S468 on with pics!

SuperDave4x4 said:
Faster than the T66?

I've never heard about these QSF's until now. Looks like must have for people streeting the larger turbos.
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The s468 turbo itself resulted in roughly 9 tenths quicker ets, maybe 1 tenth of that drop being weather difference if that. Saying that the truck feels faster then it did with just the s468 swap but that's likely because of the thicker midrange the truck now has.
 
kxhonda said:
Does the butterfly go on the volute that leads to the big side of the turbine or the small side of the turbine wheel?
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The butterfly is on the big side with the small side volute being the high velocity volute. I had no choice because of the wastegate tube interferring with the actuator. If you didn't have the tube you wouldn't have this problem. I've heard the idea of having the volute leading to the larger diameter of the wheel being the high velocity volute as being the best way to run it but have heard that people have tested both ways and noticed no difference. If I had a choice I would have run it with the big side as the high velocity volute.

High velocity volute = volute which the butterfly does not cover. It is the port where velocity is increased when the butterfly is closed.
 
I would think that the high volocity volute should be driving the big side also. Too bad you don't have the room to try it both ways.
 
Great assessment of the QSF Nick!

i really want one just for the more boost at cruising and lower egts, oh yeah spool up too.

I ve been trying to think of what all would need to be modded in a twin setup.

I think i can just get away with shortening the hotpipe? Anyone think sounds right or will i run into more problems?
 
NickTF said:
Things that had to happen to fit the flange.

I had to make a spacer for my down pipe which consisted of welding two s400 v-band flanges together to move my down pipe 1" farther back.
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Nick, why did the installation of this QSF result in the movement of your downpipe backwards 1"? Wouldn't it just result in moving the turbo towards the passenger side 3/4"?

Or was this change due to installing the S468 inplace of the S366?

Also, approximately what rpm did the turbo spool at before and after the QSF?
 
GOT-Torque said:
Nick, why did the installation of this QSF result in the movement of your downpipe backwards 1"? Wouldn't it just result in moving the turbo towards the passenger side 3/4"?

Or was this change due to installing the S468 inplace of the S366?

Also, approximately what rpm did the turbo spool at before and after the QSF?
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Yes, it moved the turbo a little less then 3/4" (a little less because the 3/4" dimension is at the angle of the t4 flange of the pdi manifold) to the passenger side. Thing is I could have used this spacer before because I had to beat up the down pipe to get it to fit between the trans and frame before the qsf. But, with the qsf just having beat in the down pipe wouldn't allow clearence with the turbo moved as stated above.

So I guess it was the down pipe placement difference between the s468 and the t66. I did have to weld a s400 flange on a silverline hx40 down pipe so it's possible the slight mis match in the flange orientation to the down pipe may have amplified my clearence/moving issues.

The turbo was around 2100 rpms before the qsf. Now it's more like 1900 or maybe a bit earlier. I am going to try to hit the races this saturday at MIR and will hopefully have my girl friend filming. The difference in spool time at launch is about 1/3rd of that without the qsf!!! My converter is a 15 blade left cut from Goerend for what it's worth as well.
 
Do you have a drive pressure gauge? I'm curious as to the affect on drive pressure at low boost conditions (when it is fully shut) and at WOT conditions (when it is fully open).
 
GOT-Torque said:
Do you have a drive pressure gauge? I'm curious as to the affect on drive pressure at low boost conditions (when it is fully shut) and at WOT conditions (when it is fully open).
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Yep, and I have some free time tonight I was planning to use to finally get some drive readings with this thing! Peak boost is higher (pegs 60psi gauge now, used to be just under 60 psi without qsf) so I suspect drive has gone up a bit unless getting the turbo lit faster generates more peak boost. We'll find out soon. This qsf has really done wonders to clean this truck up though (close to smoke free if you drive it without mashing the throttle down at 1400rpm with the converter locked etc.):ft:
 
NickTF said:
The s468 turbo itself resulted in roughly 9 tenths quicker ets, maybe 1 tenth of that drop being weather difference if that. Saying that the truck feels faster then it did with just the s468 swap but that's likely because of the thicker midrange the truck now has.
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Im sorry Nick. I wasn't clear on what I meant by "quick". I meant does the s468 with the QSF installed spool quicker than the T66 did? I'm extremely interested in this thing.
 
Well drive pressure suspiscions were spot on ha. I'm having problems with the actuator of the qsf it seems opening at all. I need to spend some time working those issues out. Drive without the gate opening was 105psi!!! I've since switched the regulator elbow over to regulating air to the bottom of the gate and am still adjusting as we speak to atleast get the drive down as it sits. I may have an issue with the air going to the actuator regarding a good hose seal. The fitting for the actuator is a very odd 10/32 to 1/8" hose barb which is damn near impossible to find! I've also removed the return spring all together. I'll keep the updates coming.
 
NickTF said:
Drive without the gate opening was 105psi!!!
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Under what throttle conditions, I assume WOT. Woundn't be surprised since it was trying to force all the air thru one side.

What was the drive with it all the way closed at no boost to 10 psi?

Thanks
 
GOT-Torque said:
Under what throttle conditions, I assume WOT. Woundn't be surprised since it was trying to force all the air thru one side.

What was the drive with it all the way closed at no boost to 10 psi?

Thanks
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Partial throttle at 10 psi was about 13psi. Yes, wot boost. If part throttle drive is 100+ psi you better go to church and pray lol:hehe:
 
I am going to discuss these issues with performance metal works. So far they have been top notch are working with me to solve my issues. Hey, with a new product they are to be expected and like I said, I want to go over some thing i've done myself.
 
NickTF said:
Well drive pressure suspiscions were spot on ha. I'm having problems with the actuator of the qsf it seems opening at all. I need to spend some time working those issues out. Drive without the gate opening was 105psi!!! I've since switched the regulator elbow over to regulating air to the bottom of the gate and am still adjusting as we speak to atleast get the drive down as it sits. I may have an issue with the air going to the actuator regarding a good hose seal. The fitting for the actuator is a very odd 10/32 to 1/8" hose barb which is damn near impossible to find! I've also removed the return spring all together. I'll keep the updates coming.
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No wonder the headgasket was trying to say F-you.
 
GRotman said:
No wonder the headgasket was trying to say F-you.
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Now way, it's a happy gasket:p. I've been checking the truck religiously and driving the pee out of it. Everything is fine so far thinking and hoping the coolant issue which showed up was something to do with the heat and the hotter temps out now. Ask anyone who knows me, I stay paranoid about this truck. Still doesn't make sense to me that something this heavy can go like it does hence the paranoid state ha:hehe:
 
http://www.turbodriven.com/images/turbofacts/img_turbine_32.jpg

If you look at this picture to me it doesn't seem that closing off either side vs. the other of the turbine housing will result in a mechanical advantage. It looks like both volutes of a dual volute turbine housing hit the turbine wheel at about the same spot, right at the meat of the turbine wheel's major diameter.

What would seem to be a slight difference though is keeping heat away from the cold side of the charger by closing off the volute closest to the cold side of the turbo. What do you guys think?

I had it run with the volute closest to the downpipe closed off. Think i'm going to try it with the volute closest to the cold side of the charger closed off.
 
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