Cruised from Phoenix to Las Vegas on Thursday ... Saw an average of 19.1 MPG @ an avg. speed of 80 and getting into it a little bit from time to time ... In my case it is about a 1 MPG improvement over stock.

 

Hey what psi do you run daily and race.

 

They all have points to talk about. I owned all but the KB set. Never installed but owned.
I really liked the KB size of intercooler.
Magnachargers has a very complete kit right from the get go.
Whipple seems to not support the truck markets like they did in the past.
Procharger was freaking loud on my TBI truck. When I was young ok but I could not handle it now. lol

When you have to choose a company or product to go with go with one you are comfortable with, I would recommend calling all your choices and talk to them. Ask about after the sell tech, warranties, etc. and always deal with the same guy if you can.

Oh and as far as MPG I think the turbo has is. but I'm bais'd. haha

 

This is a totally subjective question as it all depends on the combination, driving style, etc... But I thought I'd throw the latest info into the mix to fuel the debate.

Some of you may know that Audi (well known for their prodigious use of turbochargers) has bucked the trend and developed a supercharged V6 to replace many of their V8 applications. Most Audi/turbo fans are upset with this because historically they have almost exclusively used turbos to provide forced induction. The supercharged V6 offers better fuel economy and torque and similar power compared to the V8 it replaces.

Why did they supercharge rather than turbo? Audi has been able to best the closest competing car by 3MPG... That's Audi's A6 all wheel drive car (24MPG combined) vs. BMW's 3-series twin-turbo direct injected I6 rear wheel drive car (21MPG combined).

Audi spent alot of time optimizing the car for the supercharger and realized something past OEs hadn't done yet... The instant boost from the supercharger allowed for a higher driveline gear ratio (numerically lower) while still maintaining acceptable acceleration. The lower drive gear slowed down the engine during cruising and yielded additional fuel economy. Turbocharged engines in identical configurations suffered from poor acceleration due to lag.

A positive displacement supercharged engine with higher gearing will have better fuel economy than a turbocharged engine while maintaining acceptable fuel economy...

If you were really concerned about fuel economy, you'd be downsizing the engine while boosting it.

But I think if all other things remain equal, you're splitting hairs.

 

If that were the case then why does everyone seem to run such a high gear in a turbo car? Because the turbo likes the load? I plan to run around 3.23 in my Camaro. Most of the guys running Prochargers seem to run a lot lower gear. Positive displacement blowers might be different, but that is what I have seen to be the case.

 

I think Turbo like low gear and the supercharger like high gear.

 

Low numbered gear and the superchargers like higher number gears. A lot of the turbo guys are really happy with gears as low (or high) as 3.08 and 2.73s with auto and sticks. The turbo cars do better with a load to build boost faster. There are far too many instances that support that theory. The positive displacement blowers I would imagine would be the more indifferent of the FI. The centris I have seen the builds of like a higher numbered (lower) gear from what I have seen, ie 4.11 4.30 and the like. My understanding of the Maggies, Whipples, and KB the displacement of that blower makes the motor behave like a much larger engine. For instance a 5.7 in a Vette with a 2.3 KB would be similar to a 7.9 liter motor. Thus the positive displacement, that is why they create such superior low end torque. Much like a motor much larger than the motor it is strapped on to. That is my understanding of them. The centri vs turbo debate are things I looked at for my Camaro. The cam selection was much milder with the turbo, the turbo would act as a muffler which would also quieten the exhaust note of the car. That combined with the fact my car is a 6 speed and I would likely run a 3.23 or 3.08 gear made the choice pretty simple for an all out build that should hit close to 1k whp and still be able to take it on trips and it not be an all out drag car. The Procharger to support that power would have been a F1-R and they are FAR from queit at idle.

 

First off for the MPG on my truck, I had an intake, UD pulley, muffler and a tune and was getting 14mpg, removed the pulley and intake and installed radix and now the best I can seem to get is 12mpg. I definitely drive with a heavier foot now, that blower whine is just addicting. If I could stay out of it and cruise slower on the highway 60-65 instead of 80+ i'm sure I could get better mileage


Most of the guys are running higher gears because they are running high boost applications and can't build peak boost in the lower gears of their tranny first, second, maybe third before the tranny shifts. So by going with a taller(numerically lower gear) they can build more boost before upshifting and therfore go faster.

Also cars are MUCH different than trucks. a 3000lb camaro will like and need entirely different gears to get it moving and cruise then a 5000+lb truck

 

My point was in reference to the statement made about Audi getting better mileage with the supercharger because of the gearing requirements over a turbo. I understand the issue with compairing the Camaro and trucks and their differences. My point is that the turbo vehicles I have had and every one I have been around has had a 3.42 or less. Even the people that have swapped the 3.42s or whatever of 3.73s have swapped. The only turbo trucks I have been involved with was diesels and they don't count. They are geared to tow and diesels redline at 3500 or so. I really think this thread is silly because the difference will come down to driving style, power level and goals, and extent of modification from stock. Basically it is like splitting hairs.

 

Some more VW/audi testing

I had a passat 1.8t and my brother had a gti 1.8t same mods-Revo Software, exhaust. He was faster due to weight and got 4mpg better due to weight same motor and turbo. Now our mpg went up with the software with the higher boost, but we both got the same gains.

Now both of the 1.8T got better milage than my ex-girlfriends 2.0 naturally aspired jetta... All 3 were manual cars and the turbo was a requirement for fun...