496 Whipple Stage II experiences?
 

This is the PCM reprogramming with low temp thermostat. NOT the supercharger.

Key features:
• Hi-performance PCM calibration
• Low-temp thermostat
• 5450 RPM limit
• 7% - 10% power increase over stock
• Increased acceleration with increased torque output

I'm considering the 496 Mag HO stage II PCM reprogramming and wanting to learn from some of the current stage II owners satisfaction with the performance gains and realized benefits. Following is some of the questions that I had in mind but feel free to comment as you please.

1. Do you have Single or Twin engines & what size boat?
2. Do you have 496 Mag or 496 Mag HO
3. What was your Wide Open Throttle MPH increase?
4. Wide Open Throttle RPM increase?
5. Did you notice any reduction in black exhaust soot on the transom?
6. Was there a need to reprop just because of the Stage II modification? I would assume not, but thought I would ask.
7. Sound any different? With a custom tune on a LS6 Z06 engine it sounds more aggressive, just wondering if it was noticeable on the 496 tune.
8. Have you had any difficulties getting 91+ octane at Marina's, or do you always fill up on the trailer at your favorite gas station.
9. Did you notice any increase in gas efficiency?

By the way, I have the Whipple Supercharger on my 2000 Z71 5.3 truck that I installed myself and absolutely have loved it for 8 years and counting with 120k miles. I would not consider another gas truck without installing a Whipple Supercharger.

Thank you in advance

I would go with new exhaust before anything you mentioned above. Real results have been proven with the exhaust mods. Going from manifolds to a header setup.

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Well, I don't see many responses, so I'll throw out mine. I've got experience with the stage 1 on stock engines and Raylar packages. I did a stage 2 on a Raylar package. I have been able to compare 2 identical boats(side by side)with Raylar kits. One has the stage 1 and the other the stage 2 kits. The boat with the stage 2 accelerates noticably harder and runs 1 MPH faster. It does require premium fuel. I dyno'd a 496 that I installed a stage 1 kit along with minor exhaust porting and removed the turbulators. It made 410 HP at the prop, as opposed to 387 stock at the prop. Hope this info helps you out some in your decision.

Bob

Bob, please continue with the exhaust porting and stage 1 kit making 410chp. Thats the same #s you reported that the DMP Exhaust made. If I could run the stage one kit and port the factory exhaust and pickup 23chp. I would be all over it!

Thanks guys, I do plan to remove the turbulators. Bob, that is some good comparison info, programming obviously does make a improvement. There must be some more Stage II experiences??

ttt
Any one else tried the Stage II?