I got a good basemap burnt, so I try to build some boost and im not seeing any...

i go under the hood and rev it a little with my hand over the bov and i start feeling air come out of the bov...

i unplug its vaccume and the bov closes... the vaccume source has quite the suction at idle

i have its vaccume running off a T from the IM.

Any ideas on how to test the bov? or find the real problem if it might be something else?
Dan

 

the bov is under vacuum at idle so it will stay open a little. Its normal.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">the bov is under vacuum at idle so it will stay open a little. Its normal.</TD></TR></TABLE>

yeah i understand that... but it stays open when i rev up the engine, and i feel air coming out of the blow off valve and the boost gauge doesnt move.


this is a brand new setup and none of the parts, ie the turbo arnt tested... maybe the turbo is underboosting so the bov just stays open from lack of pressure?




Modified by welfarepc at 3:13 PM 8/19/2007

 

it's probably just sticky or something. take it off, clean it out and lube it up. Or to eliminate it entirely for testing, just loosen the mounting bolts and clamp a piece of thick rubber or something over the hole...dont over tighten it though, the long tabs on the DSM valves wont like that.

 

i changed the vaccume supply and cleaned it out a bit, seems to be working better but im still not building boost..

here is a pic


here is a short clip, does this sound right? (get ready fora rollercoaster ride)

http://video.tinypic.com/player.php?v=4m30hgi

 

sounds like an engine

 

i see a few things wrong with that setup....why arent you using real charge pipes instead of that mesh upper arm...secondly dont route the valve cover fitting back to the intake manifold unless you want to fry your piston rings.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by londoncivic &raquo;</TD></TR><TR><TD CLASS="quote">i see a few things wrong with that setup....why arent you using real charge pipes instead of that mesh upper arm...secondly dont route the valve cover fitting back to the intake manifold unless you want to fry your piston rings.</TD></TR></TABLE>

That upper hose is from a some 4g63 car. It will support whatever power he wants to make with this motor.

His valve cover vent is open to the air

As for your setup, welfarepc, you should get a real piece of vac line for your blow off valve to make it work correctly. I dont know if you took apart the dsm you got these parts from but you might remember the stock line is pretty thick which helps with response.

Also, on your intake manifold, the large middle port that goes down between the runners is going to the PCV valve. It's a good idea to take the end that is connected to the valve cover and reroute it onto the ground or into a catch can. Then you can use that big port for your wastegate or other things that need boost/vac. If the valve is stuck open it can also be a big boost leak.

What is the deal with the thin nylon line going from the wastegate? to the windshield? if thats your boost gauge line it should be coming off the intake manifold.

The best way to check for leaks is to rig up some fitting that can go on the inlet of your turbo that you can hook up compressed air to. That will pressurize everything all the way to your pistons. I usually do 5psi higher than the car will run.

 

good call on the catch can.
good call on the larger vac hose

the nylon tube is the boost gauge, i wanted to try and hook it up off the compressor to see if there was a difference in boost levels


can you even build boost by revving an engine like that ? im pretty sketched out about driving this thing around because ive never boosted a car before. wana try to make sure things will go as smooth as possible before i run this bitch up

 

i cant watch the video so im not sure how you are doing it. With a small turbo it should be no problem to floor it for a few seconds and make boost. Just put the gas down quickly and let off before redline or when you see some good boost

 

snap the throttle sharply, you will see it close.