KAAMA,
The bigger the motor, the less stress it takes to make a given power. That said, a 502 would be great but, at 700hp, not necessary for a dead reliable engine and the smaller displacement would give better fuel ecenomy. Again, CAM and HEADS are critical, no matter what. Aluminum heads of almost any kind are better than almost any iron heads, especially when it comes to detonation prevention(the #1 killer of blower motors.
The Whipples will make up for the smaller displacement, even at low end.

Re: Whipples for 700hp/torque???...
 

I am not following the torque request?? if you make 700 Hp it seems to me you will make more than 700 ft lbs torque along the power band. My 502 x whipples produced something like 750 Ft lbs of TQ well under 5000 then it drops off at the higher RPM's

see my dyno sheets:
http://www.raymondbaldwin.com/WhippleInstall/dyno.pdf
(about 300k)

Raypanic - thanks for the report on your project. Keep that data coming!

Given the forged bottom end of the HP500EFI engines, along with them making your HP and Torque requirements without extra components and high boost, I would believe this to be the most reliable of the combinations. Give Dustin "Whipple Charged" a PM and see what he says. There was a thread about reliablilty of the HP500EFI and were a few posts from people with Whipples running reliably with something like 300 hours. I'll be looking to Whipple myself but am still under warranty and can't bring myself to give that up. That and the $7K per motor ;)

Steve

Mark what thr heck are you talking about?????you are the naturally asperated big cube King!!!can I have the 540's I'm a real nice guy and promise to be nice to them!!!!Its almost Christmas .......

Ray,
What do youhave planned for the 502's in the 38? Weren't those just built up this past winter?

Mark/KAAMA,
Consider giving Steve David a PM. He's got a few Whipple charged HP500 EFI's and says the output is between 680 and 700 hp.

-Bayley

Bayley,

I believe I will be selling the PQ, Not sure yet though. I bought a 47 Fountain (less engines) and am having Tyler build up the engines for it. These will be the 540's. I had a couple of 502's from the PQ after the re-power last year, I am using these for the fountain. When it is all said and done I can have the 540 x whipple packages for a little more $$ than Merc 525's. (+200 Hp) Because of all the parts I have from the last re-power I am saving a lot of $$$. I have full confidence in the whipple products and Tylers' abilities so I figured why not? I plan on doing alot of the work myself to save some money too. Lets see if I can break 100 :eek:

Raypanic, so that was a "roots" style vs. centrifugal (did I spell that right?) supercharger in the picture you posted? I thought all Whipples were manufactured as a centrifugal type. Thanks for all the input you guys.

And yes, I want to keep the torque at right around 700 foot pounds between 3000-5500rpm. HP can be 700-720hp or so. I would probably prefer the carbed version. Also looking at 871 Littlefield with 2x4 750cfm Holley's.

Dyno, if I do this I would sell my rotating assemblies, intakes, 950 carbs, heads would be for sale too,----not going to give it away, but I usually try to price things to sell. I may not even do this---I'm just checking it all out and I'm very interested.

Kamma, if you want, shoot me an email regarding some of the particulars, such as what engines you currently have or if this is a new boat and starting from scratch, approx. budget, etc.

Ideally, the cubic inches are a lot of help, and if your starting from scratch buying a crank, rods, etc. than a 540 is a very logical choice, but if your starting with something else, there are other venues. I would include aluminum heads, thats for sure. I can tell you a good head and cam choice that will certainly make the power. Paul Phaff and Gary Teague are both building packages like this in EFI. Tyler Crockett is close to you and I can work with him if needed to achieve this. With this level, we can do everything with the MEFI 3 ECU and I can email files to Tyler if needed. I can send something really close that will only need to be fine tuned in the boat or on the dyno. They will idle, with no surge, no problems there :D

This is a pretty simple task, so EFI will have the best idle and most consistent turn key operation, but carbs are hard to beat, once there dialed in, there pretty darn reliable. So let me know what your starting with and I can share some info if needed.

To answer your power questions:
454 Mag SC'd
590-610 HP/660-700lbs. of torque w/stock heads
675-700 HP/700-730lbs. of torque w/aluminum heads/cam change

502 Mag SC'd
620-640 HP/710-740lbs. of torque w/stock heads
700/725 HP/730-775lbs. of torque w/aluminum heads/cam change

500 HP EFI SC'd
690-720 HP/775-820lbs. of torque w/stock heads
750-800 HP/800-850lbs. of torque w/aluminum head/cam change

These are all with the new "top mount" systems.

At the same time, the aluminum headed motor will be more consistent in power, more reliable in terms of detonation as well as fuel and water psi variance.

Thanks,
Dustin