Just curious if anyone has used one of these. Thinking of adding one to a 500hp 454. What would I honestly get out of it? 100hp? For $2500 brand new i think it is the easiest addition, but will it really make power?

You should gain right around 100hp running about 5# of boost. You will need a carb that flows at least 900cfm or so, or just go with a Dominator carb.

Well, I am already working with an 850 holley but if I neeed to upgrade then so be it. I am just trying to add a bit of power that fits under the hood and won't require going inside the engine!

So, you feel this is an ok bolt on?

I had twin 500 hp's with these blowers. Change the cam and you can make about 650hp. A few notes:

1. They make some serious noise, but some like it
2. Heat- Prob makes more heat than any other blower, enough to cause a 5mph loss on top end when fully warmed. After a short rest you get the power back, then you lose it again Add a chiller if possible, not needed
3. Upgrade to the snout type tensioner it it has the old style block mount one, otherwise you will blow through belts.
4.I ran 850 cfm Nickerson modified Holley, I would highly recomend this. He knows the setup, mine boat ran like an EFI and throttle response was electric....at all temps. Send your carb to him!
5. I highly recommend crossover cooling and the water temp sensor relocated to the front of the intake or the block. Relocating the stock thermo housing up and away causes inaccurate and eroneous readings on water temps. I lost a motor shortly after losing a sea pump impellar, the water temp never showed a rise, the oil temp did but it was too late!


If you are new to blowers you need to follow some "new" rules because things happen a lot faster with boost

Keep the distr very clean, detenation comes easier
Be very picky where you get your fuel, high octane is a must
Run marine ethanol remover
Never use last years fuel, run it near dry at the end of season

Good luck, I gained 12 mph with twins on a 36 foot boat!!!!

If you try it let us know what gains you get. I have been thinking about a power adder myself. No money for upgrades this year. Plus I have clearance issues with a blower, I would have to redesign the back seat. I have also did a little research on twin turbo.

You could/should send the carb to Nickerson and have it reworked and boost referenced.

As long as you have under about 9:0 compression, then it should work fine. You will need run 92-93 octane fuel.

Sounds like this may be more complicated than I had originally thought.

Baja- most people just throw them on and go, with no problems. I was posting my results because I had some problems, however I think you could go with a 4 lb pulley and not really have to worry.

Think of it as good, better, best. After you break enough stuff (like me) you tend to try to cover everything, however I have some friends that seem to be the luckiest boaters in the world...I go the extra mile and fail, they cob job and run for years!

I know a guy with a 174 on a 330hp cast motor running 6 lbs of boost for two years with no engien problems. I wouldn't run one day and he called me, his dist cap was the worst I have ever seen...put a new one on and good to go....for me it would have blew holes in the top of every piston!

Blowers are still the least expensive HP option for boats, hands down!

This is true for me as well. That is why I sound unsure now after some of the info I have been getting!!!

Real question is, what comp ratio are you at now, and are you running iron or aluminum heads? Keep in mind, total timing should be reduced, and you may have to upgrade your fuel system to 1/2 lines, 110GPH fuel pump. Fuel PSI gauges are a good idea also. Intercooler is nice, if not, i would run x-overs, no water stats, and run oil stats to keep oil temp up and controlled. Try to keep water temp cool, and oil temp warm enough to get rid of condensation.