boost leak,how much/long psi can yourcar hold?

[rab]

i have a few boost leaks , gong to try to fix them this week.
i would like to know how long you can hold the pressure in the system after you stop
pressurizing?
also how much psi's can your car hold?
i would like peoples personal experence, not what they heard about someones.
thank you

 

[unlmtdndeavor]

generally, i like to pressurize the system to near 10lbs over what i plan on running, just to be safe. there will be leaks like through the mbc that are tiny, which will cause the system not to hold pressure for an extended period of time

 

[rab]

how about for a system that does not use a mbc or has the hole blocked in the mbc for the boost leak test.
thanks

 

[rab]

anyone else?

 

[daren_p]

You should basically use as much pressure as you plan on boosting or a couple psi more. When all my leaks are fixed it probaby takes over a min to bleed down, haven't timed it exactly.

 

[kspharris]

I run 14 psi in my car but when I do a boost leak test I run it up to 20 psi. It instantly starts leaking down but very very slowly when there are no leaks. I haven't timed mine either but I would say about a min. like Daren P. I hope this helps and good luck, Keith.

 

[JayRolla]

Listen for any leaks. Fix those, then spray soapy water over all couplers and places you could have leaks. If you see bubbles fix those. If you get it so you dont see any bubbles in the soapy water you pretty much have it perfect. If you have a mbc remove it for the test.

 

[romeen]

i have a few boost leaks , gong to try to fix them this week.
i would like to know how long you can hold the pressure in the system after you stop
pressurizing?
also how much psi's can your car hold?
i would like peoples personal experence, not what they heard about someones.
thank you

It depends. On a cold motor you can get leakage past the piston rings which will cause it to bleed down faster. Also if the motor stopped with some of the intake/exhaust valves in overlap then it will bleed down fairly fast out through the exhaust although this doesn't happen frequently.

With my TB shaft seal leak and on a cold motor I typically lose 1 psi every couple seconds starting from about 20 psi. The rate of drop slows under 10 psi.