Quote:
Originally Posted by Evan Smith
All,
Why should blower speed be montored or limited? Turbo impeller rpm/boost pressure is not monitored or limited in turbo applications, or current blower applications, nor is rpm monitored or limited in a naturally aspirated combination. There is certainly power to be had by revving a n/a engine higher than stock, so why is that allowed? The blower is a part of the engine, and if it can legally be manipulated within the rules for better performance than so be it. Most of you run underdrive pulleys for your alternator, why? Because there is power to be had. So, the same rule should be in place for blowers.
You are all playing tech director and rule maker without taking into consideration your own combinations. If you are going to comment then look at the whole, not just your own agenda. Of course, everyone is worried that a blower car will dominate, but it's just a car with an engine and the AHFS will take care of it if it is underrated. Yes, NHRA will have to monitor performance for runaway combinations, just as they do or don't do with other engines.
Please look at both sides of the fence before commenting, that is all I ask.
Evan
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And the turbo cars should have the same treatment. In essence, a turbo or blower increases cylinder pressure just as placing pop-up pistons in a N/A engine. If the factory intends for a N/A engine to have 10.0:1 compression then that is what it is by design; i.e., piston configuration, bore / stroke and combustion chamber size. It is fixed and if NHRA doesn't receive altered specification, it will remain unchanged and HP will be dependant on those fixed variables.
Obviously these factors still apply to a boosted application. Furthermore, the factory intends for a turbo or blower to provide a set amount of pressure to the cylinders. That figure, just as the N/A engine, should not be altered.
SCCA racing in the 80's was dominated by Chrysler FWD turbo cars. Eventually, SCCA got smart and required turbo racers to install an SCCA supplied / sealed waste-gate to the inlet befor each race. Boost was regulated to factory or maybe even SCCA specifications. As I once raced an A/FS '87 Shelby Daytona Z (2.2L 4 cyl Turbo II), I know the factory peak boost was factory specified and electronically controlled via the ECU & waste gate to 14 PSI peak. By passing the ECU to the waste gate is simple and I typically ran 20-22 PSI boost through the factory inter-cooler for approximately 275 HP or 125 HP per litre.
Danny Gracia was once asked about blown vehicles in Stock. I believe it was in reference to the Ford Lighning trucks. Now this is second hand information but what was related to me was "pulleys will remain OEM size". At the time I thought it was silly as the turbo cars did not receive the same consideration.
I'm sure all of this will be nill as Rousch & Ford will offer high altitude pulley options.
And I am all for the boosted cars and trucks in S/SS as this is what is offered. I'm just saying they need there own paragraph or two in the rule book.