Is the Billet Compressor Wheel vs the Cast Compressor Wheel Worth It. The Billet Compressor Wheel is Usually Over 100 Dollars More than the Cast Compressor wheel, Which Leads You to the Question, is the Billet Compressor Wheel Worth It or is Your Money Best Spent Somewhere Else? I Made This Video To Help You Make an Educated Decision.
Some Billet Compressor Wheels Weigh Less than the Cast compressor Wheels and Some Billet Wheels Weigh More than the Cast Compressor Wheels. I Would not Make a Decision Based on the Weight Alone. I Would Chose Based on Usable Surface Area that the Blades Can Use the Capture More Air. In this Video I also Demonstrate an Example of a Billet Compressor Wheel that I Didnt Think Was Worth It. The Main Advantage Of Billet Compressor Wheels vs Cast is:
- Lighter Weight (some cases it is heavier)
- More Room for Air Flow
- More Durability (Cast Wheels can Have Air Pockets Creating Weak Spots, But Billet Wheels are machined for Solid aluminum)
If You Would Like the Take a Look at Our Billet Wheels Available, You can Find Them On Our Ebay Store Here.
I’m currently having my GT3071r-wg T25 .86a/r 90 trim upgraded with a KTS Billet compressor wheel based off of the standard 56 trim 71mm/53.1mm cast wheel. After researching the issue between billet and stock cast, I chose a wheel which has many of the characteristics you described here as advantageous for billet over stock. The hub of my KTS is about 2 mm smaller in diameter than stock, trimmed down Exducer blades with extended tips that are 5.4mm beyond the standard 71mm. (75.4mm overall) 30* angle. The Inducer is taller as well, and the Exducer blades are swept back at a 60* angle. The wheel even has a cutback of 1*, which I tried to research and found little info on other than it improves airflow. The wheel has the same 6 + 6 style as stock, and is advertised as a bolt on to the stock GT28/3071 56 trim turbo. TIm’s Turbo is handling the install, and I can confirm Tim isn’t really crazy about what aftermarket billets can do. He’s more favorable to billets made from the turbo manufacturers themselves… i.e. Garrett, BW, IHI, Holset, etc.. He says the aftermarket is too full of hyped up billets that are essentially duds, or oversell their benefits over cast wheels. Without the ability to flow test and map them, he is suspicious of their claims. I understand his point, but KTS seems to come highly respected in what they’ve produced so far. It seems as if they rely on the tuner world to give hands on feedback on their wheel designs, and they modify the wheels accordingly to suit. Thus, it would seem they are using some kind of method to determine what works and what doesn’t.
With that in mind, my goal was to broaden the map of my GT3071r-wg, pulling the surge line left and improving boost onset. Since this turbo is going on a Mercedes Diesel (old school 300D 2.5L IDI) being tuned for greater power and efficiency, after calculating engine airflow requirements for my power goals, the standard GT3071 56 trim was a little to far right for my tastes on the map. My only alternatives were selling the turbo and scaling back to a GT28, but as much as these engines flow I was afraid of downsizing the turbine further. Since Garrett basically leaps from the 60mm cast wheel to the 71mm in the GT series, there was no inbetween sweet spot wheel. They resolved that issue with the GTX series, adding a 63 and 67mm wheel… but that doesn’t bolt onto the GT turbine shaft. I wasn’t about to spend hundreds more changing CHRA’s and modifying housings, so custom billet seemed the only cost effective answer. If I did my homework right, and KTS is on top of their game, I should get what I want out of this wheel… unless I missed something. I’m only doing a max of 19 psi, so any benefits of increased max PR isn’t really needed. Nice to know it’s there… but without a map, the most I’d feel comfortable trying would be maybe PR of 4 to 4.25 instead of the stock 3.5 Both of those levels are far beyond my paltry target of 1.4 PR, so it’s not a big deal.
From your experience what do you guys think? Did I at least have the right idea of making this billet choice worth it over the stock wheel? It only cost me $109 and looks like a decently designed and milled piece.