[Closed] Borg Warner Efr Series Turbos

[scandyflick]

My 6258 got pulled off the other day. Still in excellent condition after its first 17psi track outing.

Should have everything back together soon, then back on the dyno without an air leak... Hopefully.

[scandyflick]

Still looking good.

Turbine housing and exhaust manifold have both been ceramic coated, flange surfaces on the inlet manifold have been machined (3 of 4 were out of tolerance apparently), oil drain will be rectified next time I have a day off. Then I'll slap it back together, and it get back on the dyno, hopefully, with the mystery air leak sorted out.

[bradsm87]

Tha coating looks great. I'll do that on mine for sure.

I'm just REALLY frustrated about which one to get. "over-revving" these turbos seems to be a big no-no which sux because a 6258 looks ideal for awesome response on a 2.15L SR20 but even though I'm happy to run it down to 60% efficiency up near rev limiter, it's going beyond the "recommended" RPM. Not interested in th 6758 at all. It's compressor map looks horrible and the 7064's inducer is smaller anyway.

I just wish turbos were more customisable. I think the 70mm compressor model should also be offered with a 61mm turbine for smaller engines and a T3 divided .82 housing as well to fill the gap between the T25 .64 and the T4 divided .92/T3 .82 (both spool about the same).

[Sayers]

Tha coating looks great. I'll do that on mine for sure.

I'm just REALLY frustrated about which one to get. "over-revving" these turbos seems to be a big no-no which sux because a 6258 looks ideal for awesome response on a 2.15L SR20 but even though I'm happy to run it down to 60% efficiency up near rev limiter, it's going beyond the "recommended" RPM. Not interested in th 6758 at all. It's compressor map looks horrible and the 7064's inducer is smaller anyway.

I just wish turbos were more customisable. I think the 70mm compressor model should also be offered with a 61mm turbine for smaller engines and a T3 divided .82 housing as well to fill the gap between the T25 .64 and the T4 divided .92/T3 .82 (both spool about the same).

What are the RPM limits on the EFR's?

[Sayers]

Still looking good.

Turbine housing and exhaust manifold have both been ceramic coated, flange surfaces on the inlet manifold have been machined (3 of 4 were out of tolerance apparently), oil drain will be rectified next time I have a day off. Then I'll slap it back together, and it get back on the dyno, hopefully, with the mystery air leak sorted out.

That looks real clean. Who did the coating and what did it cost for the housing?

[bradsm87]

What are the RPM limits on the EFR's?

Different for each one. It's the far right line on the compressor map. 167,000rpm for the EFR 6258.

[scandyflick]

That looks real clean. Who did the coating and what did it cost for the housing?

AAA Exhausts in Richmond (SA), cost $80.

[badhairdave]

I just wish turbos were more customisable. I think the 70mm compressor model should also be offered with a 61mm turbine for smaller engines and a T3 divided .82 housing as well to fill the gap between the T25 .64 and the T4 divided .92/T3 .82 (both spool about the same).

So get a 3071?

Anyway, i was at a track day recently and another s13 was out there with a .64 6758.

Basic built red top, 260/12mm camtechs, greddy intake manifold maybe and a high mount manifold. The thing was making a touch over 300rwkw at 21psi all in by 3500. Cheating with E85 but still very impressive.

I certainly wouldn't discount them.

[bradsm87]

So get a 3071?

Anyway, i was at a track day recently and another s13 was out there with a .64 6758.

Basic built red top, 260/12mm camtechs, greddy intake manifold maybe and a high mount manifold. The thing was making a touch over 300rwkw at 21psi all in by 3500. Cheating with E85 but still very impressive.

I certainly wouldn't discount them.

3071R is bigger that a 7064. I want smaller. I'd use a 7064 over a 6758, even if I lost 150rpm of spool (which is all the dirrefence would be) in exchange for 10psi less exhaust manifold pressure and and extra 30kw up top. Makes for a way safer setup. It just annoys me that one must choose between a T25 .64 turbine housing and the next thing up is a T3 .82 with nothing in between. A T3 .82 divided housing for the 6258 through to 7670 would be just SO WINNING!

[Lithium]

^{E&H Motors in NZ have just released results of their testing with a twin scroll GTX3076R versus a twin scroll EFR7670 on their 2litre STI track car - worth noting that these results are not "all in", they have a stronger motor which will be used for that in future. From what the owner/tuner says it seems the EFR is much nicer to drive, and it sounds a bit like the EFR was seeming more eager to keep making more power.}

^{Dyno plots:}

[Nee-san]

it goes from under 100kw to over 300kw in 1000rpm

[Lithium]

It'd be an awesome ride, eh? I'm not sure how you could expect that to be smoother while being able to make 300kw by 4500rpm using only 2litres.

[R31Nismoid]

Pity they don't have GTX overlays @ the lower boost levels, and even a GT3076 for interests sake

[Lithium]

I think it was just that they were aiming for an EFR7670 from the start, and ended up getting a GTX3076R to get going because of the huge waits for getting an EFR - or something to that effect. The test wasn't to because they were doing a shoot out, more just a result of having both turbos.

I know they've had a twin scroll GT3582R as well, I might see if they ever tried that on the Subaru....

[Lithium]

Seems the EFR turbos don't need E85 to make good numbers - another Kiwi lad had his RB30DET R32 GTR tuned running a .92a/r twin scroll EFR8374 today on BP Ultimate, 462kw @ hubs on 20psi... full boost by 3300rpm.

Not too shabby!

[GTScotT]

Nice!

If only using one of these turbos was realistic. Waiting forever and having a questionable lifespan is very off putting.

Not that Id be at all interested anymore, owning a T3 6boost now -_-

[Lithium]

Very nice! For the SR20? What trubro is going on it?

The life span of them don't seem to be a problem since the foundry change, I actually know of a few people using them - a 550whp STI I know has been using a 7670 lately with no issue, an EVO track car over here has also been using an EFR8374 and it has been performing excellently

[GTScotT]

Yeap for my SR. My DET block is down at the machinist right now, im waiting for a call to tell me what size slugs to order.

Having done as much reading as possible into readily available options I couldnt go past a simple TD06. The FP 73HTA wheel apparently needs a bit of energy to be turned and isnt likely to be as responsive as the old 20g item (more or less making it useless for me as I want 270-300kw). I also found a number of resources from people saying they had owned 3071 and TD06 SR's and found the TD06 to be a lot better matched.

So yeah, logical deduction lead me back to a simple kando TD06. $560 later and its crackin.

Sorry peeps, back to BW EFR

[Lithium]

I wouldn't have (don't think I did) ever suggest the 73HTA for yours anyway - I reckon a 68HTA would have been great. I also lean towards TD06-20G vs GT3071R as well. Shame BW aren't doing EFR6758s in T3 though, I reckon one of those on an SR20 would be mental.

[GTScotT]

I did try and acquire a 6758 on a number of occasions but was never in the right place or time

It should be fun times ahead though. Birth of le angry SR.