KCHOTBOAT

I went from a Procharger on a 7.4 running a 9 pound pulley to a mild 540 on the same boat. I lost a few miles on top end. From what I have heard nothing but good things about whipple and the support they offer.

[ 01-05-2002: Message edited by: KCHOTBOAT ]

Mike Shaak

Niuhi, Tryed to send a pic of my boat, just wondering if you got it, as I'm not very good at this computer stuff.

bobl

Niuhi, you have a pretty good base engine now. I rebuilt a 454 Mag, added good aftermarket heads, hydraulic roller, dart intake, Holley 750 and Stainless Marine manifolds. I went from 60 mph to 70+ mph on GPS...It was a Crownline..LOL. The 540 won't give you a lot more HP, it will just do it at a lower RPM and have a lot more bottom end. Don't sell your 454 Mag short.

Niuhi

Bob you may be right on. It would probably in my best interest to look into that route also. I have to say I haven't really looked at that option. I also think I can get a little more speed in my prop selection. Ive tried a few and think I've narrowed the field to on that really feels like it freed up the hull. What were the heads that you added and what cam did you use?

bobl

Nuihi, I went with a set of Merlin 310CC heads with a good bowl port. The heads were milled .040 to end up with 9.4 compression. The cam was an Ultradyne hydraulic roller with 226/234 duration @.050 and .601 lift. I had to flycut the pistons for piston to valve clearance. Had to turn the engine to 5700 RPM to get the power out of it. It's still running with over 200 hrs. on it since the rebuild. From what I've read, Jim Valako can port your GM heads to flow nearly as well as the Merlins for a lot less money.

Niuhi

Thanks Bob.

big daddy

Family & performance boat magazine just did an article on upgrading 454 mags. No blower, just intake, ecm and fuel sys. changes. They were using an EFI engine, but it may give you some things to look at.

[ 01-08-2002: Message edited by: big daddy ]

vandeano

Weiland chargers? Any good

Kanookstr

Anyone that installed a procharger or Whipple and lost low end but gained top end only has got there system set up WRONG!!!
The difference in low end whether it is a procharger or Whipple is Night and day twice as fast if not three times better than stock!!! Yes the whipple will have a little more, but so will the Procharge. I am a dealer and installed More than 30 of these units and have never experienced a bad hole shot but good top speed. If thats the case than there is a serious problem, which 9 out of 10 times it is carb/fuel set up...Alot of people think these systems work and lag like a turbo set up. they couldn't be further from the truth..Both systems are good systems. but both systems can be bad if there not set up right..
As far as customer support goes, Dustin will go out of his way to help you out. Even if you have a procharger, that's the kinda guy he is...

articfriends

I agree,a common MISCONCEPTION by guys who have never had a centrifugal supercharger (or ANY blower for that matter) is that there is this big "lag" or lack of low end tq. My procharged 502 had no problem pulling my boat on plane with a 30 pitch 4 blade (had a 23 pitch stock). I sheared the floor out of stock bravo upper gears,sheared off a max machine worx vert shaft etc standing on throttle off Idle so I get sick of people talking out their arse about lack of tq. My current procharged 540 made 800 ft lbs tq at 3000, 850 ft lbs at 3400, peaked at 962ft lbs at 4500 and was still making 850 ft lbs at 5800 rpm's,Smitty