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Turbocharger Quick Spool Valves?

FellowTraveler

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I see a few here had installed quick spool valve on their 6.5td however at least one had stopped using it.

Aside the quick boost feature is the back pressure off boost that causing issues at cruising speeds, or?
 
I would install one again just for the exhaust sound alone. My MPG went up with it installed on the Suburban vs. just an ATT. As far as I know through the grapevine The QSV is still installed on the 1995 I sold.

The Quick Spool Valve was causing me some heating of the oil with 6.2 pistons where synthetic was required. Consider my summers hit 121 degrees. Note this means the QSV does hold some more heat in the engine. You could get fancy and have the computer control it aka open it up for cruise like it does with the vac controlled WG.

So with MPG increase I would say the back pressure was not a downside to the benefit of it. Recall the valve opens up with boost and completely gets out of the way where the smaller turbo's simply can't match the 1:1.1 boost ratio the ATT has.

After installing a 2400 RPM stall converter I no longer see a need for the QSV as the engine isn't under 2000 RPM where the larger turbo's just don't provide any boost. Sure it would help a little, but, not enough to be worth it on my setup.

Member "6.5L" has a manual trans so a high stall converter isn't an option for him.
 
Stock turbo spools up really quickly, I see measureable boost around 1800rpm on my current setup (see sig). Before this, it was spooling around 1600-1700rpm. I was running a hypertech tune at the time. Even with the addition of the 3 bar MAP sensor and frc-10, I was seeing it around there.
 
Stock turbo not even a consideration the Quick Spool Valve is for big turbos but lack control to open them while @ speed cruising so back pressure is not a problem.

The stock GM8 has 9 cm2 turbine housing so a 18 cm2 turbine housing is reduced to 9 cm2 w/quick boost valve creating and even bigger back pressure problem because of the large compressor at cruising speeds...............with the boost valve closed.
 
I know about that much for the bigger turbos. I didn't check your sig before. I'm still getting used to people on here, so I forget that you guys have some significant power upgrades done(Still used to the fb wackos). I had thought that you were talking about using one on a stock turbo
 
I know about that much for the bigger turbos. I didn't check your sig before. I'm still getting used to people on here, so I forget that you guys have some significant power upgrades done(Still used to the fb wackos). I had thought that you were talking about using one on a stock turbo
I was a nubee once upon a time too...........and I still forget things.
 
I'm considering a real Holset Super 40 which is 16 cm2 but with a bigger 18 cm2 turbine then use a quick spool valve w/o boost reference controlling it instead with the ECM PWM boost control circuit so valve remains open @ cruise.
 
I know about that much for the bigger turbos. I didn't check your sig before. I'm still getting used to people on here, so I forget that you guys have some significant power upgrades done(Still used to the fb wackos). I had thought that you were talking about using one on a stock turbo

Nick,
First off welcome. Second I am one of the commitable totally bonkers crazy ones on here: link. I send GMx turbos to the metal scrap yard rather than even sell the miserable things. IMO the GMx spools up when the starter is spinning... And is in the way as a heat building Asthma Attack after 2200 RPM.

Reference to what the OP's asking about:

Videos:
http://www.thetruckstop.us/forum/threads/att-videos.39789/#post-452501

Details of install:
http://www.thetruckstop.us/forum/threads/bd-quick-spool-valve-install-with-pics.36278/

http://www.thetruckstop.us/forum/threads/another-bd-quick-spool-valve-install-with-a-c.39716/
 
Jay -That's just mean.:grumpy: Some of us were happy to get any turbo instead of NA.

Ok, not really. I wish I could have a big boy turbo, specifically ATT. Just can't fit it. For any H1 owners, that came with a turbo stock- it might fit. NA hummer body is a little lower to the engine.

When my gm6 blows up I'm thinking about making a very intrusive doghouse to try fitting one.

With h1 gearing a QSV on ATT would help, but not needed. H1 needs top end help.

War Wagon, please sell the center mounts- hard to find and only option for some.
 
Jay -That's just mean.:grumpy: Some of us were happy to get any turbo instead of NA.

Ok, not really. I wish I could have a big boy turbo, specifically ATT. Just can't fit it. For any H1 owners, that came with a turbo stock- it might fit. NA hummer body is a little lower to the engine.

When my gm6 blows up I'm thinking about making a very intrusive doghouse to try fitting one.

With h1 gearing a QSV on ATT would help, but not needed. H1 needs top end help.

War Wagon, please sell the center mounts- hard to find and only option for some.

Speaking of... I watched the video of you driving your HUMMER through the wall. We need to get together and the resulting 2+ craziness would have an ATT stuffed on that HUMMER! You would have to make the redesigned doghouse available for production as I am sure it would be popular...
 
Well, I don't care about interior fancy stuff. Used ammo can is my new center glove box/ tcm&vssb holder. So no telling what that would take. It'll be a while before I can get to that project. So buried and little $.

And hey, that block wall had it coming!
 
Nick,
First off welcome. Second I am one of the commitable totally bonkers crazy ones on here: link. I send GMx turbos to the metal scrap yard rather than even sell the miserable things. IMO the GMx spools up when the starter is spinning... And is in the way as a heat building Asthma Attack after 2200 RPM.
Thanks. I've started coming on here for advice after having my truck for about a year and a half. There are only a few reputable guys out on fb that I reach out to, and they're not always available. I'm still fairly green with the 6.5, but I'm always willing to learn since I'd rather work on my truck than take it to a shop, since I can't afford to let a shop doing it, plus it's satisfying. I just want to make a daily that's got at least 220rwhp while sticking to a budget. Not trying to go all out here
 
So, in the end two installs of QSV didn't last long, was the move from them what I pointed out about back-pressure, or?

6.5L answered on here that he wanted to try new things best I recall.

If I hadn't sold it I would still be running a QSV and a high stall converter on it. Again it's still on it today best I can tell.

I just got tired of the s#it parts quality changing power steering pumps over and over and over and the rest of the dusted system, constant issues with that Suburban, and working on it to the point of ridiculousness. The AC on it never worked out here worth a damn so no love there. The bugs in fuel did not help and coming back on the hook for lift pump failures and PS seals blowing out just made us part ways. The fellow bought it said "Wow this thing really runs!"

As long and as hot as last summer was out here I am glad than damn thing is GONE.

So if I had a choice between the two I would go with a high stall converter because I like how much that wakes the engine up, NOW, when you slam the go pedal. The QSV is cheaper, less labor to install, and delivers results.

Did a brake stand with patch today and lit the rear up on take off... the QSV won't do that.
 
6.5L answered on here that he wanted to try new things best I recall.

If I hadn't sold it I would still be running a QSV and a high stall converter on it. Again it's still on it today best I can tell.

I just got tired of the s#it parts quality changing power steering pumps over and over and over and the rest of the dusted system, constant issues with that Suburban, and working on it to the point of ridiculousness. The AC on it never worked out here worth a damn so no love there. The bugs in fuel did not help and coming back on the hook for lift pump failures and PS seals blowing out just made us part ways. The fellow bought it said "Wow this thing really runs!"

As long and as hot as last summer was out here I am glad than damn thing is GONE.

So if I had a choice between the two I would go with a high stall converter because I like how much that wakes the engine up, NOW, when you slam the go pedal. The QSV is cheaper, less labor to install, and delivers results.

Did a brake stand with patch today and lit the rear up on take off... the QSV won't do that.

So, no numbers on back/drive pressure @ cruise OK. I see lots of info that the QSV is great for racing however little or no feedback on a daily driver and was hoping for some input by those who have done it and had info in back/drive pressures @ cruise.
 
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