Anyone have direct experience with one? I have seen some nice units with some pretty strong claims about HP gains. Which manufacturer is best?

 

I have a gear driven Magna supercharger on my '03 RoadKing.
Dealers wont touch it, even warranty work. My Indy wrenches it but its his first gear driven, he has a lot of experience with the belt driven intercooled unit. Says he can get into the 100's Easy. Mine only get 88hp and 89tq due to too small of injectors.
Hope you got the cash to redo your engine. If you want speed buy a buell, or some other crotchrocket. Something designed to go fast, save the trouble.

 

So true. I couple of years ago I decided to put a Paxton on my Durango R/T. It ran great, until the tranny failed. So I had a beefy street/racing trans built. The truck ran great and shifted well, until the engine developed a knock. So I had a built engine made and dropped that in. Now it runs well and is built tough enough to withstand the pressures of boost. But with the money I spent getting it there, I could have bought a nice sports car.

If you want to go ballistic fast, buy a ZX-14, or a Hyabusa.

 

Some things to consider .......what is the application? Racing or cruising? Tremendous HP gains can be achieved in racing applications. The main factor involved is heat management of the discharge airflow. Hence intercoolers.
In racing applications, the supercharger is run for short durations so you don't have a dramatic effect due to the "heat soak" of the supercharger case and surrounding components. This "heat soak" will contribute added temperature to the air being compressed. Compressing air creates temperature in itself, the more you compress, the greater the temperature rise, so now if you add the additional temp due to the "heat soak", your discharge air temp is even greater. You can actually reach a point where you lose HP even with a boosted engine due to the discharge temps being so hot.
MHO is supercharging an air cooled engine used primarily for cruising is not the best situation from a performance perspective, but the "WOW" factor is certainly there.

 

Thanks guys, that is what I wanted to know. i miss my '67 Chevelle, guess I am trying to relive the old days when you felt the g forces of extreme horsepower. Guess those days are gone forever.

 

Dixie, have you ever thought about nitrous? The torque gains can't be beat. Get it tuned right, and the only problems you will have is wanting to go with a bigger shot and the bottle not lasting long enough. jt

 

No JT, I haven't thought about nitrous, the idea of a supercharger was appealing to me because it gives you a big HP boost and seems to be a mechanical enhancement that achieves gains without screwing up your engine. I probably should just change out the cams and accept the fact that I am only going to be able to get X out of my bike and be satisfied with it. I have a tinkering problem, I get something and learn its characteristics and then I start tinkering with it , trying to improve it. Maybe I should just leave it alone.
Hey, you are right up the street . I am the last house on the left where Morganton Rd. goes into Haymount, stop by and see me sometime and I will buy you a Guinness, or two.

 

Your bike has now been "flagged" as tinkered with. Good luck selling it.

 

Dixie - You are looking in the right direction for HP gains. The majority of Harley riders out there buy the bike, feel the lack of power and start modifying them in various ways. Only a few have actually gone the forced induction route because it is unfamiliar territory for some of them. Most will suggest doing a cam upgrade, or if the urge for more is there they will go for a big bore kit of some kind.

If you want a lot of power and something straight forward as many do, the big bore kit is the way to go. You will easily drop anywhere from $1000-$3000+ for a big bore kit depending on the parts and size you are going for. With the big bore kits you can acheive a range of 100-130hp out of the build if tuned correctly.

When you start looking into the forced induction upgrades such as a supercharger or turbo setup things can get a little more involved. The kits sell anywhere from $2000-$5000 or more and are advertised as direct bolt-ons to a stock engine. The kits will produce a good amount of torque and hp numbers once added, but the kits are preset from the manufacturer for the level of boost it is pushing. When you get "boost happy" (which is very common), you keep wanting to bump the boost level up more and more. The problem here is your stock pistons will not take the abuse, along with other parts inside. As long as you just install one of the two types of forced induction systems with the preset levels you should be fine, but expect to spend a good deal of time with your tuner, or finding a good one to work on it.

I have been working on a turbo project myself for sometime now. Though I do understand the amount of R & D that goes into a turbo kit, I can't really bring myself to spend the $5000 for the kit, especially when I have found the majority of the information and parts at little to no cost. For example, the turbo used in the Trask systems is advertised as a modified Garrett unit, what has been modified I am unsure (there is little you can change on them). The same turbo can be purchased through an authorized dealer for under $700, adding in the other parts and fabrication for my custom kit has only come out to about $2500 (this includes a Tmax system, Injectors, turbo manifold, downpipe, Blow-off Valve, upgraded clutch and other misc parts). In my build I plan to re-work the engine and have it bored out to at minimum a 113" if not larger, this will add another $3000 or more to the entire project, but I will feel good knowing the internals will handle the abuse.

My advice to you is to take a good deal of time and research as much as possible to fully understand the kits and what is needed for optimum dependability and performance. If you want the motor to last I would strongly suggest at least swapping out the stock pistons for a set of forged ones (either stock bore or larger), but also keep your compression ratio around 9.0:1 to prevent substantial damage. If you have any other questions feel free to ask.




Ken - Just by modifying a bike, car, or even a truck people have no issues selling them. The key thing for the buyer is having a good mind to ask about maintanence, test drives, and also having a good tech take a look at it before handing over any money.

 

It would be a cold day in hell before I'd buy a Harley that had a blower on it. Unless I'm buying it as a beater to drag race.