700HP Blower vs. NA
 

If one was on a budget and needed 700HP for a marine engine powering a single engine cat would you go blower or NA? I'm not an engine expert but know just enough to be dangerously wrong. In theory the blower motors have more moving parts (more stuff to go wrong) and put more undo pressure on the valve train, rings, etc. However I had a car with a blower installed by Roush drove the **** out of it (tracked it) and it ran great all the time. I also fell in love with the noise from the blower under boost. However I don't want to have a boat that doesn't run right half of the time and needs a rebuild every season. I'm just looking for general thoughts and opinions. Thanks in advance.

Stay away from blowers on boats !! I am not saying that for the usual reasons..... I had a driver with a blower and drove it for 100,000 miles before I sold it with no problems.. I also have Lotus Turbo Esprit and no problems what so ever.
The problem that arises is the fact that very few people know how to work or better yet tune a marine engine with a blower.
The fact that most engines these days have an ECM or are computer controlled makes them very difficult to tune properly.
and very few people know how to do that!!!! You can look at this web site as an example of all the horror stories when someone tries to put a blower on a boat...Lunch time for the engine ! or a very expensive rebuild.

I am sure I am going to catch a lot of flack over those comments - but thats the way I feel.... If you still want to do it find a company that really know their business and once installed dont get greedy or go crazy expecting miracles from your engines... With great power comes great pressure -- on the engines !!!!

Good luck

Jim

on a marine engine, you can't go wrong with a blower on a boat. For the HP gains you can't beat them. Plus there are plenty of combinations that are proven. Talk to Eddie Young or some of the other professionals on this site, they will steer in the right direction

Problem is that people bolt blowers on motors, who have no clue, and fry their engines in 1 hour.

Their is two trains of thoughts on this. Most of it depends on what you have to start with for a base. For example, lets say you have a 502CI merc. To get 700HP N/A out of it, you will need to run really good flowing heads(expensive), 9.5:1 or higher compression, solid roller camshaft with lots of lift and duration, very high valve spring pressures, and probably turn the engine to 6000+RPM to even get close to 700HP.

Or, you can leave the stock 502, put some cometic head gaskets in, a good valve job, a mild hyd roller camshaft, install a blower, and make 700HP.

The blower setup would more than likely last longer, and idle better around the docks. My vote is for blowers, as long as they are properly tuned and setup.

Blower !!!!!!!!!!!!!!!!!!:ernaehrung004::ernaehrung004::b oat:

I run a mercury racing 600 that whipple stage 2'd. I am in love! Idles perfect, runs up to 96 mph and cruises nice. Blower power is addicting 168 hours on motor.

I don't know why some people are so scared of blowers as stated before it's all in the setup. If they were so bad why would merc use them all the time.

You pretty much nailed it right there. Problems associated with blower engine failures (or any engine failure) can be attributed 99% of the time to either an improperly assembled or tuned engine, or improper setup, rigging or installation. Most problems are self inflicted by either guys wanting to save money by either wanting to do it themselves or paying the cheapest shop. Now, just because you spend a ton of money on an engine doesn't mean it will last neither. You have to do your homework and stick with a reputable shop. There are several of us out there that are capable of making an engine live a long life.
Eddie

The blower will actually make the power with LESS stress on the valve train. You can run a smaller cam and don't have to spin the engine as fast to make the same power. I would go SC'd if I wanted to make 700hp.

IMO it matters only from where you are starting.

If you are starting with brand new stuff from the ground up, then NA is the easiest on the budget. Big CI are not very expensive any more and not having to buy all the parts for the blower set up will save you a ton of money.

If you are modifying an existing engine and you are starting with something small as mentioned earlier then the blower is the way to go. You don;t have to have crazy expensive set up heads and you won't need as much cam and the valve train will last a little longer. And it is way cooler to have those blowers when you can get them.

But no matter which way you go, make sure it is set up right or it won't last. :coolcowboy:

Good luck and have fun. Keep us posted.