Jump to content
SAU Community

Recommended Posts

So without dwelling on it too much more what turbochargers were you using and what was overall opinion on the twin configuration? It was a very packed engine bay with it all in there.

Having been through the twins already, retropectively would you have gone a single EFR or would you in future?

I was using -10's, -5's before that.

Packed, hot and hard to work on, especially when you have to replace them.

A few years back I did a comparison between a T04Z and twin -5's and the twins won hands down on response, from that day on I've been a twin guy.

However having said that, these new twin scroll efr's offer a much better result as a single, where response is no longer an issue with a bigger single. I'd love to whack an 8374 on my motor now to do the comparison again as I think it'd probably be close enough in response to now choose a single over twins.

Given what I went through, if I was to do it again I'd probably go a single 8374, just for the cost saving in fabrication and ease of maintenance.

Why arent you using them John? Still have that 6258 lying about too?

They turned out to be too big for my application. Full boost by about 5700rpm is too late for a circuit car.

They need more cubes to work at their best.

No, moved that on long ago, hopefully to a happy home.

Which I should probably check on to see if all went ok with install etc.

Interesting they were too big. Full race seemed to be poor pushing it to me for the 2L for 400whp.

If you compare the -10s to a 2871 from RB to SR i guess this would mean they aren't all that optimal.

Probably a 6758 would be better.

A few years back I did a comparison between a T04Z and twin -5's and the twins won hands down on response, from that day on I've been a twin guy.

To be fair, comparing a T04Z and twin -5s isn't fair if you're going to draw a conclusion on twins versus single. The -5s are full GT series turbos running the famed NS111 turbines. In contrast the T04Z is right from the start rated to a reasonable amount higher power level than the -5s - go for a pair of twins rated to more power than -5s and you should expect more lag so I'd say the same should apply to comparing a twin setup to a single rated to more power. The T04Z is also basically just an old T-series Garrett turbo that has been gifted with a ball bearing core, the wheel design is hardly cream of the crop.

I had in my head you had something of a nightmare with EFR turbos in the past, is this past history?

To be fair, comparing a T04Z and twin -5s isn't fair if you're going to draw a conclusion on twins versus single. The -5s are full GT series turbos running the famed NS111 turbines. In contrast the T04Z is right from the start rated to a reasonable amount higher power level than the -5s - go for a pair of twins rated to more power than -5s and you should expect more lag so I'd say the same should apply to comparing a twin setup to a single rated to more power. The T04Z is also basically just an old T-series Garrett turbo that has been gifted with a ball bearing core, the wheel design is hardly cream of the crop.

I had in my head you had something of a nightmare with EFR turbos in the past, is this past history?

True, however I've had both -5's and -10's, and when the comparison was done some 5-6 years ago the T04z was the single of choice in my neck of the woods. Obviously there's a lot more choice now, however back then not so.

EFR nightmare - yes, over or not? I'm not so sure. I haven't turned the key since November as I had an unexpected new addition to the family that's put a temporary hold on my car stuff. To be honest he came at a good time as I was getting ready to walk away from my car given the grief it's given me over the last few years. It will be back up and running in a couple of months for WTAC so I'm sure I'll have more to report then.

Fingers crossed you have a turnaround in luck when you get back into it, there are all sorts of other turbo options out there these days which are matching or bettering the EFRs in dyno comparisons - though there is a lot of hype out there about their response being better than what you can tell on dyno results, will be interesting to hear objective views on it as at the moment they definitely aren't at the top of my list of turbos I'd take a punt on - despite being one of the most interesting, just because of how big the doubt has got.

  • 3 weeks later...

Fingers crossed you have a turnaround in luck when you get back into it, there are all sorts of other turbo options out there these days which are matching or bettering the EFRs in dyno comparisons - though there is a lot of hype out there about their response being better than what you can tell on dyno results, will be interesting to hear objective views on it as at the moment they definitely aren't at the top of my list of turbos I'd take a punt on - despite being one of the most interesting, just because of how big the doubt has got.

What Turbo's do you like over BW EFR Lithium? FP, Comp Turbo?

Matt

Yep, bearing in mind I have never experienced the EFR turbos myself... like most, but the ball bearing HTA turbos so far have impressed the hell out of me. I know of no one under whelmed by results when they have tried one, too.

Hi guys,

Hoping I can get some advice or be pointed in the right direction.

I have a EFR 6758, PN-179388, SN-APA347100009. I'd like to confirm if I have a unit that I'm going to have issues with?

Thanks in advance.

You won't know until you try unfortunately.....

For what its worth I've never heard of anyone having a failure with that one... though given how thin on the ground the results are, and BW or suppliers obviously never advertise "You could have problems with this" its hard to say.

Ideally, you shouldn't.

Thanks for the replies.

What are the main causes of failures that are occurring?

Are they mainly with high boost setups?

No, I had one let go at around 14psi after 5mins on a dyno.

It's a casting issue, it'll just happen no matter what,...........if it's going to.

You may be worrying for nothing at this point.

Guest
This topic is now closed to further replies.



  • Similar Content

  • Latest Posts

    • That is surely the biggest gathering of Stageas in North America, ever!
    • Remember kids - if you can't afford to buy 2 GTRs......
    • I know people cry at the price of the Getrag 12-14k for a conversion now, but it really is a nice mid point. Not going to get change from 10k on a gearset installed.  $30k++ for sequential.   I know you run the risk of a damaged used one and parts are hard to get but as a street car gearbox its really hard to beat. If you enjoy a more traditional manual, its the choice no question.     
    • Time to decide what’s more import, your power level or your budget because you’re going to struggle to keep both 
    • Our Southern Highlands Cruise is proudly registered with “R U OK?” Day.  Sometimes the best way to check in on your mates is by getting out for a drive together. Sharing a common passion like cars creates the perfect space to chat, connect, and support each other.  A simple “R U OK?” can make all the difference. Let's enjoy the drive, the company, and look out for one another. PLEASE WEAR YELLOW FOR “R U OK?” DAY Sunday 14th September 2025 9:30AM Meeting Crossroads Homemaker Centre 10:00AM Cruise Departure Via Old Hume Hwy 11:45AM Arrival at Mittagong RSL Club Meet Location: Crossroads Homemaker Centre Final Destination: Mittagong RSL Club *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
×
×
  • Create New...