n_brio

I have been serching but i have not found anything use full.

sl1500 kit

with restrictor = 7 psi
how big diameter on the hole to make? = 10 psi
how big diameter on the hole to make? = 13 psi
how many psi without the restrictor?

on a ls2, m6 , cr:10, 1 7/8 headers och baby blower cam.

MARSC6

I'm seeing about 14psi no restrictor on a stock LS2 with headers.

robertaj

its all custom... in fact if i take my air filter off i can see the plate and clearly written on it "custom" and the plate is dremeled out to a specific size so I'm not sure there is a clear answer

MARSC6

All kits should be the same size. There was nothing like that on my plate when I still had it.

robertaj

interesting... well maybe i should back up. I don't have the stock kit. I have added meth and turned up the boost from the stock 7psi so they had to open up the plate a bit but it isnt removed all the way.


btw does anyone know what size the hose clamp holding the air filter onto the supercharger is? I apparently broke mine

Unreal

Trial and error. Boost isn't set by pulley restrictor, but those along with cam, headers, motor, etc. So a 3.25 pulley and X.XX" inch restrictor could be 10psi on one car and 6psi on another. So there is no solid answer to that question.

Pitufina

Doug mentioned to me that every 1/16 removed from the inside diameter is aprox 1 psi. As Unreal said, I think every car is different because I've seen numbers all over the place on vehicles with full exhaust and cammed and with the restrictor untouched. At least that's what some owners say.

DOUG @ ECS

All well said guys. Although the part is very basic, getting it sized just right took a lot of trial and error. Each build will be different, cam specs etc etc, as said before, roughly 1/16" is about a pound of boost increase.

Impulse20098

I have the restrictor still in and have lg pro long tubes (1 7/8") on a ls3 and make 10 psi.

chuntington101

Doug, in theory you should be able to estimate the power output with the restrictor plate size. After all the restrictor plate will become the limiting Factor is the system and will not limit the boost pressure but the volume of air into the engine.

This technique has been used for years and years in Motorsport to give a level playing field. For example the WRC boys could run their engine a at over 45psi through a 34mm restrictor (it was not a plate but a lovely bell mouth that actually helped get the air over supersonic speeds to maximise airflow) but that was only at lowing rpm as the restrictor soon became the bottle neck in the system.

I say an estimate of power as some setups may be more 'efficient' and use the said volume of air to make more power.