Ilmor 700 vs. Mercury 700?
 

Does any one have any info on the new Ilmor 700, and how it compares to the Merc 700 in warranty, price, fuel economy , etc. has the Ilmor been put in any boats yet. how much more is it than the 625 Ilmor?. are the teague, imco, and konrad drive warranty still 1 year on the Ilmor?

Re: Ilmor 700 vs. Mercury 700?
 

If its anything like the 625 vs 600 merc I would go with the Ilmor. Better fuel economy and naturally aspirated. :cool:

Re: Ilmor 700 vs. Mercury 700?
 

There are a few out in the Eliminators for example.

I believe they had a pair in an Eliminator Eagle at the Smoke on The Water run.

Re: Ilmor 700 vs. Mercury 700?
 

The big thing I like about the 700 Merc is the drive. We a have a 38ZR with 700s and the boat rocks. Mid range punch is very strong and the drives react the same as number 6 drives. Merc has a 1 year warranty on engines and drives on this package. we are not done testing but we did have 106 mph out of her. Fuel consumption is actually better then the 600 on this set up. I don't much about Ilmore except I can't stand the noise they make and I know Teague drives stand up well because I have one on my 26 Donzi with 780HP behind her.

Re: Ilmor 700 vs. Mercury 700?
 

Their are quiet a few 700 Ilmor packages out there. I would imagine the pricing for the 700 Ilmor would be in line with the merc package. As for fuel economy, I have heard that the 700 Ilmor has been tested and found have about 40% to 50% better fuel efficiency than the merc 700. Will be interesting when the test results are published. You still have the weight savings as well.
The 625's that I have are very fuel efficient. I have a 41' Velocity and have just made a trip last weekend. Total mileage for the trip was 364 miles (GPS) and I burned a total of 258 gallons of fuel. This comes to 1.41 mpg. Most of the trip was around 3500 rpm, and some short burst on the wood. This is with 4 adults and 2 kids with fuel, water, suitcases, food, etc. Very happy with the motors.

Re: Ilmor 700 vs. Mercury 700?
 

and 4 gallons of margaritas

Re: Ilmor 700 vs. Mercury 700?
 

The Ilmors are not under as much stress to make the same horsepower and the exhaust resonance is better compared to a V-8.
V-8's are "so yesterday"!

Re: Ilmor 700 vs. Mercury 700?
 

Let's not hasten to any quick snap decisions here.
First, Ilmor is making some wonderful engine packages and the new 700 seems to be a real nice piece. Ilmor has had good sucess with its engine packages up to this point and they should continue in this trend.
But lets be carefull to look at a few facts.
First the Ilmor motor makes its peak power at 6100rpms and its torque maxes at 650 ft./lbs at about 4400rpms. The Merc 700 makes its peak power at 5300rpms and makes substaintialy more torque over 750 ft/lbs between 4000 rpms and 5000rpms.

The lower weight of the ilmor package will be an bit of an advantage in a twin installations although when Ilmor releases a new heavier drive for this engine in the long term who knows what the weight advantage will be? This engine is going to give the current drives they are using a bit of an overload in long term use.

When you really consider that most high performance boaters still spend over 80% of their boating hours between 3500 and 4400 rpms its really important to make real world comparisons of torque and power at these rpms where the motors spend almost all of their running time.

The Merc 700's as supercharged will obviously not have the longer engine life of a naturally aspirated motor but the higher rpm range of the Ilmor 700 will limit its engine life also and neither of these motors will be an inexpensive rebuild.
This is why we at Raylar still believe that the naturally aspirated big cubic inch-high torque, moderate rpm motors still represent the best power / versus cost benefit in marine high performance engines.

Our HO750 -600 inch normally aspirated motor makes 765 hp at 5200rpms, 850 foot pound of torque at 4200rpms and freshwater cooled complete ready to drop in and run sells for just under $32K. This motor will also give real 500-750 hour engine life in real world use.
Let me review here, 50 more horsepower, more torque, longer engine life, and no supercharging or high rpms to make power, What's right with this picture?!!

Ray @ Raylar

Re: Ilmor 700 vs. Mercury 700?
 

The Ilmor has two more cylinders to cope w/. More moving parts, higher RPM...I would go with the Merc running a tame SC PSI at lower RPM's. Gotta have the BB V8 sound too.

Re: Ilmor 700 vs. Mercury 700?
 

Ilmor is a 800 pound motor.
BBC is a 950 pound motor.
Supercharged BBC is a 1100 pound motor.

Ilmor is a 505 inch V10 with a 3.96" stroke. This means that at 5909 rpm it has the same mean piston speed as a 572 BBC (4.5" stroke) at 5200 rpm. So the rev stress and estimated ring wear are comparable. Valvetrain is obviously going to be moving faster, but we know that with stock components, a BBC does not have great valvetrain stability at high revs, whereas the Viper heads and valvegear were designed in modern times and has a more stable valvetrain geometry.

The lowdown is this: The Viper motor does not have a crankshaft that will support heavy duty blower service. It's long, and optimized for the power levels we are seeing now. There's a known formula for big supercharged HP with a BBC. The Viper may have the potential for close to 800 marine horses, but with the parts available now, that's probably the upper limit.

We know it doesn't take a lot of magic to crank out well over 1000 from a meaty BBC.

The Ilmor is a sweet motor. It builds power with revs, so you don't have the midrange grunt of a huffer on a big inch BBC. It's light and low profile and will fit under most hatches. It doesn't sound bad, but is a different sort of exhaust note. At 710hp, it will be hard on any Bravo drive.

The Ilmor is a viable option. Just not the answer to everybody's application.
By the way, I know where you can get a pair of some perfect low hour 625's under warranty (check the classifieds).

mc