is there a diff between the two besides sound i mean performance and cooling side of things and if so is it worth the 100.00 diff in price

 

I think you mean the Stage III and Stage IV - I talked to Paul at HTT before buying my Stage IV, and he said the IV would cool slightly better than the III because of the bigger exducer. They should sound about the same.

 

so it sounds like the stage 5 is not worth the extra 100.00 for me sound like they are about the same does the stage 3 also have a 6 blade

 

The Stage 3 is an 8-blade design.

 

Iam slow is the 8 better than 6 or is 6 better than 8 or does it matter

 

Well, in this case 6 is better than 8. I don't know the specifics of why, except that the 6 blade wheel on the Stage 4 has a larger exducer (the big side of the wheel is 86(?)mm instead of 83(?))

 

i would take a stab that the 6blade is better because less weight when you are spinning something that fast is a positive. but if the exducer is larger they may even out. if it's the same rotational inertia then spool should be the same (right? lol) from what i hear the stage IV flows 10% more.

 

This is why when you buy a stage IV they have a backplate that has been bored out bigger to take the stage IV wheel. If you can do it your self on a lathe then just ask for the proper dimensions.

 

To my knowledge, blades on a turbo work the same as blades on a propellor of a boat. The fewer the blades, the more efficient the airflow will be but having more blades also illiminates wobble under load. The actual blade design itself needs to be calculated into the equation as well.

A turbocharger turns wicked rpm so the amount of blades or lack there of, can be very critical to the performance you desire.

Keep in mind this is taking my knowledge from boating and applying it to turbochargers.

Hope this helps,
Mike

 

I would think that trim would be more importnat than the number of blades. Trim being the relationship between the inducer and exducer diameters. Assumin all else remains the same, the larger the trim the more airflow. However as wheel size goes up efficiency goes down. The idea is to increase trim without increasing the overall wheel diameter. TRIM=(MINOR/MAJOR) squared x 100

The compressor side of the turbo isn't really responsible for spool-up times either, so you don't need to be concerned with that factor. Turbo lag comes from the turbine side not be able to efficiently accelerate the shaft. Compressor choice affects the temperature at which the air is expelled and thus its density. Hope this helps.