I decided to be scientific when making my decision.

What I did was observe my driving habits and behavior over the course of a week. What I found was that 70% of the time my driving was under 3000 RPM, and 90% of the time it was under 4000 RPM.

I encourage anyone considering F/I to record the same data for themselves.

Since the time from idle to 3000 RPM is where the Radix does its best work, the decision was really a no-brainer.

 

I really like this kit. So what rpm is your boost kickin in? Can't u get a better fuel pump so u don't have to worry about it? Is our stock oil pump not working anymore

 

The STS has an oil return pump that goes from the turbo in the back of the vehicle back up to the motor... That's what most are worried about failing.

This is why I said front mount, no oil pumps, way less tubing, normally faster spool time (with properly sized turbo) and all the power potential of a turbo setup, its a no-brainer for me as well... I like being fast

 

Which results in the quickest 1/4 mile time Lol.

 

The thing about a turbo is that you can drive all day long and not be in boost using the extra fuel but when you want the power it's there. Before I got the turbo I drove simular to the guy above because there was no reason to step on it. When I got the turbo my driving habits changed dramatically as I was always in boost. After a while I just wanted to drive normal and get good gas milage most of the time then step on it every once in a while. The turbo allows me to decide when I want boost and when I just want to drive. In the long run I garentee the turbo will net much better gas milage and much more power as it is always going to be more efficent than a supercharger.

 

My combo has changed alot , I've had a 5.3 with a 60-1, a 6.0 with a 60-1 turbo (too small), the 6.0 with a GT-67, a 5.3 with the with a GT-67, and now my new engine a 6.2ish with a GT-67 (too small). Even with the 5.3 and the GT-67 the lag was not an issue.

I feel it is very hard to talk "lag times" on forums, what maybe acceptable for some maybe considered too laggy for others. ALSO tuning plays a HUGE part in lag time.

With that said, My boost comes on about 2000-2500 rpm, I towed our company truck home yesterday, and boost was coming on WAY too fast, under 2000 rpm...

Talk to the guys at STS about pump options. I'm not going to lie, I worry about the pump, but after 3 years of nothing but performance out of it, it's kinda hard to justify.

It' is truly sad that BC's pump went out, I think he would have liked the kit after he got use to the way the power comes on..

Better fuel mileage is possible, but worse gas mileage is also possible, with both kits. though I think fuel mileage could be slightly better with a turbo vs the supercharger..

Here is on example, My old 5.3 got 16insh on the highway. after the turbo install, and if I set the cruise I got 18ish. When I installed the 6.0 milage was still at 18inst on the highway..

Not always.


Here is a video of my old 6.0 with the GT-67 with a .96 a/r, This is the best video that shows lag with the system. RPM is at 2,000, I stab the gas, converter flashes to 3,000, engine hits full 12 psi of boost by 3500, tires are gone. That set-up was basically all STOCK components with the STS kit and some meth. If it would have been a Radix, boost (9ish psi) would have came on at 3,000 when it flashed.

30mph roll

It really comes down to what I said earlier and how you want the power to come on. A turbo "comes on" to power in a much softer way, but continues to pull you back in the seat, a radix is sudden, that tends to not pull as hard up top. When you brake stall both set-ups, all bets are off when it comes to lag.
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As far as front mounts. That would be the answer to the oil pump worry, but at the cost of CARB, and under hood temps. I truly feel the STS is the best package for towing applications. All the power of a turbo set-up, without the under hood and EGT worry's of a front mount. BUT if you don't tow, all of this doesn't matter much. I also feel the front mount goes a bit further in the "do-it-yourself" category though. But if want a turbo, it is the ultimate set-up.

 

why is the g67 too small for the 6.2 engine? Will the predator that Sts provide me have different settings for towing? I don't want to blow up the motor while towing my boat to havasu.

 

With a turbo you can also help the spool up with the tuning. Small adjustments to the timing and fuel in the right spot can really make a difference.

Also if you are running a auto trans you can downshift and POW instant boost!

 

I can modulate/moderate power as well, with my right foot, with the Radix. My preference is to have full boost available, on-tap, right off idle. You don't have that option with the turbo (unless you count a converter flash to 3000 RPM as "off-idle" )

That's not saying I don't like turbos....I absolutely LOVE them. What I am saying is, that for a 6,000 lb. truck, I prefer off-idle power.

How about a 'properly sized' turbo? My definition of properly sized is, boost that comes on low on the RPM scale, comes on smoothly, and lasts to redline. My reference would be the BMW 335i or 535i - that engine is a twin-turbo, straight-6 where boost comes on almost immediately, and smoothly - no perceptible lag - and lasts through to redline.

It seems to me that many people here prefer the violent onset of boost that comes with what I would consider an 'oversized' turbo.

 

Funny, I can drive all day long and NEVER get into boost either. I am very interested in your theory on why a turbo of equal size would be more efficient that a supercharger? Gas Mileage? I am getting about 21 mpg average and 27+ on the highway with a TVS on my G8.