Wut
Dyno's can be set up do create these gains. It is a sales and marketing tool.
http://www.pencilgeek.org/2009/09/exposing-dyno-cheaters-how-the.html
6
Cold Air intakes: Why do we keep doing this shit?
- Thread starter mophisto
- Start date
Dyno's can be set up do create these gains. It is a sales and marketing tool.
http://www.pencilgeek.org/2009/09/exposing-dyno-cheaters-how-the.html
Pmanpop
Go Kart Champion
Funny how stage 2 dyno 200whp also haha. Like come on guys... I know dynos are different but dayummmmmmm
SnailPower
Autocross Newbie
I think you might get minimal HP gain with a CAI on a N/A engine as the air is going into the engine which is always good.
The fact that the F/I engines the air is basically going into the turbo which is so damn hot, I don't think the air going in will do enough in terms of making it much cooler to perform that much better. So yeah, your basically getting awesome noise for the F/I, vs the N/A your getting more HP but zero noise.
The fact that the F/I engines the air is basically going into the turbo which is so damn hot, I don't think the air going in will do enough in terms of making it much cooler to perform that much better. So yeah, your basically getting awesome noise for the F/I, vs the N/A your getting more HP but zero noise.
Years ago there was a guy in the turbo Mopar world named Gus Mahon. He had a fairly fast turbo minivan and an even faster turbo Acclaim. On both cars, he installed a large efficient FMIC. When doing so, the air filter location and whether it was "cold air" or not was irrelevant. So much so that he eventually settled on mounting cone filters directly to the compressor inlet. Made NO difference on a dyno or in his 1/4 mile times. He documented it all. Since then, I have always spent my $$ on cooling the post compressor charge air. More bang for your buck.
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Perhaps it's good to consider too regarding n/a engines, length tuning comes into play, being determined by which reflection and at what rpm you wish the intake tract to resonate. Not much of a consideration on forced induction as the resonate tuned lengths powerband is quite narrow, and depending on the reflection used, could be a very long intake runner. I don't think I've seen much resonate or exhaust scavenging work attempted on forced induction applications except perhaps the F1 fraternity.
But there we are again, recalling techniques that don't apply to much to the engines being discussed here....unles the engine being discussed has been tuned to the point that significant pressure drop in the intake tract has become a factor due to performance mods and is now a restriction...is that occurring on modified engines here? The intake becomes a restriction?
But there we are again, recalling techniques that don't apply to much to the engines being discussed here....unles the engine being discussed has been tuned to the point that significant pressure drop in the intake tract has become a factor due to performance mods and is now a restriction...is that occurring on modified engines here? The intake becomes a restriction?
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XGC75
Go Kart Champion
Actually go take a look at the gen 3 EA888. The exhaust manifold and turbine housing keep cylinders 1+2 and 3+4 separate almost all the way until hitting the turbine. It's not a dual-scroll turbo so I can only presume that has everything to do with exhaust gas scavenging. I don't know what kind of advantages it would bring to a turbocharged engine though. Maybe faster exhaust gas velocity and better spool up?
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I have come to realize anything and nearly everything on ECS website is horse dickery. They can't even get part numbers right for piss sakes.
Exhaust scavenging or resonate tuning and the spent charges momentum effect has a lot to do with an engines ability to generate a negative pressure signal, generated by the cylinder that has just fired, or the one prior to it, being timed so that just prior to the exhaust valve closing, that signal creates a negative pressure in the exhaust port at the seat area of exhaust valve port, adjacent to the chamber, which is the valve overlap phase. That negative pressure, cleans the chamber of spent gasses and assists in drawing in new intake charge. It's a naturally aspirated type of supercharging that can occur over a narrow rpm range, if the cam has enough overlap to allow both valves to be open enough at the same time. It's requires individual exhaust ports and header tubes to be tuned to a specific length and diameter, and the collector to to arrange the exits of each exhaust tube to be adjacent to the prior firing cylinder. It's why headers are designed the way they are on N/A engines. When the intake tract on a N/A engine is a tuned length runner as well, the combination of both tuned elements, exhaust and intake, gives a significant bumb in power...the engine is literally supercharging it's self within a narrow rpm range.
The key element beside designing both intake and exhaust tracts to create the tuned phase, is a cam with significant overlap, the time when both the intake and exhaust valves are open, and both the valves are off their seats enough to allow the pressure signals to move a good volume of charge. Turbocharging does this without such complex designs. It would be very wasteful and be inefficient on street turbo engines running those types of cams with much overlap...the charge would just blow right thru the chamber and out the open exhaust valve, without being ignited. Turbocharging is simple compared to high rpm, tuned n/a engine design, the manufacture doesn't need to do much revision to a n/a engine to convert it and the variable vane technology and computer controlled wastgates provide boost pressure over a broad rpm range, in a range that provide mid range power well...the range we accesss more than high rpm. Its why manufacturers use it. It's simple and effective at normal rpm ranges, not just high rpms. Our intakes and exhausts are mostly concerned with being big enough to get adequate charge in and out of the chamber without inducing restriction, not much resonate or pulse tuning occurring. Our cams don't have enough overlap to allow scavenging to occur. Street turbos don't need it as charge pressure and velocity are forced by the turbo anyway. Racing engine are another story. In past years when f1 was allowing four cylinders to make 1500 hp with huge turbos, they may have focused on tuning effects ad well as turbocharging.
The key element beside designing both intake and exhaust tracts to create the tuned phase, is a cam with significant overlap, the time when both the intake and exhaust valves are open, and both the valves are off their seats enough to allow the pressure signals to move a good volume of charge. Turbocharging does this without such complex designs. It would be very wasteful and be inefficient on street turbo engines running those types of cams with much overlap...the charge would just blow right thru the chamber and out the open exhaust valve, without being ignited. Turbocharging is simple compared to high rpm, tuned n/a engine design, the manufacture doesn't need to do much revision to a n/a engine to convert it and the variable vane technology and computer controlled wastgates provide boost pressure over a broad rpm range, in a range that provide mid range power well...the range we accesss more than high rpm. Its why manufacturers use it. It's simple and effective at normal rpm ranges, not just high rpms. Our intakes and exhausts are mostly concerned with being big enough to get adequate charge in and out of the chamber without inducing restriction, not much resonate or pulse tuning occurring. Our cams don't have enough overlap to allow scavenging to occur. Street turbos don't need it as charge pressure and velocity are forced by the turbo anyway. Racing engine are another story. In past years when f1 was allowing four cylinders to make 1500 hp with huge turbos, they may have focused on tuning effects ad well as turbocharging.
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ElectricEye
Autocross Newbie
I piss it the general direction of dynos.
Give me actual results of timed tests.
damagi123
Go Kart Champion
on point