5psi from SC on stock pulley with Headers and no cat?

[geohil]

Just ordered one....

Had another thought while chatting here. I do remember someone leaking boost at the fuel injector. If the 0-rings are not seated properly or cracked boost can escape. Good news is that one can be tested with the carb cleaner trick, but the chemical in that could harden the rubber ring.

 

[05SVRACER]

Just ordered one....

Had another thought while chatting here. I do remember someone leaking boost at the fuel injector. If the 0-rings are not seated properly or cracked boost can escape. Good news is that one can be tested with the carb cleaner trick, but the chemical in that could harden the rubber ring.

The 7th Injector?

 

[geohil]

No - I'm talking a leak from your primary 6 injectors. I had to do some digging to find the article but I think this is it:
Whats your boost on 3.4 supercharger with differnt sized pulleys? - CustomTacos.com Forum

 

[05SVRACER]

No - I'm talking a leak from your primary 6 injectors. I had to do some digging to find the article but I think this is it:
Whats your boost on 3.4 supercharger with differnt sized pulleys? - CustomTacos.com Forum

Hmmmm that'll be a ***** to get to...

Got off then phone with Gadget a bit ago...he was saying because its absolute pressure, being at 1000 feet with the truck off was normal.

Anyone ever pay attention to the boost reading and or discrepancy with a boost gauge?

 

[05SVRACER]

Per the video you posted I vaccum tested the bypass valve. Held at 20 with no drop. Also pulled the line off the boost port and tested it to make sure I didn't have a leak going to the pcu or the boost gauge. None there either, BTW the gauge was dead on with what my bleeder pump was saying. Checked for dusting too, there was a tiny bit on the underside of the nose cone where the pulley goes on. The unfinished aluminum part, and the same in the vaccum diagram on the hood. Think that is mainly from a new belt when I installed the sc. Cleaned it off and I'll keep an eye on it. But, I don't have a problem with bleeding off. Just jumping to a little over 4# on wot then going up to a tad over 5 like in the picture I posted.

If I have no leak from the bypass valve, that means everything is good there I take it. And no leak going to the gauge. Sprayed around the passenger side fuel rail/injectors. Can't really get to the ones under the sc. But they were a refurb SRT from LCE with all new gaskets.

Anything that I'm missing?

 

[05SVRACER]

So, put little zip ties on all the boost fittings behind the SC. Now at idle I'm a little over 20 in/Hg. So, apparantly there was a bit of a vaccum leak. Boost is still at 5psi though. That may be just fine, one more thing to check though...bypass valve adjustment.

What do I look for with the adjustment on the bypass valve? I know it holds vaccum, but want to make sure adjustment is correct...

 

[djskorch]

Im not sure what is going on with your guys sc setup or if maybe in just lucky but I have a 1st gen with a static tensioner on the stock 2.34?" pulley and I get 7-9 psi with the airbox elbow removed, trd catback and deckplate mod. I am at 2200ish ft above sea level and have tested on multiple boost gauges to make sure its not just my gauge.

When I had the underdrive pulley (2.67?") I was getting around 5psi.

 

[05SVRACER]

Im not sure what is going on with your guys sc setup or if maybe in just lucky but I have a 1st gen with a static tensioner on the stock 2.34?" pulley and I get 7-9 psi with the airbox elbow removed, trd catback and deckplate mod. I am at 2200ish ft above sea level and have tested on multiple boost gauges to make sure its not just my gauge.

When I had the underdrive pulley (2.67?") I was getting around 5psi.

Mine has the stock 2.34 on it. I'm at 1000 ft I have TRD headers, no cat, and Borla "cat-back"...

 

[05SVRACER]

Well the buddy at work (a tech mind you) was who I tossed the keys to after I fixed the vacuum peak and told to see what boost readings were. He said 5...And he needs glasses. It builds 6 on wot and gains to 7 in high rpm. Now that the urd pcu sees thecorrect boost level, the truck is 10 times smoother. Now to start tuning and the smaller pulley!

Thanks for all the help guys!