Quote:
Originally Posted by olddog
Experts on here have done some pretty fair tests and proven that a carb will make more power than EFI. I do not understand why, but I do not question their attempt to do a fair test.
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Volumetric Efficiency increases as air velocity increases, as engine RPM increases; and for some mythical, magical reason, carbs allow air to flow through the intake manifold faster than EFI does at lower MAPs, and higher RPM's...
I've likened it to watering your plants with a spray bottle, versus a watering can. If the plants need a low to moderate amount of water, the spray bottle does a better job of efficiently (and economically) moistening the soil, and increasing the humidity in the immediate area of the plant; but when the plant needs a LOT of water, even a super-awesome computer just can't pump that spray bottle lever fast enough to deliver a volume of air/water mixture at a velocity necessary to really soak the soil... When high-speed delivery is the goal, old-school watering cans rule...
However- Who cares about peak HP? By and large, EFI allows better volumetric efficiency at lower and mid-level RPM's (where it counts on a true multi-purpose engine) and Olddog has already pointed out the benefits of EFI for track use (especially autocross)
Peak HP is for bench-racers, and carbs are for guys (like me) who enjoy fiddling with their tune all the time.
For all the "just get in it and drive" types, EFI is the most rational option.
Regarding the question of Backdraft versus SPF- My only opinion there is that Superformance bodies, while still not perfect representations of csx3000 cars, still look closer to the mark than BDR bodies do (if that's important)
But, BDR's fatter rear fenders serve a purpose- Their cars are designed to wear wider, modern Z-rated tires, and to go racing-
JMHO, but if racing and raw performance numbers is more important than styling/originality, then BDR makes for a better foundation to build a more modern racecar. (unless you are considering Vintage racing classes, where originality in chassis and suspension design are important considerations, which would swing things back toward SPF...)
Regarding BDR versus Factory Five- for a race/performance oriented car, a FF is a great option to consider- Like them or hate them- FF's chassis design is the most rigid of the bunch.
The cost of a FF kit, combined with the cost of putting it together is right in line with the cost of a delivered BDR roller (every car has to be put together by SOMEONE, so you can't really escape the assembly cost)
Regarding the "show car" appearance... Pfft- You can't win that game, so why even play?
For every guy out there that hates your car because "a Cobra shouldn't have headrests, or an EFI Coyote in it" There will be another guy who looks at it and appreciates the workmanship that went into making it go together...
Kind of like the local guy out here in Az that put the mega-huge aluminum offshore V12 in his Kirkham. Purists hate it, practical hot rodders don't understand the cost-factor of all that effort, performance nuts don't understand what good a car is when it can only be driven at half-throttle... and in spite of all that- It's still one MEGA-cool machine.
Do your car, your way, work with your builder, and ignore the haters. That's the best advice anyone on here is going to give you.... The rest will all just be blathering and bloviating. (like I just did for half a page, hahaha
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