SugarMouth
Drag Race Newbie
- Location
- Nevada
Finally some info on the turbo inlets.
https://www.facebook.com/VolkswagenRacingUK/posts/1188806521227255
https://www.facebook.com/VolkswagenRacingUK/posts/1188806521227255
7
Flow info on Turbo elbows
- Thread starter SugarMouth
- Start date
Diggs24
Autocross Champion
- Location
- de plains! de plains!
- Car(s)
- 2015 GTI
I guess the question now is, do the IS20 or IS38 need more air than the stock unit provides?
"We’ve seen some surprisingly significant power and torque increases from the fitment of the VWR High-Flow Turbo 90 as a result of the faster turbo spool and increased airflow it generates."
Why not provide them?
"We’ve seen some surprisingly significant power and torque increases from the fitment of the VWR High-Flow Turbo 90 as a result of the faster turbo spool and increased airflow it generates."
Why not provide them?
Noise
drrck
Go Kart Champion
- Location
- Zeeland, MI, USA
More like, does it even matter if the elbow can flow more if the turbo inlet can't handle the increased flow... I would imagine there are gains to be had at some point, but with an IS20 I'm guessing its quite small.
0bLiViOuS
Go Kart Champion
- Location
- Orange County
Multiple people reported butt dyno differences and others nothing. I think there is a gain, especially if that pressure difference is accurate. A stage 2 is flowing around 500CFM is what I'm guessing (1.6cfm/per hp) which means the stock unit is probably much more a restriction than your air filter. Probably also shows why there is not a lot of gain with just a filter replacement. I'd love to see a dyno of an intake and then swap this on and see if there are gains.
GLoBaLReBeL
Ready to race!
- Location
- South Bend, IN
Does George's intake have the same diameter tubing?
0bLiViOuS
Go Kart Champion
- Location
- Orange County
Ya the BMS intake is larger than the stock tubing I believe and George has said it'll only work with their TIP and not the stock one (which I think you could do if you bought a reducer, but why). When I installed my IE on the stock TIP, I remember the TIP being slightly smaller (slight taper to the silicone hose) but when I installed my CTS it was the same size as the CF intake part.
SugarMouth
Drag Race Newbie
- Location
- Nevada
So Raceline is saying they have seen 5hp-15hp. Stage 2 cars see double digits.
0bLiViOuS
Go Kart Champion
- Location
- Orange County
Wow that's a really big claim..
0bLiViOuS
Go Kart Champion
- Location
- Orange County
Fwiw so users understand the graph better, at 350cfm (where the blue line stops) that's basically stock levels. So even at stock levels, it's a pressure restriction of .75psi. At a stage 2 level, it's about 1.25psi. The higher the restriction causes an overall higher pressure ratio on the turbo. If we had a compressor map this would actually help, but at least on the IS20 and IS38, lower is better 
JakeFromStateFarm
Ready to race!
- Location
- Denver, CO
Fwiw so users understand the graph better, at 350cfm (where the blue line stops) that's basically stock levels. So even at stock levels, it's a pressure restriction of .75psi. At a stage 2 level, it's about 1.25psi. The higher the restriction causes an overall higher pressure ratio on the turbo. If we had a compressor map this would actually help, but at least on the IS20 and IS38, lower is better
This sort of data is all new to me but let me know if I have this correctly. Let's say that at stage 2 where it's 1.25psi. Does that mean that at peak boost the turbo is "working" 1.25psi harder than if there was no restriction?
0bLiViOuS
Go Kart Champion
- Location
- Orange County
Sort of. It's more shifting the pressure ratio. The formula is:
CPR = (psig+ambient)/ambient
CPR = compressor pressure ratio
Psig = psi gauge (i.e. how much boost you're pushing)
Ambient = ambient (14.7psi at sea level)
What this does is subtract the pressure from the ambient. So for example I'll use 25psi boost on the stock TIP
CPR = (25+13.5)/(14.7-1.2) = 2.85CPR
Now with the VWR, that would be:
CPR = (25+14.5)/14.5 = 2.72CPR
If you just added 1.2psi to the boost so it's 26.2psi:
CPR = (26.2+14.5)/14.5 = 2.8CPR
So even adding the boost difference brings you to a lower PR so it would perform better. The reason I used 14.5 for the VWR TIP is because that still has some pressure drop. Hope that helps
CPR = (psig+ambient)/ambient
CPR = compressor pressure ratio
Psig = psi gauge (i.e. how much boost you're pushing)
Ambient = ambient (14.7psi at sea level)
What this does is subtract the pressure from the ambient. So for example I'll use 25psi boost on the stock TIP
CPR = (25+13.5)/(14.7-1.2) = 2.85CPR
Now with the VWR, that would be:
CPR = (25+14.5)/14.5 = 2.72CPR
If you just added 1.2psi to the boost so it's 26.2psi:
CPR = (26.2+14.5)/14.5 = 2.8CPR
So even adding the boost difference brings you to a lower PR so it would perform better. The reason I used 14.5 for the VWR TIP is because that still has some pressure drop. Hope that helps
JakeFromStateFarm
Ready to race!
- Location
- Denver, CO
Yeah that helps very much, thanks. Interesting! So higher pressure ratio means more work for the turbo, right? So it turns out that these inlets may be better for our turbos after all.