740 Turbo Volvo Electric Cutout #4

more videos showing the operation of the cutout

Category:

Autos & Vehicles

Tags:

• 740
• volvo
• turbo
• 744
• exhaust
• cutout

[terzer0]

@tororacer1 The RRP cutouts are same kind of junk as well... :I

[2turbotoyz]

@fmftrx300ex Actually scavenging does apply to a normally aspirated 4 stroke motor, referring to each exhaust pulse leaving a slight vacuum in its wake, helping to 'scavenge' exhaust. Even 4 stroke motors have reversion, when exhaust gas is sucked back in a valve. There is a patent for vented valves for 4 stroke motors to prevent this. perhaps there is a better term for this, but I have always heard it referred to that way. This is part of the reason equal length headers are nice to have.

[fmftrx300ex]

@pepene93 when you run a long tube header u get more low end torqshort pipes = top end in most cases in the case with a turbo u want the least amont of pessureafter theturbo, it will help spooling and cooling

[fmftrx300ex]

@2turbotoyz scavenging only apllys to 2 strokes because there back pressure forces the leaked fuel air mix back into the cylinder 4 strokes dont have air fuel going out the exhaust because they have valves not ports

[2turbotoyz]

Guys, its a turbo car. I know he doesnt say that here, look on turbobricks if you care. So backpressure is provided by the turbo, not the exhaust. After exhaust goes though a turbo, the exhaust pulses arent pulses anymore. Therefore scavenging does not apply. thelostartof knows what he is doing. I'm also sure he would rip some dyno runs if you pay for it, haha.

[pepene93]

i looked it up. and increasing the pipe diameter will slow down the exhaust, but not reducing additional pressure on it. and this may not pertain to you, but any back pressure is not always good. any engine will run best with open headers. however, in some cases, a little bit of back pressure can do more damage than a bit more. it only seem to relate to exhaust gas speed, not the pressure itself.

[tabamoura]

Only at low RPMs . It has to do with the nature of the flow being pulsating rather than a continuous flow. Decreasing the back pressure will cause the gases to slow down( velocity) .

I heard that this is not important in Forced induction engines. Look up " exhaust scavenging effect"

[tororacer1]

QTP cutouts are junk! i assume thats why you put RTV all over it is to try and make it seal? Get some RACE READY PERFORMANCE cutouts they have a lifetime warranty!

[pepene93]

ok, can somebody explain why decreasing exhaust backpressure decreases torque? it makes absolutely no sense to me.

[legendofassassins]

do you make that or did you buy that.