Twin 67/66 Lazy...Help
07-17-2020 | 11:34 AM
#21
Depends on the rest of the setup and if you know what to listen for. I think we assume a lot about owners, some may have little to no experience. I don't hear diddly out of mine and they are both vented. They are 4 inches from 2 open 3" dumps however! They could be "cracked" open or not seated properly in the valve cup. I've seen the valve cups not installed numerous times as well. Yet to see one of the cheapie gates that sealed well out of the box, some much worse than others. Sounds like he used good parts, so hopefully that isn't the case. Also if there's say a 16th gap all around, the sound will never change. "Leaky" will just sounds "normal". Just something good to verify IMO.
It is open at idle which I have not seen before on a BOV...Is that ok?
Any ideas on how to seal it? It is a V band style connection.
07-17-2020 | 12:06 PM
#22
The reason I asked about the turbos was they are a DBB turbo (or so they say) however before I installed them I try spinning by hand and they only spin a few rotation. I have seen other DBB turbos when you spin them they spin very freely. These acted more like a JB then BB.
07-17-2020 | 12:25 PM
#23
BOV should be closed at idle with a turbo car. Basically means your engine is pulling enough VAC to open it at idle. Should have just enough spring to stay closed at idle. Spring in it needs to be shimmed or stepped up in pressure. If it's a speed density setup, it's not going to really "hurt" anything. And shouldn't be the the cause of your leak alone. But no reason to suck in unfiltered oil with a turbo.
You could setup your phone to take a video of it during a quick pull? Should be pretty easy to see?
You could setup your phone to take a video of it during a quick pull? Should be pretty easy to see?
07-17-2020 | 12:30 PM
#24
BOV should be closed at idle with a turbo car. Basically means your engine is pulling enough VAC to open it at idle. Should have just enough spring to stay closed at idle. Spring in it needs to be shimmed or stepped up in pressure. If it's a speed density setup, it's not going to really "hurt" anything. And shouldn't be the the cause of your leak alone. But no reason to suck in unfiltered oil with a turbo.
You could setup your phone to take a video of it during a quick pull? Should be pretty easy to see?
You could setup your phone to take a video of it during a quick pull? Should be pretty easy to see?
07-17-2020 | 02:57 PM
#25
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From: Norn Iron
I would say the BOV open at idle would be a little unusual, and certainly worth investigating.
But certainly a proper ball bearing turbo should spin very freely, and on shutdown they tend to keep spinning for some time.
But certainly a proper ball bearing turbo should spin very freely, and on shutdown they tend to keep spinning for some time.
07-17-2020 | 03:14 PM
#26
Journal bearing stuff should light almost instantly with that setup as well. Still say there's some sort of "big" problem. Stinks if you paid for BB an ddin't get it though! Viren is known for pretty killer customer service. Call him up and ask. I'm sure if the wrong units were sent, he'd fix the problem.
Last edited by Forcefed86; 07-17-2020 at 03:24 PM.
07-17-2020 | 03:45 PM
#27
Journal bearing stuff should light almost instantly with that setup as well. Still say there's some sort of "big" problem. Stinks if you paid for BB an ddin't get it though! Viren is known for pretty killer customer service. Call him up and ask. I'm sure if the wrong units were sent, he'd fix the problem.
On a previous Camaro i installed the AGP twin kit which used T3 57/57 on a bone stock LS3, never had an issue the turbos came on strong and fast.
I'm really at a lose on this one...
07-17-2020 | 04:00 PM
#28
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From: Norn Iron
If you can feel the turbos impeller/shaft, the difference between a JB and BB is night and day so should be obvious.
But check or get rid of that BOV to try. ( and plug the hole if you do of course )
But check or get rid of that BOV to try. ( and plug the hole if you do of course )
07-17-2020 | 04:19 PM
#29
I thought the same thing, before I installed the turbos I spun the shaft and it just didn't feel like a DBB. As for the BOV any suggestion on plugging the hole?
07-17-2020 | 04:23 PM
#30
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From: Norn Iron
Well I cant see what you have or anything in order to suggest.
But surely it cant be that difficult ?
or at least take it apart to inspect if it is even capable of sealing. If it can physically close on its own and there is some spring pressure on it, just apply a boost line to the top, no vac and see if that makes a difference
But surely it cant be that difficult ?
or at least take it apart to inspect if it is even capable of sealing. If it can physically close on its own and there is some spring pressure on it, just apply a boost line to the top, no vac and see if that makes a difference
07-17-2020 | 04:39 PM
#31
Well I cant see what you have or anything in order to suggest.
But surely it cant be that difficult ?
or at least take it apart to inspect if it is even capable of sealing. If it can physically close on its own and there is some spring pressure on it, just apply a boost line to the top, no vac and see if that makes a difference
But surely it cant be that difficult ?
or at least take it apart to inspect if it is even capable of sealing. If it can physically close on its own and there is some spring pressure on it, just apply a boost line to the top, no vac and see if that makes a difference
07-17-2020 | 10:14 PM
#34
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Having a similar issue with twin s366 .91ar on a manual 5.3. Full boost in the low 6000rpm range. I had some weak 1.3psi springs in the gates. It was definitely leaking a bit at idle. I was still able to target almost 30psi but wasn't reaching that till 62-6300rpm. I just put in some 12 psi springs this morning to see if that may help spool.
07-17-2020 | 11:22 PM
#35
.96 ar on the hotside is kind of big for twins. I run on3 70/68 with .68 hot side ( originally had the .96 hot side ) and my turbos were laggy with the .96. I change to the .68 ar and the difference was night and day. I have power at 3000 rpm now, before it was coming in at 4000+
Id look into that.
Id look into that.
07-18-2020 | 10:45 AM
#36
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.96 ar on the hotside is kind of big for twins. I run on3 70/68 with .68 hot side ( originally had the .96 hot side ) and my turbos were laggy with the .96. I change to the .68 ar and the difference was night and day. I have power at 3000 rpm now, before it was coming in at 4000+
Id look into that.
Id look into that.
07-19-2020 | 12:35 PM
#37
My car makes 825whp at 5500 rpms i need stronger springs to make power past that. What i was saying is my car doesnt feel laggy anymore after going from the .96 ar to the .68 ar housings. My car runs 17 PSI w/ co2 boost controller.
07-19-2020 | 12:43 PM
#38
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what’s an indicator that springs are weaker? I have btr cam and btr dual springs but my power drop off is rough. Anyway I can test this spring situation ?
07-19-2020 | 08:07 PM
#39
Im pretty sure my springs are just fatigued and the valves are staying open at higher boost levels. My dyno sheet/power band is like strait up until about 5400-5600 rpm and then just falls on its face. Its not the tune. I bet if I could rev all the way to 6500 I would easily be close to 900 whp.
I dont plan on changing springs anytime soon, my car is just a street/daily/full interior/AC car.
I dont plan on changing springs anytime soon, my car is just a street/daily/full interior/AC car.