Author Topic: VF Turbo Info  (Read 10774 times)

November 25, 2014, 03:52:50 PM
Reply #60

h22sean

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Many people overlook this and end up with unexpected expenses. General rule is, calculate what all the mods are gonna cost, save up double that and have a credit card or personal loan on standby for all the unexpected stuff. You can ask any guy who has ever modded a car or two. That is how it works without fail.
Not sure if my mods were planned and researched properly or if I've just been lucky but that is not how it went with mine at all. Got the turbo and intercooler fitted, tuned by Chett and that was that. I'm sure it's a different story if you go BIG but then Chett and Wayne are always upfront about what's needed and what it'll end up costing.

It depends a lot on how well you research for sure. Depends how big you want to go too so you are right. It depends a lot on whether it is a turbocharged car from factory too.
2006 Forester XT Premium - Kinugawa TD05H-20G, STI Intercooler, Pyro OCC, Air Pump Delete, 3" downpipe and exhaust
2007 Honda Jazz DSI
1998 Honda Prelude VTI-R
1995 Honda Ballade 180E - VTEC Head, High CR Pistons etc. 118wkW
1994 Honda Balade 160i - Turbocharged

November 25, 2014, 04:10:32 PM
Reply #61

Stev0

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With my HKS EVCS boost controller I can boost 1.2bar pretty close to 3.3k. Its unbelievable how much more responsive the car is! I switch it off and drive on wastegate pressure, otherwise I drive like a box.
Nice!




I've also been told a proper 3" bell mouth down pipe makes a big difference in spooling?

Sav/traceman,

You can drive any turbocharged car at any rpm without boost. It's dependent purely on throttle position. The higher the rpm the less throttle you need to start generating boost but you can go through the entire rev range without boosting.

The stock downpipe has a flat flange with one hole in it for the exhaust gas to flow through. Problem is the opening at the discharge side of the exhaust housing is basically oval shaped. On the one side of the oval sits the exhaust wheel and on the other side the port for the wastegate. The stock flange basically only has a opening for the exhaust wheel so the wastegate gasses don't have a direct flow path. If you use the stock downpipe with a 76mm exhaust system you will probably struggle with boost spikes when going WOT(wide open throttle) and boost creep. With a bell mouth downpipe the pipe is shaped the same as the discharge of the exhaust housing and then goes to round in a smooth way allowig the wastegate gas to flow freely into the exhaust and this should help with boost creep and spike.

However, the more restrictive stock exhaust system actually assists with boost control in a way because there is more back pressure so when you do fit a bellmouth downpipe and exhaust system you will probably still struggle with creep in the higher rpm ranges with the TD04 although this is a minor issue because the stock turbo runs out of breath before that really happens. Will only be apparent with long 5th gear pulls. Boost spikes can be solved by fitting a 3-port EBCS instead of the bleed off 2-port stock one. You can control the spikes with the stock EBCS but this will make the turbo spool up later as you need to control the boost progressively to stop it from spiking.

Anyway, the point is basically that if you do any mods to the exhaust system or intake system you need to remap for sure. Remember, the turbo forms part of the exhaust system. Each turbo flows air differently and the map needs to be adapted for that. I f you decrease the restriction on the intake side this will also change how the turbo flows as it can now suck air more easily. So keep that in mind for any mods you do to the engine. Doing mods to the intake or exhaust and not having it mapped can have catastrophic consequences so just don't do it.

When you are planning to do a mod on the engine, always remember to also budget for the tuning. Many people overlook this and end up with unexpected expenses. General rule is, calculate what all the mods are gonna cost, save up double that and have a credit card or personal loan on standby for all the unexpected stuff. You can ask any guy who has ever modded a car or two. That is how it works without fail.

Strangely I hated the spooling of the 3076. To me it feels like it wants a LOT of boost to make power. It will totally suck on a gymkhana course where the 20g and VF's should hand it to it with its less lag.

Straight line though... It will be a different story.

Look, the 3076 is meant for bigger power numbers and if you look at the compressor map it needs probably 1.2bar or so for it to really get into it's optimum efficiency range so yes a smaller turbo would be better suited for track or gymkhana and that's why I opted for the 20G with the smaller exhaust housing.

Would I have to upgrade the stock STI injectors if I went that route?

Jeep Commander CRD - GDE Hot Tune
ex Prodrive Xt, X, XT, WRX STI, Outback 3.0R

November 26, 2014, 07:16:35 AM
Reply #62

h22sean

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Do you mean a 3076 setup? Yes, you can decap the stock injectors and have them flow tested to see that they all flow within 3% or so of each other. When our injectors are decapped, we get around 900cc or so and they work just fine. A lot of guys in states have done it. That would be good for running e50 or more depending on boost levels.

Other route is to buy bigger injectors but they are expensive. Will work out between R5k-6k for a set of 1000cc injectors.
2006 Forester XT Premium - Kinugawa TD05H-20G, STI Intercooler, Pyro OCC, Air Pump Delete, 3" downpipe and exhaust
2007 Honda Jazz DSI
1998 Honda Prelude VTI-R
1995 Honda Ballade 180E - VTEC Head, High CR Pistons etc. 118wkW
1994 Honda Balade 160i - Turbocharged

November 26, 2014, 07:56:56 AM
Reply #63

Stev0

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Sorry, I was referring to the 20G
Jeep Commander CRD - GDE Hot Tune
ex Prodrive Xt, X, XT, WRX STI, Outback 3.0R

November 26, 2014, 09:45:45 AM
Reply #64

sav

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It depends a lot on how well you research for sure. Depends how big you want to go too so you are right. It depends a lot on whether it is a turbocharged car from factory too.
Yep, the plan was never to go huge but rather have usable power & torque without compromising reliability.

My mods went in this order:
-Brakes
-Forged build
-Suspension
-TD04 Tune @ 1.0 bar
-Cooling
-VF48+STi tmic & tune @ 1.2 bar

I'm sure the engine could take a lot more but I'm more than happy with the results and suspect anything more would start compromising other things.
2007 XT Premium Sportshift (Decat, VF48 @ 1.2 bar, STi TMIC, Chett tjooned, BBK, coilovers, etc etc eish!)

May the Forester be with you...

November 26, 2014, 11:34:45 AM
Reply #65

h22sean

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Sorry, I was referring to the 20G

With the 20G the stock injectors are good for about 1.2bar max but you will be running close to the limit. I would much rather decap and then you are safe even if you go e50.
2006 Forester XT Premium - Kinugawa TD05H-20G, STI Intercooler, Pyro OCC, Air Pump Delete, 3" downpipe and exhaust
2007 Honda Jazz DSI
1998 Honda Prelude VTI-R
1995 Honda Ballade 180E - VTEC Head, High CR Pistons etc. 118wkW
1994 Honda Balade 160i - Turbocharged

November 27, 2014, 08:27:46 AM
Reply #66

Stev0

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It depends a lot on how well you research for sure. Depends how big you want to go too so you are right. It depends a lot on whether it is a turbocharged car from factory too.
Yep, the plan was never to go huge but rather have usable power & torque without compromising reliability.

My mods went in this order:
-Brakes
-Forged build
-Suspension
-TD04 Tune @ 1.0 bar
-Cooling
-VF48+STi tmic & tune @ 1.2 bar

I'm sure the engine could take a lot more but I'm more than happy with the results and suspect anything more would start compromising other things.

With the VF, you should see about 220/230 kw from the engine at that boost. Its going to be properly quick.
Jeep Commander CRD - GDE Hot Tune
ex Prodrive Xt, X, XT, WRX STI, Outback 3.0R

November 27, 2014, 09:09:33 AM
Reply #67

sav

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It depends a lot on how well you research for sure. Depends how big you want to go too so you are right. It depends a lot on whether it is a turbocharged car from factory too.
Yep, the plan was never to go huge but rather have usable power & torque without compromising reliability.

My mods went in this order:
-Brakes
-Forged build
-Suspension
-TD04 Tune @ 1.0 bar
-Cooling
-VF48+STi tmic & tune @ 1.2 bar

I'm sure the engine could take a lot more but I'm more than happy with the results and suspect anything more would start compromising other things.

With the VF, you should see about 220/230 kw from the engine at that boost. Its going to be properly quick.
Yep, she is moving. :)

STi with same turbo at 1.0 bar boost is 220kw at the fly so this should be closer to 240 I reckon? Either way, I'm extremely happy with it except for the fact that nobody wants to play. Been trying to find a Gti7 for weeks but they seem to be more into posing.
2007 XT Premium Sportshift (Decat, VF48 @ 1.2 bar, STi TMIC, Chett tjooned, BBK, coilovers, etc etc eish!)

May the Forester be with you...

November 27, 2014, 10:22:21 AM
Reply #68

Stev0

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You would still need a bunch of fuel and water injection to get the temps down to make that power reliably.


Dont waste your fuel with GTI7's. Rather look for RS3's :D :D 
Jeep Commander CRD - GDE Hot Tune
ex Prodrive Xt, X, XT, WRX STI, Outback 3.0R

November 27, 2014, 10:29:16 AM
Reply #69

sav

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You would still need a bunch of fuel and water injection to get the temps down to make that power reliably.


Dont waste your fuel with GTI7's. Rather look for RS3's :D :D
True, either way I've never been bothered with numbers, it's going awesomely which is the only important part.

LOL yeah I could stay with a GTI7 when I still had the old turbo @ 1.0 bar. Should be able to pass now. :D RS3 is blistering quick, I suspect it would end badly for me.
2007 XT Premium Sportshift (Decat, VF48 @ 1.2 bar, STi TMIC, Chett tjooned, BBK, coilovers, etc etc eish!)

May the Forester be with you...

November 27, 2014, 10:39:04 AM
Reply #70

Stev0

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Boost more  8) 8) 8)

1.4barrrrr mmmmmmmmm
Jeep Commander CRD - GDE Hot Tune
ex Prodrive Xt, X, XT, WRX STI, Outback 3.0R

November 27, 2014, 10:43:32 AM
Reply #71

Charlie

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The talk of all this power makes me drool & jealous.
2007 Forester 2.5 XT A/T
De Cat, WHP Serviced & Chett-Tuned (I now have 2 gas monsters)
2000 Pajero 3.5 V6 SWB (Gas Monster)

November 27, 2014, 10:50:40 AM
Reply #72

sav

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Boost more  8) 8) 8)

1.4barrrrr mmmmmmmmm

Chett did say he could go higher but then I'd need to run octane booster. No thanks.
2007 XT Premium Sportshift (Decat, VF48 @ 1.2 bar, STi TMIC, Chett tjooned, BBK, coilovers, etc etc eish!)

May the Forester be with you...

November 27, 2014, 10:58:29 AM
Reply #73

Stev0

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You would be amazed how much difference it really makes. The sti is slow and lethargic on pump fuel. Nf street is  50zar  per tank.  Try it.
Jeep Commander CRD - GDE Hot Tune
ex Prodrive Xt, X, XT, WRX STI, Outback 3.0R

November 27, 2014, 11:01:50 AM
Reply #74

sav

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You would be amazed how much difference it really makes. The sti is slow and lethargic on pump fuel. Nf street is  50zar  per tank.  Try it.
Yep, I've got NF Street which I'm keeping in case I can't get 95.

The car is tuned for 95 so I doubt it would make any difference unless it's retuned for 1.3/4?
2007 XT Premium Sportshift (Decat, VF48 @ 1.2 bar, STi TMIC, Chett tjooned, BBK, coilovers, etc etc eish!)

May the Forester be with you...