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Need help: Boost falling off

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Old 04-20-2019, 12:08 PM
  #21  
Corvette4ever
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Originally Posted by BooSSted
Messaged BTR on proper push rod lengths, i just think the issue would have showed up before
Don't think BTR's answer is going to be accurate. IMO, this questions should go to the guy who installed your cylinder heads. He should have measured the correct pushrod length to achieve the correct lifter pre-load

Every combo is different. I was recommended by the vendor to use stock length pushrods (7.85"), but I ended up with 7.8" pushrods
Old 04-20-2019, 01:30 PM
  #22  
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Originally Posted by Corvette4ever
Don't think BTR's answer is going to be accurate. IMO, this questions should go to the guy who installed your cylinder heads. He should have measured the correct pushrod length to achieve the correct lifter pre-load

Every combo is different. I was recommended by the vendor to use stock length pushrods (7.85"), but I ended up with 7.8" pushrods
What's measured to test the correct lifter pre-load? That's interesting because most of these shops when you order a cam kit etc they typically order and have everything in for the install. I doubt this is done correctly often.
Old 04-20-2019, 02:06 PM
  #23  
douglee25
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Where are you referencing boost?
Old 04-20-2019, 03:58 PM
  #24  
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Originally Posted by douglee25
Where are you referencing boost?
On manifold line which lowside and meth are referenced from.
Old 04-20-2019, 04:28 PM
  #25  
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Originally Posted by BooSSted
On manifold line which lowside and meth are referenced from.
Have you ran a dedicated boost line direct to the manifold?
Old 04-20-2019, 06:00 PM
  #26  
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Originally Posted by douglee25
Have you ran a dedicated boost line direct to the manifold?
No additional boost lines were ran, using the stock gauge and line ran for hobbs switch and meth.
Old 04-21-2019, 04:37 PM
  #27  
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Are these big red race BOV's adjustable at all to anyone's knowledge?
Old 04-21-2019, 05:40 PM
  #28  
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Originally Posted by BooSSted
Are these big red race BOV's adjustable at all to anyone's knowledge?
yes you can adjust how wide they open the valve (if you talking about the older version)
Old 04-21-2019, 05:58 PM
  #29  
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Originally Posted by black_c7
yes you can adjust how wide they open the valve (if you talking about the older version)
Just reading various threads online and quite a few people had issues with the BOVs. I mean if its not seeing vac, it should be holding closed.
Old 04-21-2019, 06:17 PM
  #30  
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Originally Posted by BooSSted
Just reading various threads online and quite a few people had issues with the BOVs. I mean if its not seeing vac, it should be holding closed.
check the seal inside the bov, maybe it causing the problem
Old 04-24-2019, 05:40 PM
  #31  
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Any updates on a solution to OPs problem?
Old 04-24-2019, 08:06 PM
  #32  
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Not yet, leak down test be wrapped up by weeks end which will tell if its something internal. I'll update as info comes...
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Old 06-07-2019, 11:28 PM
  #33  
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Quick check in and update on this **** show...

Pressure tested entire system, addressed 1 minor leak on MAP sensor...

Adjusted and tripple checked BOV, even switch to another race PC BOV... Good to go.

Purchased new tensioner and mounting plate as the original one didn't free spin the best.

Leakdown test came back good with no issues internally.

Springs looked good when it was apart again, cant see BTR springs failing in under 1000 miles.

Checked throttle position, its not closing at all...

As we fix minor things an improve air flow the issue is becoming more pronounced eariler in RPM band, as im hitting boost eariler. Now it's nosing over at 5200K. Don't know wtf else to do.

Looking at replacing the intercooler, maybe something is jacked up inside? Seeing 4-6# difference preintercooler to manifold. But it still falls on its face at, boost wise; the rpms will still climb. Running gated HD green belt, thinking of switching to something softer, maybe this **** isn't gripping. What other belts are good?

Last edited by BooSSted; 06-07-2019 at 11:29 PM.
Old 06-09-2019, 05:46 PM
  #34  
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Originally Posted by BooSSted
Quick check in and update on this **** show...

Pressure tested entire system, addressed 1 minor leak on MAP sensor...

Adjusted and tripple checked BOV, even switch to another race PC BOV... Good to go.

Purchased new tensioner and mounting plate as the original one didn't free spin the best.

Leakdown test came back good with no issues internally.

Springs looked good when it was apart again, cant see BTR springs failing in under 1000 miles.

Checked throttle position, its not closing at all...

As we fix minor things an improve air flow the issue is becoming more pronounced eariler in RPM band, as im hitting boost eariler. Now it's nosing over at 5200K. Don't know wtf else to do.

Looking at replacing the intercooler, maybe something is jacked up inside? Seeing 4-6# difference preintercooler to manifold. But it still falls on its face at, boost wise; the rpms will still climb. Running gated HD green belt, thinking of switching to something softer, maybe this **** isn't gripping. What other belts are good?
Remove blower inlet elbow, filter and go for a quick test to rule out inlet restriction.
Old 06-09-2019, 05:53 PM
  #35  
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Originally Posted by rflow306
Remove blower inlet elbow, filter and go for a quick test to rule out inlet restriction.
Yes sir, removed elbow and filter just got that. Trying the procharger bell/screen so no restrictions there on inlet...

Old 06-09-2019, 07:39 PM
  #36  
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Have you tried a Gates RPM belt yet?
Old 06-09-2019, 08:33 PM
  #37  
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Originally Posted by Patriot Six
Have you tried a Gates RPM belt yet?
No sir, i read they dont like to give... was debating on going the other way in terms of something softer that may grip better. The Gates HD green belts is what ive been using. The pulley was getting crazy hot but no dust, shavings etc indicating slip. And moving to 10 rib, boost should be around 19-20# ..

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Old 06-11-2019, 10:16 PM
  #38  
black_c7
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Ditch that **** belt bro get an rpm belt, before i used to think green is the best, but not after i trierthe rpm

the hd will have too much stretch and will keep breaking, if the rpm belt is set probably you will forget about any issue that can be caused by the belt!
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Old 06-12-2019, 12:26 PM
  #39  
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That's next with a griptech pulley. Actually going in a different direction at this point with A2W. But with the GT pulley, RPM belt i figure this issue will finally be over. Thanks fellas!
Old 06-17-2019, 09:01 PM
  #40  
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You get it dialed in?


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