Such a blanketed statement.
And then you go on to make a lot of your own... Some of what you say is accurate, but it sure seems like you haven't had a high hp turbo car of your own. I actually do.
Turbo power bands as a general rule are short, violent and peaky and not nearly as controllable as that of a PD blower and they get even more so the bigger and more powerful you make them.
By comparison to a blower, maybe. But you can have a turbo that spools at 3200 RPM and carries the power out to 8500+ RPM, too. I wouldn't call more than 5k RPM a short powerband. Likewise, my old twin-turbo setup spooled at 2200 RPM, and carried the powerband out to 5500RPM where the stock cam caused the powerband to drop off, not the turbos.
Sure, they can be set up conservatively enough that they’re bearable to live with on a daily basis, but those cars aren’t the devastatingly high horsepower, high torque street terrors that most hot-rodders associate with turbo cars and they’re certainly not the set ups that make PD and Centrifugal blower guys run home, crying to mommy.
The most conservative turbo set I owned was an incon twin-turbo 302. The turbos spooled at no-kidding 2200 rpm, and the car made 420rwhp with basic parts - GT40 intake, GT40 heads, a throttle-body, injectors, and roller rockers. It had a stock cam. It idled, and drove like stock, much to the disappointment of many people who asked me to start it up so they could listen to it. It was so quiet, which I absolutely loved! This combo wasn't going to send anyone crying to mommy. Maxed out, these turbos probably would have made in the neighborhood of 600rwhp. It wasn't just "bearable to live with." I drove this car every day, and it was amazingly streetable - at least as good as stock.
Size and set them up the way they need to be for people to make these tire shredding, insane horsepower and torque figures so many turbo lovers talk about and they turn into a complete nightmare to drive and own.
You need to come for a ride in my car. I have a 1200 hp turbo - is that devastatingly high enough to be a "street terror?" It spools at just over 3000 RPM and carries it all the way up to 7k. You make it sound like my car is just "bearable [enough] to live with on a daily basis." I defy any similarly powered blower motor to be as bearable. I have a 228/224 114LSA HR cam that idles comfortably at 800rpm, pulls plenty of vacuum, and got a verified 22mpg with 3.73 gears on the highway, and that's an old school 5.0 getting that kind of mileage, too. That's as good as or better than stock despite higher gearing and lower compression! Yet, with the go-pedal down, it made 762rwhp, so far at 14.5 psi. The only thing that's keeping me from maxing the turbo out is the weak link in the drivetrain, my TKO. What I mean is at 1000rwhp it wouldn't drive differently. I'm pretty sure I'd have a little low-rpm buck at less than 1300 rpm in 1st gear, but I honestly couldn't tell you that for sure. I'd have to go and check. I'm just assuming that based on a similarly sized cam I had in my old n/a 302. Then again, now that I can tune it myself, it wouldn't surprise me to find that the buck is absent.
They run hot, they're inconsistent, they’re high maintenance and they're generally a PITA to live with on a daily basis and on top of it all…they have terrible street manners.
Define "run hot." My car will stay between 185 and 195* all year around, even in the 110* summer heat at Fort Benning, GA. Granted, I put a badass cooling system in the car in the form of a Ron Davis Radiator and twin spal electric fans, but I like my a/c cold believe that you can never have too much of a cooling system
I agree with "inconsistent." Heat soak affects PD blown cars too in the same way, though. Neither will be as consistent as an n/a motor. Still, you can be fairly consistent if you bring temps to a standard before each run.
"High maintenance" is a relative term. Sure, more moving parts = more maintenance than an n/a motor. However, once you get the turbo motor together, the only difference is the turbo itself. These things can go for 100,000 miles, without needing a rebuild, though. The rest of the motor is essentially the same as an n/a motor. So, if by high maintenance you mean that you'll have to rebuild or replace the turbo once or twice over the average 150-200k mile life of a regular daily driven street car, then I guess so...
I haven't yet seen a claimed high horsepower set up yet that could be consider "the best of both worlds" nor would I ever recommend one of these abominations for a daily driven street duty.
I contend that among built motors, including an appropriate cam, the phrase "the best of both worlds" applies more accurately to turbo motors than any other kind, because n/a, blown, and nitrous motors prefer a lot more cam than turbo motors do. When you're not in the boost, the turbos aren't really doing anything.
Here's another interesting, though significantly less important to me, fact: with a given cam turbo motors are going to get better gas mileage than than blower motors. With optimum cams, the turbo motor is going to be significantly more efficient than the blown motor.
People that choose to do so, have convinced themselves into living with compromise and in some cases fooled themselves into believing they’ve made no compromise at all.
The turbo-related compromises that I feel I'm living with include:
- the turbo piping required some creative plumbing to make my stock A/C work, which has a leak somewhere, but is difficult to detect. Once I figure it out, I will no longer consider this a compromise.
- low exhaust back pressure called for mufflers that are pretty loud, though I like a quiet and conservative sound. I will likely change the mufflers to something more conservative in the future.
- the powerband from 2000 to around 3200 RPM. The motor made 362 RWHP on the break-in pull without tuning and n/a (with a blocker plate in place of the turbo), though... So, it is not a dog at that RPM by any stretch. And, this is not where I'd be in the RPM band during any race. An easy compromise for me.
- the torque is excessive, and the turbo hits so hard it's difficult to keep control with 17" drag radials when boost is at 14 psi. So, I turn the boost down to something a little more street friendly. 8 psi and somewhere around 530rwhp is very comfortable and easy to control. I'm ashamed of compromising 230rwhp for more comfort and control. Spinning that knob to lower or raise the boost is such a PITA
It sure would be nicer if I had to swap pullies every time I wanted to change things up.
Now, in regard to your last comment, are you sure that YOU didn't just convince yourself that turbos are hell to live with so that you felt better about your decision to go with a PD blower on your Cougar?
Chris