I need some help guys. I've got an '04 VHO that is dying for more HP!!! I was going to go with the STS, but have heard it has no low-end pwr and I heard superchargers(Radix, Whipple) lose power when you get up around 100MPH or so. And also with superchargers do I need other performance parts(headers, cam, etc.) or not (I have a Volant, and Flo-Pro muffler already)? Any info would be helpful.

And if anyone knows of a good performance shop in the DFW area that would be awesome too.

Thanks,
Caylon

 

You should try modding your truck with things that will work with both a supercharger and turbocharger. I would get a custom tune and a stall. I just got a nelson tune and it made a world of differance. Getting rid of the TQM made it much stronger down low. And adjusting the shift points made it stronger up top. But if you want your first mod to be forced induction, go for it.

 

I'll pitch in on the STS... To say it has "no low end power" is a bit of a misnomer. With my 5700lb pig, it is only "ok" from 0-20mph. What I mean by that is that the turbo is starting to come on, not a ton of power. By the time I hit about 20mph, it starts hitting pretty hard. It does NOT stop as high as I've gone (110mph). It literally keeps you pressed in your seat, hard. Harder than either of my stock Lightnings (which ran about 14.1-14.2 here in the AZ heat stock). The Lightning, for comparison, was much faster 0-20mph. About at the 1/8 mile, or what, 70mph is where the Lightning really starts to lose steam. My Denali with the STS is pulling much harder at that speed. To fix the 0-20mph "problem", I'm going to put in a stall which will allow the boost to hit almost immediately. My Tune is not quite right yet, and I'm only at 7psi right now. As of Monday it will be at 9-10psi and the hit will be even harder than it is now. My guess is that the power through AWD will be in the low 400hp, 440ish tq at 9psi. With AWD there is roughly a 28% drivetrain loss. So with a VHO you'd be maybe 430/470. I'm also on a 91 Octane Tune, and running a PIG RICH 10.7 A/F right now.

I've ridden in two STS trucks. They were faster out of the hole than my truck, but after 20mph or so, they weren't pushing you back like the STS kit.

Price: the Radix kit would have been maybe $1500 less than what I've done so it's tough to compare. I understand a fair comparison would be Radix "basic" kit vs. STS "basic" 5psi kit.

Cost-wise, I'm sure I won't stop. I'll end up with a new trans/stall, FMIC, etc... If cost isn't as much of an object, I'd go STS. If you want to drop $6000 installed and be done, go with the Radix. Don't forget to ride in one of each (at least) if you can. Everyone's preferences are different.

My personal opinion? I couldn't be happier with a big fat V8 being boosted by a Turbo! The sound, the feel, the increased gas mileage (joking)

Either way, your truck is going to be a hell of a lot more fun!

 

Well, I guess if you want characteristics of both, look into centrifugal superchargers.. procharger, etc.

 

Pro- lots of power
Pro- fun to drive
Con- short tire life
Looks like the pro out way the cons. I'd say do it, either way you'll be happy.

 

Pro of supercharger is quick boost buildup and application specific kits readily available.
Con of the supercharger is belt slip, and lost crankpower that it takes to turn the compressor.

Pro of turbocharger is no belt slip, dosent use crankpower to spin it.
Con would be insufficient source of information for your buildup. You have so many different options, and several variables that will either make your work perfect, or adversely effect it (turbo lag, low-lowend).


I think turbo is the way to go if you can research it and get the best setup for your application.

 

Procharger would probably give you the most top end power for a supercharger kit, but not have the low-end of a Radix. Add a stall and the low end problem isnt really an issue. I looked into the Radix, Procharger, and STS. I eliminated the STS due to where it mounts and the fact that I live in Chicago with tons of road salt- and this is my daily driver. I also looked into the Livernois turbo kit, which looked like the best power and bolt-in option, but was a little pricey. After weighing all my options, I went Procharger D1. Got a good deal on a used kit also.
IMO I would say the Radix is the most complete kit and probably bst for something that does a lot of heavy towing. Procharger will most likely make more top-end power. And the Livernois kit is probably the best overall power and pretty complete- but pricey.

 

I think the best question for you is What is your budget for the project? Knowing the answer to that will help answer what is best for you..

 

So how about a radix and a procharger? Best of both worlds, right?

 

Or just do a big Turbo and crank the boost wherever you see fit!!