LB7 Wastegate capacity

[Nick]

Curious if anyone has experience with how much N2O can be pushed through the stock LB7 charger/wastegate without experiencing significant boost creep?


I don't need a jet size, just a drag strip MPH or HP number where another wastegate was needed or the stock charger was oversped with the wastegate operational.

Any info would be appreciated :)

Thanks,

Nick

[Josh2002cc]

Nick I would say ask Wade from ATS how much he sprayed his stock charger on his old motor. I know his truck handled alot just from talking to him about it.

[Fingers]

IIRC the problem was/is a limit with the waste gate actuator. Don't recall if it was the stroke, response or what.

[Ridge_Runner_Diesel]

Drop it to 22-24 psi,

With a .075 jet I saw over 30 psi........):h

I was gonna throw the .102 jet at it but I had to drive the truck home, it was worth 6-7 tenths though, dropped me from 12.66 on fuel to 12.00.

Use at your own risk or things could go BOOM !!!!

;)

[Nick]

Thanks for the responses guys. They're helpful.


Tony, did you lower the boost to 22-24 so you could see the boost pick up in time to get out of it or do you believe the added pressure on the waste gate allowed it to open further and let you squeeze it harder?

Again, thanks.

Nick

[Ridge_Runner_Diesel]

Thanks for the responses guys. They're helpful.


Tony, did you lower the boost to 22-24 so you could see the boost pick up in time to get out of it or do you believe the added pressure on the waste gate allowed it to open further and let you squeeze it harder?

Again, thanks.

Nick

The first time I sprayed it I lowered the boost to 25 PSI, I have a Banks Big Head so it may be a lil' different then a stock waste gate.

IIRC when the N20 hits it does kick the boost up quickly due to driving the charger harder, so you need to valve it more safely with a lower psi setting at the outset.

If you run a stock gate then use a PPE or Kennedy boost valve to keep it in check, with a big head you have to manually drop it down and then add a crack pipe to run fuel only and play with the orifice size to get the right boost levels.

:thumb:

[Nick]

Thank you for the helpful and informative post :)

Urge to increase cylinder pressure rising


):h