In2Deep

Folks


So, I'm approaching 300 hours on my 496 Mag HO in my '02 Heat open-bow. Motor is running great, Bravo Ix re-built two seasons ago, and running strong. I've never any serious issues with either motor or drive -- but the go-a-bit-faster bug has bitten. I've decided that I'd rather keep the Heat than go out and buy a new boat. So, time for a fall/winter poroject.

Project Objectives:

1. Push my heat to mid/high 70's MPH. 80 MPH would be a dream.

2. Do that reliably (no point in spending all my time in the shop, or stranded at the dock). I do not know how to fix motors myself. I much prefer "turn-key" reliability -- or darn close.

3. Don't break the bank too much (kids gotta go to college).

My normal boating conditions:

Fresh water (Lake Travis, LOTO). I don't go hunting for the big waves -- prefer a bit smoother chop, or moderate slop if it turns out that way.

Here's what I'm thinking; several options.

Motor Option 1:
Re-build the 496 the right way (proper top-shelf parts to accommodate....and add a Whipple?

Motor Option 2:
Raylar rebuild of the 496 Mag HO?

Motor Option 3:
525 EFI with whipple? Find a fresh(er) pre-owned 525 and build from there? Or 575 SCi (would that fit? weight issue?)?

Motor Option(s) 4:
Re-power with some type of high quality normally aspirated or EFI custom 700-800HP motor, perhaps a a "GT" (Gary Teague, built), or other big HP motor you see for sale all the time?

Mandatories I know I'll need to do as part of the motor upgrade.

1. New headers (CMI Sport Tubes I hear have delivered great results).
2. New or re-built Drive (XR?)
3. Dual-ram hydraulic steering
4. Trim tabs (or is this optional at this moderate power/speed goal?)
5. 1" drive spacer
6. New prop (pitch TBD)

So, I'd like to poll the Nordic experts here who've tinkered, tweaked, fabbed, re-propped, drive-spaced, and done the linear algebra to gauge relative success -- which path would you recommend?

I'd be very appreciative of your perspectives and opinions.

Thanks folks.

Dave

bobl

Well, as you know I've done as much work as anybody on the Heat. The Raylar kit with headers (560 HP) will get you about 72-73 on Lake Travis. Same for a 525. I had a naturally aspirated 540 (600 hp) that ran solid 75-77 here. So it will take a supercharged engine or a pretty radical naturally aspirated engine to get an honest 80. I've got several supercharged 496 projects going on in the next month that would be a pretty good setup for you. Give me a call. 830 6935591

Bob

Southocg

Dave,

The dollar cost (cash today) to achieve the speeds your looking for are going to push into the mid 20's and up.
I have a buddy locally that has an 02 w/a 496.
He had an XR drive with hyd. steering to the helm so he didn't need all the extras per se.
He put a whipple on it with no exhaust and it ran him 13K and he picked up 10mph.
He now runs in the mid 70's.

You can expect to spend about the same if you go the Raylar way. Nice stuff but your going to pay for it.

If I was going to do anything to a base model heat....
I would buy a rebuilt 525 blue motor and leave your drive alone for right now. As long as you don't drive like an idiot, the drive will give you hours of trouble free boating.

To get the 525 with exhaust is going to run in the low 20's.
Assuming you can get around 7 for your motor, this gives you an out of pocket cost of around 13 which is right where all the other kits are going to put you. The once exception here is that your re-sale should be much better with the 525.

Speeds with the 525 will put you in the legit mid 70's.
To push up over the 80's your going to need 600 plus.

My boat as it sits right now runs 89 if everything is perfect.
With a couple modifications, should be in the low 90's and that's with 700hp (just to give you an idea what you'll need to push the boat).

OCM

Gary Teague , has GT performance. Gary Taylor has (TPI) Taylor performance.
Tim
oregoncustommarine.com

Raylar

Why rebuild a 300 hour 496HO now? Take a compression and leak down test and if the compression is close in every hole and around 150-160 lbs and leakdowns are high, don't touch your block. Keep using it and get the 500-750 hours that are easily well kept 496's! will see!
If you've got a good 496HO as will be shown by tests above, drop one of our 525HP top end kits on with a set of good exhaust headers and the 560HP you will see will get you to the mid 70's with some good x-dimension work and prop dial ins. This should cost around $12 to $13K depending on who and where the work is being done. This will use the same 87-89 octane fuel you are using now and the fuel economy will improve slightly over the stock 496HO, yes even with 560HP!

Then a year or so down the road when the motor has 500-750 hours, redo the block with a Raylar forged internal HO600 shortblock, reporgram the ECM and upgrade the throttle body and Whola, you are at 625HP with the previously purchased Raylar parts and still running on 89 octane fuel and a new rev-limit of 5400rpms that will get you close to your 80mph dreams. This short block upgrade with ECM reprogram and a throttle body will cost you about $8K more plus labor.

Whoever is buying new complete HP525's blue motors for low $20K is either a magician or they are stealing them. Call any dealer right now and check that price! Think you will be quoted more like $28K at the low side plus freight!

We do new Raylar HO525's with custom paint, and headers,
With Dana's they are about $21K and with CMI's they are about $23K dpending on other options plus freight.

Build up a good supercharger internal 496 and plop a nice Whipple on top with special tuning and bigger boost lets say 7-8lbs and the 700HP this can give you will get you to your magic 80mph level! Be prepared to spend about a minimum of $19-20K to do a proper Whippilized 496 of this power level. Also be prepared to use and spend about twice as much fuel as you use now, be prepared to buy only 91-93 octane premium only! and get ready for rebuilds at 250 hours.

There, now you've got some real figures to sink your teeth and brain into!

Best Regards,
Ray @ Raylar

Southocg

Whoever is buying new complete HP525's blue motors for low $20K is either a magician or they are stealing them. Call any dealer right now and check that price! Think you will be quoted more like $28K at the low side plus freight!


Nobody is buying "NEW" complete HP525's for 20k.....
I'm pretty sure I said, buy a "rebuilt" for 20K. That can be done and it is all the time.

For whatever reason, people love Merc power.
I still think your re-sale will be much better with an HP525.
Much more so then with a whipple or a Raylar kit.

Good luck and happy boating.

johnlomant

I have a 525 for sale low hours like 48. Id sell it for $19000 complete with headers and all components.

kennyo

What's wrong? Mid 80's not fast enough for you???

In2Deep

As expected, you all came through beyond my expectations. This is very useful information, and exactly the type of real world and first-hand experience -based opinions I was hoping for. Definitely something for me to "chew on".

Thanks, everyone.

Dave

Southocg

My point exactly.......

So say you buy this for 19K and you have another 2K to install and re-rig, your into it for 21K.

Sell your motor for 7K and your in it for 14K, right where I said.

This is by far, dollar for dollar, the best way to go...
In lieu of buying a new boat.