across a deal on replacement long blocks with a (2) year warranty so hit the easy button. even though both blocks are literally feet away from me in the shop, I haven't pulled the heads yet to see if there was an issue there (didn't see anything in the exhaust manifolds or the oil pan). Hopefully I didn't go through this exercise for nothing...lol
10-31-2015, 01:39 PM
#132
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iTrader: (9)
Who is the guy that was at he Buffalo Poker Run this year with a 26 ft Sonic - Merc 496 with a Whipple set up and completely different fuel system installed with an Aeromotive 1000 fuel pump and PCM recal by Whipple ? His set up looked to be very well put together by whomever. I do no not know who built it either.
I looked at it but do not know what internals were changed out from the engine side of things. He really liked the package and it was reliable for him. I would have to say whoever did the set up in his boat really did a nice job. Forget what hp and torque numbers were. Maybe he can give out all the details. Seen the boat running as well looked to be strong on the power side.
I looked at it but do not know what internals were changed out from the engine side of things. He really liked the package and it was reliable for him. I would have to say whoever did the set up in his boat really did a nice job. Forget what hp and torque numbers were. Maybe he can give out all the details. Seen the boat running as well looked to be strong on the power side.
Last edited by BUP; 10-31-2015 at 01:41 PM.
10-31-2015, 03:48 PM
#133
The whipple setup is a really nice kit and comes with a high flow fuel system included (Aeromotive marine pump, regulator, fuel cooler and high flow fuel filter) along with new fuel line kit and high flow (63 lb/hr) fuel injectors). I may someday down the road go with this kit after I do the bottom end as well. Should put me around 800 horsepower. I may never get there with this boat but you never know.
11-01-2015, 01:28 PM
#134
I spent a little bit of time today dialing in the idle a bit now that I have my Rinda scanner (thanks BUP). Set the TPS via the idle stop screw to .71 volts on the Accufab (as low as it would go and the throttle blade was hooking the bore a bit) , started the motor and still had an IAC duty cycle of 100%. Took the throttle body off and drilled the hole from 1/4" to 9/32", reinstalled and found IAC down to 65-70%. Took the throttle body off again and increased the hole to 5/16" and reinstalled. Now I have IAC counts at about 20-30%. I didn't like the feel of the throttle plate fully closed so I brought the stop screw up so TPS is about .76 volts. The throttle plate off idle feel is much improved, IAC is down to 10-20% which eliminates almost all of the IAC hiss, and with the IAC hole in the throttle body closed with my finger the idle is right at 600 rpm. I'm going to leave it right there and see how it does once it is back in the boat but I am happy with it.
I also modded my factory flame arrestor so it would fit over the throttle body. I sort of hate it. It fits, but I don't like how it looks, kinda hack to me. Nobody other than myself will ever see it but it really irritates me, maybe I will be able to find some sort of better solution over the winter. At this point this motor is done, ready to go back in the boat and get going on the next motor. It will probably be 2-3 weeks before I see parts for that motor.
I also modded my factory flame arrestor so it would fit over the throttle body. I sort of hate it. It fits, but I don't like how it looks, kinda hack to me. Nobody other than myself will ever see it but it really irritates me, maybe I will be able to find some sort of better solution over the winter. At this point this motor is done, ready to go back in the boat and get going on the next motor. It will probably be 2-3 weeks before I see parts for that motor.
11-01-2015, 01:47 PM
#135
Banned
iTrader: (9)
Matt your welcome and I am so glad that you got it in your hands. 100 % IAC duty cycle at idle is one sure way of going thru IAC's in short order. Stock Merc 496 usually run at 25 to 35 % duty cycle and still hiss like cat. Just saying.
Good luck with your build.
Good luck with your build.
11-01-2015, 02:08 PM
#137
Right around 650. I am assuming with IAC count varying that is very close to where the ECM is targeting idle. One thing I find interesting is that the gear position indicator is always saying the engine is in gear, even if I jumper the connector. I believe the out of gear idle RPM is supposed to be 600 while in gear is supposed to be 650.
11-01-2015, 04:07 PM
#139
The bracket and switch are still in the boat, I just jumpered the plug on the engine harness. I was assuming it is a simple open or closed switch. It has never been an issue in the past so I doubt it is an issue now. I will compare it to the other motor when I have that running on the floor.
11-08-2015, 06:44 PM
#140
So I have shipping notifications for my second kit on the way. I should have all my parts Friday of this week for the next motor. I have been doing some thinking and it seems kind of silly to enhance the intake, cam, and heads, but leave the stock exhaust so I decided to order Dana Powerflow exhaust for both motors. I went with the larger 3.5" risers and the extended length since I don't have silent choice to worry about. Another option Bob thought I would need is shaving a bit from the mounting surface of both inboard manifolds. It isn't much he is taking off, but he recommended it to make fitment in the boat a little easier. I also went with the hard anodizing and powdercoated the manifolds gloss black. He had all the parts in stock so hopefully the machining and powdercoating won't take too long and they will ship soon. I am pretty excited about this, I think it is going to round the package out pretty well.
