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Hi guys I was wondering what your fuel economy is like now compared to before and compared to a normal factory Turbo? I am leaning towards a full engine swap but I like the idea of having the benefits of an NA for good throttle response.

Hi guys I was wondering what your fuel economy is like now compared to before and compared to a normal factory Turbo? I am leaning towards a full engine swap but I like the idea of having the benefits of an NA for good throttle response.

As he has said is fine provided you have the gtst injectors and afm. as for adding in a few psi and not getting as much as a Gtst - well I got more - as long as you have a good free flowing exhaust why don't you think you'd get as much as a gtst?

My bad, I meant that 10 psi on a DE+T with a stock ecu compared to a stock DET. As in ping and engine death etc. The gains, if tuned correctly are more with the same air/fuel/timing as the engine can do more with it due to compression.

Hi guys I was wondering what your fuel economy is like now compared to before and compared to a normal factory Turbo? I am leaning towards a full engine swap but I like the idea of having the benefits of an NA for good throttle response.

Hey mate.

My fuel economy hasn't really changed, if you drive the car the same way as you did when it was NA the fuel economy will be the same. If you boost the tits off the car everytime you drive, then fuel economy will follow suit.

On the highway, even on a stock ecu, boost and injectors, running 10psi too much fuel pressure due to a dud fuel reg (soon to be replaced) I can get 10L/100km or lower even with people in the car and aircon on.

My bad, I meant that 10 psi on a DE+T with a stock ecu compared to a stock DET. As in ping and engine death etc. The gains, if tuned correctly are more with the same air/fuel/timing as the engine can do more with it due to compression.

Ahh right, I get you now. But really, to the guy asking the question - if you want to get anything out of your turbo gear, get a tuneable ecu and u'll notice a big difference

Also, When I first turboed the car running all standard turbo gear, my economy actually improved because the turbo was helping the motor do the work - provided you are not just thrashing, it will be fine.

Done this turbo conversion last weekend with my rb20de.

Thought i should take some pics of the plugs on the side of the block for people as i dont think i have seen any on here yet.

for the oil return i used proflow part no. PFE841-12 3/4 NPT to Barb.

Also fuel economy is pretty much the same too.

post-89837-0-73325300-1330698637_thumb.jpg

  • 2 months later...

Hi Guy's,

As mentioned I did DE+T conversion on my R32 gts25 last year using rb20det parts and have been happy with the results.

However I think I have a problem with the factory bov. With the bov plumbed in correctly to the inlet manifold the car is sluggish (basically feels like a na, with a little more power).

As a test I plumbed the bov into a smaller (ie thinner) vacum port and the car drives like a completely different car. Boost is strong and the car pulls hard through all the gears. There is the sound of compressor surge sometimes as I close the throttle. I expected this though and confirms the bov is not working as it does not have a proper source of vacum. Sure enough when I revert back to the correct setup (plumbed with the correct hose direct into inlet manifold) the car is sluggish again. The bov must be opening on throttle. Also to add I don't have a boost gauge as yet so not sure what's happening boost wise.

So the question I have is - should the factory bov be able to handle the increased flow of the na engine plus the turbo (I am using a standard rb20 turbo) or can it only handle the factory turbo setup? Would I best fitting an aftermarket plumback bov (like a turbosmart kompact)?

I have also removed the bov and inspected and it seems fine (though there is not much to check)

Cheers

Jason

Edited by gts25

Hi Guy's,

As mentioned I did DE+T conversion on my R32 gts25 last year using rb20det parts and have been happy with the results.

However I think I have a problem with the factory bov. With the bov plumbed in correctly to the inlet manifold the car is sluggish (basically feels like a na, with a little more power).

As a test I plumbed the bov into a smaller (ie thinner) vacum port and the car drives like a completely different car. Boost is strong and the car pulls hard through all the gears. There is the sound of compressor surge sometimes as I close the throttle. I expected this though and confirms the bov is not working as it does not have a proper source of vacum. Sure enough when I revert back to the correct setup (plumbed with the correct hose direct into inlet manifold) the car is sluggish again. The bov must be opening on throttle. Also to add I don't have a boost gauge as yet so not sure what's happening boost wise.

So the question I have is - should the factory bov be able to handle the increased flow of the na engine plus the turbo (I am using a standard rb20 turbo) or can it only handle the factory turbo setup? Would I best fitting an aftermarket plumback bov (like a turbosmart kompact)?

I have also removed the bov and inspected and it seems fine (though there is not much to check)

Cheers

Jason

I've seen the stock bov being used on setups making well over 300rwkw. Where have you plumbed it into? Have you got another one you could try? I think yours is possibly a bit worn out, sounds like it doesn't have enough spring pressure to keep it shut.

Hey Martin,

I have it plumbed in as it should be - from the bov air nipple into the metal air that's bolted under the intake pipe (to throttle body) and from the other end of this pipe into the top of the inlet manifold towards the back (where the charcoal canister line used to plumb into on the NA setup). Does this make sense?

I don't have a spare bov to try but am trying to get hold of a gtr one

Jason

Hey Martin,

I have it plumbed in as it should be - from the bov air nipple into the metal air that's bolted under the intake pipe (to throttle body) and from the other end of this pipe into the top of the inlet manifold towards the back (where the charcoal canister line used to plumb into on the NA setup). Does this make sense?

I don't have a spare bov to try but am trying to get hold of a gtr one

Jason

Yes makes sense, should work like that. I think try to get hold of another bov, GTR one will be even better. How hard is it to push the valve open by hand, do you know? I've got a stock R34 bov sitting here that is quite hard to push open, it's fairly stiff.

Hey Martin,

I have it plumbed in as it should be - from the bov air nipple into the metal air that's bolted under the intake pipe (to throttle body) and from the other end of this pipe into the top of the inlet manifold towards the back (where the charcoal canister line used to plumb into on the NA setup). Does this make sense?

I don't have a spare bov to try but am trying to get hold of a gtr one

Jason

Are you sure the vacuum line from the bov is going to the intake manifold BEHIND the throttle? This vacuum is used to equalise the pressure in the BOV so it doesn't creep open under boost (as regardless how much boost you are running at WOT there will be the same pressure in-front and behind the BOV). It then pulls open quickly when the throttle closes (as not only does it have boost pushing it open, it has vacuum on the other side from the intake manifold pulling it open at the same time). If it isn't connected (or in the right place) without equalising the pressure I can see that the boost could push past it.

Are you sure the vacuum line from the bov is going to the intake manifold BEHIND the throttle? This vacuum is used to equalise the pressure in the BOV so it doesn't creep open under boost (as regardless how much boost you are running at WOT there will be the same pressure in-front and behind the BOV). It then pulls open quickly when the throttle closes (as not only does it have boost pushing it open, it has vacuum on the other side from the intake manifold pulling it open at the same time). If it isn't connected (or in the right place) without equalising the pressure I can see that the boost could push past it.

the bov is plumbed after the throttle into the top of the inlet manifold, towards the rear. is this not the correct location? the na manifold has only 1 vacum port in this location for the charcoal canister and the gtst manifold has an additional one for the bov

Yes makes sense, should work like that. I think try to get hold of another bov, GTR one will be even better. How hard is it to push the valve open by hand, do you know? I've got a stock R34 bov sitting here that is quite hard to push open, it's fairly stiff.

hey martin,

i checked the valve, i can push it with my thumb but its quite stiff....

jason

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