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Why are all VR38's with aftermarket turbos still twin turbo when everyone in the RB and 2JZ scene converts their cars to big single turbos? does the V6 configuration make twin turbos more effective when it comes to top end power vs responsiveness? I noticed that its not just drag guys keeping it twin turbo but also Chris Forsberg in his formula d VR38 powered 370Z and time attack cars.

It's a practicality thing. With an I6 it's not that hard to have a single turbo, it actually reduces the amount of intake piping you have. With a V6 unless you want to do a hot V setup and completely re-engineer the engine + transmission a single turbo would have a ridiculous amount of exhaust piping to get to the turbine, like so:

image.png.16a119170d7d3d84750767b228a85bcb.png

Or you can have two parallel turbos and it looks like this:

image.thumb.png.09062ddfeedc31324ac95837196ad64c.png

  • Like 4

Put it this way, putting twin turbos on an inline 6 is stupid and putting a single turbo on a V6 is stupid.

Also comes down to practicality.

To make twins work on an inline properly you would want twin plenums, twin ICs, twin throttles so there are issues with shuffling, flow disturbances, etc. No-one has ever really attempted that hence all twin setups on RBs and 1/2JZ all suck balls. Its like trying to put two cocks in one bum.

  • Like 2
  • Haha 6

Question 

 

Why is it then that some aftermarket turbo kits for the LS have the turbo only being feed by the one bank?

Yes, the good ones have the both banks merge, but I have seen some big Hp cars running only of 1 bank.

Meh 

20 minutes ago, mlr said:

Question 

 

Why is it then that some aftermarket turbo kits for the LS have the turbo only being feed by the one bank?

Yes, the good ones have the both banks merge, but I have seen some big Hp cars running only of 1 bank.

Meh 

You sure about that? typically only one new manifold is required and the standard driver side manifold is reused. So when looking at a kit you may be misled thi king only one bank feeds it, but that would suck balls and I have never seen an ls kit like that.

the cross over pipe typically runs ender engine between belhousing and block then up to join passenger side bank.

  • Thanks 1
3 hours ago, Ben C34 said:

You sure about that? typically only one new manifold is required and the standard driver side manifold is reused. So when looking at a kit you may be misled thi king only one bank feeds it, but that would suck balls and I have never seen an ls kit like that.

the cross over pipe typically runs ender engine between belhousing and block then up to join passenger side bank.

 

36 minutes ago, GTSBoy said:

Running a V engine with only 1 bank powering the turbine would be daft. Massively different tunes required for each bank, to account for the massive backpressure on the one with turbine.

Did more googling

The Saab 9-5 3.0t did

It made about 200hp with 3.5 lb.

Even die hard Saab fanboys hated the engine

Sounds like a SR20 designed by NASA

So there you go, you can, and they did, but they shouldn't have, because it is shit.

1021022469_images(5).jpeg.627f812858d9db4c91f84ceb03e8a2a2.jpeg

  • Like 1
  • Confused 2
On 01/08/2020 at 9:59 PM, WR33KD said:

Once he is done braking records it will be put back to gt3 class and be used as a circuit car. 

What records is it going to break?   Aside from creating "new" records I am pretty sure it can only really shoot for "pro mod" type times, or possibly an outright AWD record.  I doubt very much any of the GTR record lists/holders will consider it a valid entry.  

In regards to the main question, I think the main points are covered - twins are more practical and logical on a V6 and a single is more logical on a straight 6.   I got the impression the STHitec 4WD funny car went single partly as a point of difference as opposed to specifically for performance reasons.

Yeah ST Hitec in NZ have a Vr38 that is above.

It has now removed the Garrett turbo and will be running a single Giant precision turbo.

Only been out for shake downs but is already Australasia's fastest R35 running 7's at 180mph+.

 

Edited by Stixbnr32
Just now, Stixbnr32 said:

Yeah ST Hitec in NZ have a Vr38 that is above.

It has now removed the Garrett turbo and will be running a single Giant precision turbo.

Only been out for shake downs but is already Australasia's fastest R35 running low 7's at 180mph+.

 

Pretty sure it ran 7.6, and while I love the car and it should go VERY fast, but it's not an R35 - it should not be compared with the likes of SIN35 which is actually an R35 GTR... not a tube frame chassis.   

Will be interesting to see how it goes, though - but apples vs oranges.

  • Like 1
5 hours ago, WR33KD said:

Doesn’t really matter the American scene will just make a new category as it’s seems that the 35 chassis has 15 different groups that you can run in to hold a record.

 

as does every other GT-R created by the Aussie scene

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