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Hi Geoff

Just to clarify would a EFR9174 "super core" , would fit my 8374EFR? Or does the housing needs to be modified?

Its on a street/weekend 2.7L 33 GTR with all supporting mods, I've got the feeling with 8374 EFR (400-450 awkw) I could go bigger later ,so might as well do it now .

Thanks

Bruce

 

15 hours ago, Shyboy said:

Hi Geoff

Just to clarify would a EFR9174 "super core" , would fit my 8374EFR? Or does the housing needs to be modified?

Its on a street/weekend 2.7L 33 GTR with all supporting mods, I've got the feeling with 8374 EFR (400-450 awkw) I could go bigger later ,so might as well do it now .

 

Yes, 9174 supercore will be plug and play for 8374 EFR turbo.  you dont need to remove the turbine housing, just loosen the cam bolts and swap supercores.  let me know if you need one we have a few incoming

On 5/3/2017 at 6:20 PM, Nismo 3.2ish said:

I was wondering if the 8474 is still being tested or dropped completely ?

still being tested.  you will probably get some more hints at sema.  The other EFRs will not change or get discontinued, they all remain relevant and have their place

  • Like 1

I've finally got my twin 6758 kit in the mail at the tuner's this week, so the build begins. Pretty excited to see what it will do both on the dyno and on the street. Will post full results in a month or two once it's done.

  • Like 2
30 minutes ago, Robzilla32 said:

 


What application is it best suited to? Most people on this site seem to bag the twins and say big (usually EFR) single is the way to go.

 

I am still interested to see more as well, There has been a lot said about them and I can see the potential but there is so little real world info I am treating it as unchartered territory so stick to what I have more an idea about.

 

For what it's worth, the main issue I have with twins on GTRs is stock location packaging etc - any turbo is a single turbo for what it's worth.  

 

I would love to see turbine speed sensors on twins going into a common plenum.  @Full-Race Geoff, have you guys done any turbine speed logging with the twins kits?

Edited by Lithium

They overlap though, so even if there's 2x 6258's they're just walking into 8374/9180 territory.

Could only imagine twins if going for truly stupid power on a 3.4L or something like that?

11 hours ago, Robzilla32 said:

Most people on this site seem to bag the twins and say big (usually EFR) single is the way to go.

I dont know many people on this site who bag twin EFRs, but single EFR is most common and for good reason: excellent performance and simple to retrofit existing greddy or HKS installations.  Twin IWG works better than single IWG and twin 6258s have a noticeably better throttle-link-to-boost-response than the big 9180.  Its not for everyone, but we have some customers in russia, europe and japan who are now only purchasing our twin RB kits. twin EFR means no dumptube headaches and no backpressure issues choking on 0.92

11 hours ago, Lithium said:

@Full-Race Geoff, have you guys done any turbine speed logging with the twins kits?

we have logged on the 6258 2.8L car here but it runs well and reliably, doesnt require much oversight.  the twins are almost never operating near max speed limits or emap choke points like the big singles so its not been nearly as critical as with the 9180 or 9174/8374. 

8 hours ago, Kinkstaah said:

They overlap though, so even if there's 2x 6258's they're just walking into 8374/9180 territory.

Could only imagine twins if going for truly stupid power on a 3.4L or something like that?

in terms of mass airflow rate, twin 6258s are a little bigger than a single 8374.  but smaller than 9174 or 9180. 

Edited by Full-Race Geoff
I dont know many people on this site who bag twin EFRs 


Sorry my post wasn't worded very well. I meant to refer to twins in general being considered inferior to a modern big single. I was wondering if there was something different about the EFR solution that changed that thinking?

Cheers
4 hours ago, Full-Race Geoff said:

we have logged on the 6258 2.8L car here 

Do you have any data on it?  I often wonder if the front and rear ones work similarly hard or if there are situations one may end up taking more load than the other.  I'd guess that more likely with stock location twins, but still curious

  • Like 1
4 hours ago, Lithium said:

Do you have any data on it?  I often wonder if the front and rear ones work similarly hard or if there are situations one may end up taking more load than the other.  I'd guess that more likely with stock location twins, but still curious

Thats something im actually curious about. 

Speed sensors on both turbos to see just how they both share the work load together. 

Curious if its the rear turbo that works harder like the factory stuff does?

Obviously the removal of that horrible "twin turbo pipe" would help eliminate most of that. 

On 08/05/2017 at 6:38 AM, Robzilla32 said:

 


Sorry my post wasn't worded very well. I meant to refer to twins in general being considered inferior to a modern big single. I was wondering if there was something different about the EFR solution that changed that thinking?

Cheers

The 'twins' comparison you see around here is alawys done in the context of rb26 stock location/piping GT28 twins, vs singles. That somewhat skews things.
Doing a full custom twins vs full custom single with no constraints (read AC/PS pump in the way) and using EFRs for both you'd probably find the comparison quite different to an 8374 vs -5's for example

  • Like 6
2 hours ago, bri73y said:

My twin 6258s made over 700hp at all four last tune. All in (28psi) at around 4700rpm. Not too shabby.

Sounds mad :)

Please post the graph and any other info, love to see it

6 hours ago, bri73y said:

My twin 6258s made over 700hp at all four last tune. All in (28psi) at around 4700rpm. Not too shabby.

Which GTR was this in? I am working on doing the twin setup on mine as well but am having issues with the power steering pump. Did you have an R32? Did you replace your p/s pump with something else?

11 hours ago, bri73y said:

My twin 6258s made over 700hp at all four last tune. All in (28psi) at around 4700rpm. Not too shabby.

Nice!  Is the R33 still cranking with the 7670?

Out of interest the single EFR9180 on my mate's RB28DET is all in at about the same boost at similar rpm.

 

Edited by Lithium
6 hours ago, minesskyline said:

Which GTR was this in? I am working on doing the twin setup on mine as well but am having issues with the power steering pump. Did you have an R32? Did you replace your p/s pump with something else?

You need to use an R33 or R34 power steering pump, then everything will fit.

  • Like 1
1 hour ago, Lithium said:

Nice!  Is the R33 still cranking with the 7670?

Out of interest the single EFR9180 on my mate's RB28DET is all in at about the same boost at similar rpm.

 

Sure is, can't see that changing anytime soon, it's a great combo for anything you want to do. It's currently having a makeover with a wide body kit and respray in Audi Nardo Grey. It's nearly complete, looks good, but most importantly I will now be able to run my GTR wheels/tyres (wider) under her.

Yes, Brett (from Full Race) has told me several times there's no real advantage in going 9180 over my twins.I did try the larger rears (0.8) on the twins last year chasing more power but gained bugger all whilst losing easily 400-500rpm in response. 

 

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