should i get boost at idle when i rev? should the bov go?

[farmerz24]

hi guys, just got my t3 (.82ar) 60-1 turbo installed on my 3100. tried revving it in neutral and i cant get any boost to show on the guage nor will the BOV go. obviously if there is no boost the bov wont work, but shouldnt i be seeing at least 1 psi when revving or do i just need to load the motor for this? just wondering what everyone else's experiences were as my friend has a srt4 and his will activate at idle.

anyways, what do you think? maybe i have a boost leak, however im sure i dont as i triplechecked all the connections.

[Doubt_Incarnate]

make sure you dont have any exhaust leaks before the turbo either. turbos are just metal unless there is hot exhaust gasses spinning them. you have an oil line? and there is oil for sure getting there?

[RebelGT]

is the gauge showing vacuum change?

[germ]

no, you shouldnt see boost at idle or revving the engine, only under load as you suspected.

if you have a manual tranny, i assume you can build some boost, but if you have an auto tranny, nope, no boost

[RedZMonte]

Ummm.. No you should definatly not see any boost in neutral. You only build boost when the engine has a load on it. the reason Turbo autos kick ass is because you can power brake it from a stop and build boost before you launch. My TGP hit full boost (10psi) before i even left the line. Kicked ass! and my monte has a hauss turbo on it so it doesn't hit full boost till ~3800-4000 rpms, but being an auto i only have to worry about spooling it once. Once its spooled it never dips out of boost untill i let off.

Turbo 5speeds can add a "2 step" aka "Chatter Box" so it will limit the RPM's, add timing and what not so you can build boost with the clutch in while getting readly to launch. cool to watch, they make some wicked backfires!

S

[farmerz24]

ya the guage is showing 20 vac at idle and it goes to 0 when revved just wont build boost. my buddies srt 4 shows a few psi when revved maybe its just cause he has a smaller turbo the BOV does activate so i was just wondering what everyone elses experiences were.

anyways, ill road test this weekend hopefuly and let you guys know.

[Syn]

a srt 4 i've seen do it but i am sure there turbo is smaller, my saturn needed a load to build boost i was hitting full boost around 3k 10psi. but it would build anything in neutral. the reason it can't is cause theres less of load on the engine obviously, and doesn't have to work as hard to reach the higher rpms

[Guest]

Yep, 99% of cars out there will not see boost in a nuetral rev.

However I did have one car an Escort that showed 5 PSIG in a nuetral rev. I was trying to fix up someone elses piss poor install, and had the boost controller turned all the way to full boost, when we thought it was turned all the way down. Pretty cool when you see 5 PSIG in nuetral.

ALso the BOV should still operate, in a nuetral rev, and may even vent some excess pressure, it just won't be the same as under load with a higher boost pressure.

Case in point the 3400 turbo that I built for JuLu, the bov will still vent in a nuetral rev, but not loud and you really have to listen for it. but once even just a few PSI is built, it's quite loud and music to the ears.

The way the BOV is desined and even connected can have an effect on how it functions as well. SOme BOVs, whihc are generally used more as bypass valves are open at idel due to the high vaccum present at idle. 1st gen Talon/Eclipse bypass valves are like this. I'm attepmting to modify one that stays closed at idle.

[Kohburn]

with a 60-1 turbo on a 3100 you should see no boost
I have a smaller turbo (T04E-57) on a 3.4dohc and pull about 3psi at 6500rpm out of gear.. its about as small a turbo as i can go on the dohc.. a 60-1 is ideal