good to hear you found a motor. where did you end up finding one?
I just picked up a 454 MAG MPI 385hp with 20 hours on it for a great price, a good bulletproof motor, it needs a fuel system including the intake. So I am calling Whipple today to see if their 7.4 MPI 310hp system will sit ontop of the 385hp MAG, I think it will!
Has anyone do this?
KC
good to hear you found a motor. where did you end up finding one?
THOR,
KC, you sneaky bastard. That is the motor I have and it runs great. I too would love to see what a whipple or ProCharger would do. Have you checked both? A friend of mine has the 7.4 and put a PC on it for a gain from 64-74 mph. Sweet
I have been on the phone with Whipple all day....
On the Whipple website is a photo of the 7.4 MPI 310hp kit that they sell, or used to sell. Unfortunatly the 310hp motor components are not strong enought for the extra power so Wipple suggests replacing the pistons and rods. That equates to pulling the motor and fitting new pistons, a 2 bolt mains motor at that.
Whipple also offers a kit for a 454/502 Mag MPI, it bolts onto the side of the motor and uses the Mercruiser Injectors with a remapped ECU.
It sounds like Whipple is phasing out the side mount kit, in favor of the top mounted kit as shown in the 7.4 MPI photos. The kit comes with an intake manifold, intercooler, 2000cfm throttle body, injectors, re-map of your MEFI 3 ECU, all small goodies including pulleys and belts - and a day of calibrations on the ECU on their local lake.
This makes for a very clean implementation of 615hp on my recently acquired 454 Mag, over 700hp on a 502 Mag.
I snagged the motor off of EBay, a complete long block with 20 hours on it less the intake and fuel system, I hope it is as clean as the guy says. This guy built a 540 motor and placed the MPI from the 454 onto the 540 with $1400 worth of ECU mapping.
My game plan is to unbolt my accessories from my 310hp motor, take the boat to my service shop so they can crane out/in the two motors. Then bolt the Whipple kit and all of my accessories onto the new motor. Finally tow the boat from Havasu to Whipple in Fresno so that they can do the calibrations on the ECU. I hope to accomplish all of that over the Christmas Holiday shut down at work.
Currently I have the Stainless Marine headers and risers to help this monster exhail.
The next questions are... do I need a Bravo I 26p or 28p.... gear ratios?
Nice thing is I have lots of time for research.
Too bad Whipple does not offer zero percent down and zero percent interest!
KC
kc, you will need a 28p bravo 1 prop. it is rally a 26.5 when comp. to other props. i have around 600hp now and run that prop. it is grat. i may even be selling it due to the fact that my new 540 procharged motor should run 800hp-850hp. i will let you know if i put it up for sale. good luck with the new motor.
502procharge....
Thanks, I'll be calling the propeller company in the AM to get their read on the prop and the gearing.... sounds like I need to have the prop stepped up before whipple tunes the ecu.
This is fun! KC
i guess i need to look at the screan when i type, i look like a retard with all of the spelling mistakes.
KC,
My buddy that did the same thing is running a 28P on his 22' boat. But, that is a smaller rig than yours. I would run an 26P or maybe a 27P mach if you can find one. I doubt you would want to push that motor to its limits for an extended period of time.
Thanks guys!
Yes, I would prefer acceleration over top speed, so a 26P might be the ticket for the Whipple.
Still working out ideas on this motor, the Whipple is big bucks and I just don't want to dive into the deep end so fast. Good and bad, is that my new motor is basically a long block, so no fuel system but it does have the MPI cam. If I can find an MPI system then I have a sweet low budget motor, but if the MPI is spendy then I might as well apply the funds towards the Whipple.... I have plenty of time on my side.
Thanks for everyones input, KC
KC - I have a 454mag efi also. Been kicking around the same top mount whipple idea. But one step farther -- I was thinking of putting 8.0:1 flat top pistons in, the 500efi cam in, and a little head work. Then bolt on the top mount whipple and get the ecu calibrated. I'm thinking it'll make around 650-675hp and still idle nice. And at 8:1 I have the option of bumping up the boost on occassions.
If anybody's done something close to that, I'd like to hear about the results.