GTX and EFR Turbo Porn

[URquattroGus]

http://wrxatlanta.com/forums/showthread.php?t=29939

The Borg Warner looks massive! Packageing nightmare maybe....

[Ross]

That's a really interesting read actually. I thought the 3076 vs 7670 was an odd comparison... when they compared the 3582 at the end that was very evenly matched, but with a slightly earlier spool.

The part most interesting to me was the description on the road, where it's making 5psi vs 2psi at lower RPMs. That's the extended tip that BW use showing it's value... that's what I was saying in your other thread... the lag suddenly becomes less of an issue when the car feels nice to drive round town, which I achieved with Hoffer76's latest K26/7 design and headwork. For example slowing to 50-60 on a motoway and then accelerating back up to 80-90 staying in 6th would be impossible before I had the work done, now it'll just about keep up with a 535d in that scenario and kill it above that :mischeif:

The EFR is so long though, I must admit the idea of getting that fitted would really put me off using one on an I5.

[JP]

Started of really good and then degraded into complete off topic rubbish about someones issues with their scooby. Wise up it's a scooby of course it's going to have issues.

[Jamo]

Read that report early last year the only thing to take for it is this

My conclusions are this. The dyno conclusions do not match what I "feel" on the road. On the road, I feel like this is much more lively than the GT or GTX3076R. Its interesting as in some road tests the EFR7670 shows the same spool up RPM as the GTX3076 w.82ar, but it feels so much snappier between shifts light load low RPM shifts. Meaning the normal day to day 2000-4000RPM shifting is about 50% better than it was before. In some logs I notice that the GTX would show say 2-3psi of boost at these really low RPM's, where the EFR is showing about 5psi. Its only a couple PSI but that makes huge difference in how it feels. You can see this on the dyno graphs where the EFR is making more TQ at 2000-2500.

This is the advantage of the efr and comp turbos triple bearings and where they outperfom other makes

[Billman]

I think it has more to do with the EFR's better wheel design than the odd Garrett with the single fins.

[Jamo]

Nope, but then i'm not debating I bought the turbo instead

[Billman]

I think the Comp turbos have better design also than the garrett GTX.

[prj]

Reduction of weight is key. If the turbine wheel weighs 2x less than other offerings and thus the entire shaft assembly weighs less while using an efficient bearing system then obviously accelerating it will be a lot easier.

[diesel des]

But the problem with efr is that the turbine isn't much lighter than the garrett. The efr has much thicker blades and also requires a larger diameter wheel to flow as much as the garrett due to the large volume the wheel itself takes up instead of exhaust gas. So the advantage isn't as much as I had first imagined.

[quattro84]

Haven't found any info on racing applications of these models at all. That means developing/improving is going to take long(er). Customer demands for these aftermarket applications is completely different compared to OEM supply.

Based on development budgets & knowledge Borg Warner /3k could make this an awesome product.
For now it's a bunch of funky marketing features with great potencial, but performance-wise not bringing it yet. http://www.perrinperformance.com/sha...otechbrief.pdf
Quality of machining wise it is best in class (like the OEM parts), can't see costs saving on series tooling.
But the overall external dimensions as such make it 'American car bonnet size market' exclusive for now.

[Jamo]

They have manufacturing issues with the efr turbo at present there was a hotside issue and reports of broken shafts
Once they come out with a second revision and not force buyers to use internal wastegate on the smaller ar housings they could be a big seller