Unlike all other +General Motors "tuners" offering horsepower upgrade for +Tadge Juechter 's "love child" flagship, C7 Z06 (as well as the base Stingray), Reese Callaway chooses to take the SAE certified approach for claiming the horsepower added to the LT4 supercharged turd. An inquiring mind would ask WHY? Of course the Corvette sheep will not ask but this is a given...
So what is up with that "SAE certified" horsepower instead of the usual dyno run? Is this any better or more meaningful than otherwise? Not exactly and in fact, it is considerably more misleading than the rear wheel hp claims (especially those with hood up and plenty of fan induced air circulation early in the morning).
Right off the bat, the engine dyno numbers will be higher than at the wheels, this is a given. Then there is a matter of consistency with the GM published numbers, eliminating any possibility for real life power loss and even less gain than currently claimed.
But... there is another twist here, the fact that the SAE standard for American cars, J1349 was modified several years ago by the fine folks running this organization, requiring car manufacturer, while the motor is tested on engine dyno to hook up the hydraulic power steering. Of course, it just happened that the newest generation of Corvette is the first one to use ELECTRIC power steering (overheating at will but nevertheless). The use of electric power steering allows GM to squeeze a few more ponies out of both, LT1 and LT4 engines. Given the connection with GM, good ole Reese would have to be stupid not to jump on the SAE certification bandwagon, his numbers look better and since nobody really knows what the actual drivetrain loss is on the newest Corvette is, his numbers are absolutely safe from any peer scrutiny.
In reality, if anyone realized this part, it would be rather obvious that the stock LT1 and LT4 power gains are less than the numbers advertised. Technically, Tadge is not lying, he just "forgets" to explain this part to the unsuspecting buyers, making the claimed achievements so much more impressive. To be fair, creative marketing is certainly a strong point of Corvette team and Juechter himself.
Going back to Reese and his numbers, are they legitimate? Yes and no, they are legitimate on engine dyno but not sustainable in real life since as already mentioned, Reese is too lazy and greedy to improve anything at all in the car's cooling systems and more power is always more heat (fucking physics and energy conservation say so). Interestingly enough, Reese "forgot" to publish dyno charts, hopefully he will regain his memory soon and rectify this part since it would be very intersting to see what the power curve looks like.
As a funny sidenote and something the owners of previous generations of Corvette and competition like Viper and Mustang GT350R never have to worry about is the electric steering assist overheating and refusing to work. Yes, hydraulic power steering is parasitic but it is also considerably more full proof to sudden failure, like its electric counterpart. Thus, the owners of the C7 cars are able to feel the impacts of the extra power (this part is pretty funny).
Anyone with half a brain knows that it's RWHP that counts. This whole "SAE"/"Crank HP" thing is nonsense. A true sports car enthusiast wants to know how much hp/tq is being put to the ground when they press the gas pedal. Reese needs to post a "baseline" pull, and a "modified" pull for the numbers to have any meaning at all. Convenient that the dyno graphs are omitted. Why doesn't this type of misleading marketing surprise us? Well, because it seems to be a common theme with the C7. BTW, only 757hp? Really? That's only 107hp increase at the crank prior to the mod. Which means you are probably only getting about 80-90 at the wheels. How much is he charging for this oversized hair dryer again???? Pathetic. BTW, your "love child flagship" phrase at the start made me laugh out loud. Nice!!
ReplyDeleteWell stated:) The honest way for Reese would be to measure stock and then (the same) the modified car at the wheels and with hood shut, assuming he would not be fudging this part as well.
DeleteAs I've stated in the past, a hood up / fan on engine condition is the STANDARD for testing on a dyno. You have to quit insinuating that it's somehow a cheat. Seriously, a quick google search will confirm this.
DeleteFrom story - We sought out the highly accurate Mustang Chassis Dyno at Performance Turbo Motorsports (Belton, Texas).
PTM's normal test procedure calls for raising the hood, and positioning the external cooling fan roughly 6 feet in front of the bumper.
http://www.hotrod.com/features/0612phr-dyno-accuracy-testing/
Mack, you are clueless-as expected.
DeleteDid you actually read the story? Everywhere I look on the web shows that an open hood and fan is standard for dyno testing. You constantly imply that it's a cheat of some sort and that all cars should sit with their hoods closed and zero airflow on a dyno. I guess I'm just not seeing where you're coming from.
DeleteAs for Calloway, their "SAE testing", the shortcomings of the corvette, the issues that need to be fixed..... well we agree on all that.
Mack, report back when you spot cars driving with their hoods up and the fans standarized to operate at specific speed and size.
DeleteI can see putting a fan in front of the car on the dyno, but the hood should remain closed, just as it is driving down the road. Callaway seems to be pulling the wool over the eyes of his customers for $17,000!
DeleteWhy don't you report back to me when you see a car driving down the road at 50mph with its hood down but no air movement over, through, or around the car. So the problem appears to be that you don't like the idea of the hood up, not the fact that it's the industry standard when it comes to having a car on a dyno. Got it! :)
DeleteHey peter and lee let me know when you see a car driving down the road with no air flow thorough the radiator and the intercooler. Dumb shits.
ReplyDeleteYou are a clueless idiot but get published to demonstrate how dumb Corvette owners really are. Close the fucking hood and start blowing the fan at the car all you want you fucking tool. The latest Corvette piece of shit cannot circulate and extract air from engine compartment, it is already a fact and the reason for heat soak. What a fucking tool.
DeleteJust to be clear, I didn't actually weigh in on the whole "cooling fan" issue, so TJC you need to get your "shit straight" dumb shit!!! All I said, if you had even a grade four level of reading comprehension, is that publishing crank hp numbers is the stupidest most misleading means of demonstrating how "powerful" your car's engine is. Crank numbers don't mean shit, unless of course, you like to sit in your garage and rev your engine!!!! What does matter, is how much power/torque are put to the ground when you put your foot down. Internal frictional forces, parasitic loses through the transmission, differential, and wheel bearings make crank hp figures absolutely worthless, since all of these losses are unknown. So, dumbass, read my comment again, and prepare to discuss something I actually wrote.
ReplyDeleteHe is a dumb shit but this is not surprising.
DeleteOh, and one other thing. $17,000-$19,000 for an increase of 107 hp at the crank is the biggest fucking rip off I have ever heard of for a domestic automobile. Yes, upgrades for Ferraris, Lambos, and Porsches are often in this range for a similar increase, but the people who own those cars have money to burn, or at least they want everyone to think they do. In addition to my Gen V Viper GTS, and Honda S2000, I also own a modified 2008 WRX STi, that is currently putting out somewhere between 300-350 WHP/TQ, if I were to upgrade my stock turbo to a Blouche Dominator 3.0 turbo ($2000), change out my stock 565cc injectors for some 1000cc injectors ($600), and add an Aquamist meth spray kit ($800) + $2500 for installation and tune, I would easily see gains of 200+ hp/tq at the crank on my little 2.5 litre engine. Do the math. That's a 200+ hp/tq gain for under $6000.00!!!!!!! This could all be done in one day without any problem at all. If Reese can't get more than 107 hp at the crank out of a V8 for $17,000-$19,000 he should open a lawnmower repair business and leave the tuning to those people who actually know how to make power. For that kind of money, I could beef up my pistons/crank/rods, put in a badass cam, fit a front mount intercooler, and a Killer Bee tuned header, plus the mods I have already mentioned, with money left over, and be making 300-400 hp more than I am. In reality, I prefer to watch Reese separate the fools who bought the C7 from their money. They are easily parted.
ReplyDeleteI seriously doubt it is even 107 hp, outside of the SEA "test cell". Not until Callaway puts that piece of junk on the dyno, with hood closed after running a couple of laps in the summer temps. SAE tests specifies 77 degree ambient and zero humidity, thus, it means jack shit, just like those hero dyno runs (chassis and engine).
DeleteDefinitely would agree with not spending the 17 grand. I'd spend 2 at the lingenfelter and do the work myself. That would be keeping the same blower though. Which I would rather swap. But with the same blower you could get to the same number close enough not to spen anoth 15 grand. I don't understand how the 2.3 blower that Callaway installs is an oversized hair dryer. I wouldn't call a supercharger capable of over 800 hp an oversized hair dryer. Also I agree with crank hp rating is what it is. Plus it only makes sense to even state when your are actually dyno testing removed from the car. If you are measure wheel hp then you you guess and add "power train" loss that's just dumb. That's exactly what is is a guess. No 2 power trains lose the same amount of power. Not to mention to give a rating down to the single horsepower like "57" you might as well round it one way or other. To clarify the hood up. You don't get the same airflow as you do on the street with just the fan. That's why 90% of people dyno testing have the hood up. It helps to get the airflow numbers closer to normal.
ReplyDeleteThe reference to an "oversized hair dryer" was purposeful, and it was hoped that a reader would be able to interpret my analogy given the context of this blog, but if you insist, I will clarify it's meaning: placing a larger supercharger on a vehicle that is already suffering heavily from an inability to deal with heat soak is the equivalent of strapping an "oversized hair dryer" to it. The fact that the vehicle makes 800 hp is irrelevant if it is not sustainable, which it wouldn't be given the inherent flaws contained in the original design. There, have I made myself clear?
DeleteSure but your getting the heat soak problem because that 1.74 supercharger is spinning at 20,000 rpm. The 2.3 supercharger would provide more forced air at 16,000 rpm. Thus Less spinning require less cooling. And pretty sure the heat exchanger upgrades provides in package would solve that problem anyway. It isn't the design of the motor or the aero of the car causing the "heat soak" clear enough?
ReplyDelete