dump valve?

[DR.IAN]

Has anyone here put a dump valve on their lotus? I see one that they sale on lotusespritworld.com
What are the benifits? Do they increase power? Are thay just for the sound?

[DR.IAN]

Well, I guess that I can not put a dump valve on an 88...because there is no cooler on the turbo. Is it expensive to add a cooler or dump valve to an 88?

[GUY JOHNSON]

My 88' has a dump valve. It is not fully adjusted, but it does work well.


Guy

[ErnestM]

Dump Valves (Or Blow Off Valves) have two main benefits:

1. They keep the tubo spun up in between shifts and therefor avoid turbo "lag"

2. It keeps the pressure generated from shattering or weakining your impeller by giving it somewhere to go.

Technically there is no additional power, it just enables you to have consistent access to existing power.

Also, you can get either type of valve - vent to atmosphere or the recirculatory type that does not vent to atmosphere. My friend Karl has a BOV on his S4s and the sound bewteen shifts takes some getting used to.

ErnestM

[kylie]

So what is "Waste Gate Flutter" then? I have this light purring swoosh sound going through the gear changes and thought is was a std production feature in all turbos?

[lotusguy]

kylie said: So what is "Waste Gate Flutter" then? I have this light purring swoosh sound going through the gear changes and thought is was a std production feature in all turbos?

Kylie,

'Wastegate Flutter' is just as it sounds. On deceleration, especially under boost, at the instant of throttle closure there is a slight buildup of boost pressure which is just near the threshhold of where the wstegate opens, consequently the plunger on the wastegate opens slightly from this excess pressure and releases it. The pressure so closely matches the that required for the wastegate to open, that it doesn't open fully, but rather, opens/closes in a series of rapid sucessions. Adding a BOV or Dump valve (the terms are used interchangeably, but are really two distinct applications) will release this pressure before this threshold is reached eliminating the flutter. It also provides the additional benefit of not stalling the turbine and reduces the shockwaves which can weaken or damage the turbine blades. Happy Motoring! Jim '85TE