[Closed] Borg Warner Efr Series Turbos

[Full-Race Geoff]

A mate has an RB30 (aiming for nudging 600whp on E85) which we discussed turbos, manifolds, wastegates etc to great length without spending silly money and the combo settled on is a Airwerks S300SX 8375, .91a/r TS with a small tube twin scroll manifold and single large external wastegate.

for 3.0L and 600whp, the 8375 is too small - not gonna reach your power targets.. that 60mm inducer turbo maxxes around 530-540whp on a 3.0L engine. Instead, I recommend the 61.4mm FMW at the smallest (550-560whp max) and also the 64mm FMW would also be worthy of consideration for a 600+whp target on this size engine. The single large wastegate will not do this setup any benefit

Do you have any of these results you can share? There are others who I respect the opinion of who have stated they have found no advantage going between twin wastegates and a single large one - I get people asking me for input but this is an area that while I have some theory on, I've not seen two separate otherwise equivalent setups using twin and single.

the recent tests I was referring to was done by Jeff Evans at evans-tuning.com -- one test was a 900whp B series drag honda, the other a 500hp SR20DET. i will email jeff and ask for the comparison charts for you. In my experience FR has produced subarus with twinscroll single gate, sr20 twinscroll's w/ single gate and B series honda twinscroll single gate. Only the SR20 remains an option for our twinscroll manifolds, because customers request it (all others were discontinued). From my first-hand experience, i would not run a single gate twinscroll on my personal projects. I used to run a twinscroll gt30R single WG config on my SR20 beater, but since sold the setup and will be installing a 6258 iwg.

R_34 your call but if it were me with an RB20 and really wanted an EFR I'd look harder at the 7163 , I think it would have a more useful rev range unless the absolute top end is your goal .

^^^^agree

Have seen some EFR7163 results now, they are more like what I would have expected in terms of boost threshold - unfortunately there seems to be no magic, they DO produce very very impressive power for a 71mm OD compressor but in dyno overlays with an HTA3076 the HTA actually edges it out... and interestingly, the EFR7163 edges the HTA for peak power.

The transient response (like all EFRs) however is apparently awesome, but that will apply more to the full throttle/race type people and it won't help the low-down pull some might be after for RB20 road-ish cars. I guess there is no getting around the fact that it's a large trim compressor with a 57mm inducer

the singlescroll EFR7163 is available in a 0.85 a/r (which is pretty large obviously) but im surprised at your conclusion that a 76mm compressor GT30 based turbo would edge it out... its a bit early to compare but that has much more inertia than the 7163. In fact the 63mm mixed flow turbine wheel has almost the same inertia as the 58mm radial flow turbine wheel..

I based my ideas on what Geoff reckons the 7163 is good for power wise which from memory is 500 crank ponies . I'm not really sure what numbers a road race RB20 is typically good for but even that should be impressive in a race weight R32 GTST - provided the usable rev range is wide enough...Larger framed EFRs like the 7064 7670 etc have larger housings so they may let the RB20 be a bit more free reving over a 7163 but how much mid range do you compromise ?

yes, the 7064 does have much more exhaust flow capacity than the 7163 - so it can make more power and more boost in the higher RPM. However in terms of overall transient response and boost response that is tightly linked to throttle position, the 7163 will take the cake... particularly in the twinscroll 0.80 a/r housing

My question is, whats a solution to having a fairly low gate pressure and still hold high? I mean, I have a low boost setting (14psi) makes about 300 or so kw, great for track. If I put a heavy spring in im not keen on 360++ low boost, which is more than enough on the track I think. But the trade is it'll hopefully pull 400 with ease. I run a greddy 50mm gate and eboost street. The t04z used to hold 22 solid. I assume this has alot to do with heavy rotating turbo and massive capacity.

if you want low gate pressure and the ability to hold high boost with an IWG - a 4port boost control solenoid controlling a sealed 2port vacuum actuated device could achieve that (Turbosmart tells me they are very close to having an IWG canister in this configuration for the EFR) as would an Electronic-actuator. Traditionally the easiest way is with an External-WG. I personally like to run the IWG's with as much spring as possible, since we have E85 readily available in Arizona. I acknowledge everyone wants something different so we are working on those setups also

From what I read EFR is expanding its range of turbine housings so they aren't all out yet . Full Race has welded T3 flanges on T2 7163 housings so that's a possibility .

I don't have any interest in GTX3076Rs because I reckon they have more compressor than turbine , closer to GT3582R airflow without the 35 turbines flow rate or comp housings too . I mentioned 500 crank ponies because Geoff reckons they are hard to beat in this range for response and transients .

agreed

For GT30 based I'd rather have a 3076HTA than the GTX version .

Im surprised you feel that way, its still a 76mm compressor on a 60mm turbine.. for that reason the only gt30 based turbo im fond of is the gtx3071R. to each his own!

Edited June 10, 2014 by Full-Race Geoff

[Full-Race Geoff]

one more post before i get offline for the day -- here is a 2.5L subaru, comparing EFR7064 twinscroll (blue) to EFR7670 twinscroll (red) - turbo was the only change

[Lithium]

for 3.0L and 600whp, the 8375 is too small - not gonna reach your power targets.. that 60mm inducer turbo maxxes around 530-540whp on a 3.0L engine. Instead, I recommend the 61.4mm FMW at the smallest (550-560whp max) and also the 64mm FMW would also be worthy of consideration for a 600+whp target on this size engine. The single large wastegate will not do this setup any benefit

To be fair, the aim wasn't that high power wise - so if it falls short it's no biggy, response is the main thing. This will be tuned on a Dynapack by the way, so we're not aiming for Mustang/Dyno Dynamics "whp" type numbers. From memory the FMW options weren't available when this turbo was chosen/bought, and the 62+mm turbos that were available looked like they would be too lazy.

the singlescroll EFR7163 is available in a 0.85 a/r (which is pretty large obviously) but im surprised at your conclusion that a 76mm compressor GT30 based turbo would edge it out... its a bit early to compare but that has much more inertia than the 7163. In fact the 63mm mixed flow turbine wheel has almost the same inertia as the 58mm radial flow turbine wheel..

The conclusion comes from a dyno plot, it's not a wild bet when the HTA stands up earlier on the plot than the EFR as in the earlier parts of it the HTA line is higher In terms of inertia, if you look at my post I did indicate I had no doubt that the transient response of the EFR would be the winner - but in terms of boost threshold potential the HTA has the edge in the only testing I've seen of it. The EFR's flow was very impressive, however.

You of all people should know that wheel aero differences mean you can't predict the performance of two turbos by only comparing the exducer measurement of the wheels only. By that logic a TD05-16G, 18G, 20G and a FP 68HTA would all spool the same and make the same power, 34GeeTeeTee on here went from a Garrett GT3076R to a FP GT3076R HTA with no other changed beyond the tuning to suit and every point on the powerband was up substantially, at times by a LOT, with transient response in a different league. That's the kind of response comparison you expect to hear between a GT3071R and a GT3076R, but without the big flow increase - and that's comparing two turbos with a 60mm turbine and a 76mm compressor

Not surprised you approve of the GTX3071R, I think it's probably one of the most worthwhile Garrett GTX series - most of them haven't moved me too much to be honest, they seem very impressive. I think you put too much stock in just the influence of compressor exducer size for trying to anticipate spool etc, it's fine when you have a bunch of different compressors which are the same trim (Garrett GT-series is almost like a big 56-trim party) but the HTA3076 only has .7mm more inducer and I'm picking a lighter (11 vs 7 blade) comp wheel which isn't partly design to be quiet. So far testimonies from people who have run each turbo come out very similar in response terms, except the HTA makes more power.

I think you mentioned a while back someone is doing an EFR9180 RB somewhere along the line - is that right? And any results yet? The EFR9180 is still something of a unicorn.... quite interested to see how it performs.

[omnigear]

ghetto question, cant just get a plate to make a twin efr work on the stock manis?

[Piggaz]

ghetto question, cant just get a plate to make a twin efr work on the stock manis?

Two chances of fitting those in factory position.

[Lithium]

Wonder if anyone can do anything cunning for these like the R35 lads have done for turning EFRs into boltons:

Stock R35 IHI turbos:

EFR CHRA versus R35:

Comp wheels:

Turbine wheels:

then some mysterious Frankenstein haxing stuff... results in:

[Piggaz]

Any results of that, Dan? Sorta like shoving GTX wheels in bolt on housings but going one step further. Potential cons using the EFR wheels?

[abr33]

if you want low gate pressure and the ability to hold high boost with an IWG - a 4port boost control solenoid controlling a sealed 2port vacuum actuated device could achieve that (Turbosmart tells me they are very close to having an IWG canister in this configuration for the EFR) as would an Electronic-actuator. Traditionally the easiest way is with an External-WG. I personally like to run the IWG's with as much spring as possible, since we have E85 readily available in Arizona. I acknowledge everyone wants something different so we are working on those setups also

Im running a greddy 50mm gate, with turbosmart e-boost street 40.?

[Full-Race Geoff]

Im running a greddy 50mm gate, with turbosmart e-boost street 40.?

you may consider trying a 4port boost control solenoid and/or a stiffer WG spring. the optimal solution in my opinion (assuming your header is divided) would be dual WG's on a 4port... but thats more work and expense than you may want to get into. Working at a fabrication shop, I sometimes take changes like that for granted

ghetto question, cant just get a plate to make a twin efr work on the stock manis?

unlikely, the stock manis really only work with stock-footprint turbos. EFR twins will likely need to be top mounted in the RB engine bay. Between the PS pump, AC compressor, strut tower and hoses/lines there isnt much room to work with, considering we also want (2) intake tubes, (2) charge pipes and all the associated plumbing

Wonder if anyone can do anything cunning for these like the R35 lads have done for turning EFRs into boltons:

then some mysterious Frankenstein haxing stuff... results in:

in order to do this, the EFR center section must be machined, to turn down the OD so it can fit into the R35 end housings. This requires disassembling the turbo and then rebalancing it (high speed core balance). Also, the R35's IHI housings are considerably bigger than the garrett T25/T25 housings so while I don't know for certain, i think this is a non starter

Edited June 11, 2014 by Full-Race Geoff

[Full-Race Geoff]

red line = EFR7163 (singlescroll) subaru EJ25, using E85 fuel

green line = stock turbo E85

without turbo speed date, i assume this 7163 is operating close to overspeed and this is every bit of airflow it can muster. However for a low VE 2.5L motor like the subaru EJ25 to acheive this performance is impressive. The build spec is simple and straight forward: stock OEM block with just manley pistons and rods, along with some kelford cams, spearco TMIC

Im planning to install a 7163 on my evo in the next couple of weeks, will be interesting to see what it puts out.

[sucram]

what housing is on that?

[Full-Race Geoff]

vband, 0.85 a/r external WG

[sucram]

would make a good street turbo even on a 2.0 on ulp

[Tonba]

I'd love to see someone put a 7163 on a smaller engine like the SR20. I think I would be fantastic.

[cobrAA]

one more post before i get offline for the day -- here is a 2.5L subaru, comparing EFR7064 twinscroll (blue) to EFR7670 twinscroll (red) - turbo was the only change

can we compare this figure to a rb25 ?

[GTScotT]

can we compare this figure to a rb25 ?

With a fairly large shift to the left I'd imagine. All dreamy and stuff though, no guarantees.

[Lithium]

I think EJ25s don't spool much or any different to RB25s from the results I've seen, though RB25s may flow better - neither motor are great at spooling turbos for their displacement.

[cobrAA]

Okay was just trying to make a comparaison with a RB26 actually lol.. My mechanic is convincing me to go single and thinking about a 83/74 0.83 or 0.92 IWG. or maybe the 76/70 for awsome spool. although i think i read geoff saying the 76/70 is a tad too small for rb26. If only I had a rb28 choice would be easier lol, it seems like the rb26 is torn between the max limit of the 76/70 and the 83/74.

My mechanic also told me that he only installed one EFR turbo but this one was IWG and had boost control problem. So, are the IWG great option on RB26 or really the EWG is better idea?

Edited June 19, 2014 by cobrAA

[Full-Race Geoff]

cobrAA -- the EFR IWG's have a large diameter wg flapper, and hence need stiffer spring than was originally called for. Turbosmart has their IWG lineup ready to go now and it uses the same springs as their EWG, so plenty of options there. I personally have had good results with the oem borgwarner 'stiff' actuator, but the turbosmart is a great option for boost levels above that

i think the 7163 is a bit small for a high boost rb26, as it can be overspun. Same with 7670. however they both provide excellent spool and response so if you use a shaft speed sensor to keep things in check you could be very happy with either on an RB26 - just be prepared to taper the boost up top. The 8374 comes on strong around 3300-3400rpm - so it might be bigger than you like, but i really enjoy it on the RB26 (its one of my all time favorite turbo/engine combinations, so much fun to drive). I am putting the 8374 0.92 back on my RB26 in a couple weeks, after i put the 7163 on my evo

Lith - i agree a 2.5L subaru EJ is comparable to a 2.5L nissan RB. one difference being subaru has longer length exhaust manifold, so those engines seem to be more affected by how hot the turbo/manifolds are at the start of dyno pull. here is a cold run (red line) vs 2 hot runs on that car (blue and green lines)

Tonba - we've got (2) SR20 guys who recently picked up 7163s, if i get any results i will post here. scott kuhner @ Insight is a fan of the 7163/sr20 combination he tested some prototypes for me last year

Edited June 19, 2014 by Full-Race Geoff

[cobrAA]

cobrAA -- the EFR IWG's have a large diameter wg flapper, and hence need stiffer spring than was originally called for. Turbosmart has their IWG lineup ready to go now and it uses the same springs as their EWG, so plenty of options there. I personally have had good results with the oem borgwarner 'stiff' actuator, but the turbosmart is a great option for boost levels above that

i think the 7163 is a bit small for a high boost rb26, as it can be overspun. Same with 7670. however they both provide excellent spool and response so if you use a shaft speed sensor to keep things in check you could be very happy with either on an RB26 - just be prepared to taper the boost up top. The 8374 comes on strong around 3300-3400rpm - so it might be bigger than you like, but i really enjoy it on the RB26 (its one of my all time favorite turbo/engine combinations, so much fun to drive). I am putting the 8374 0.92 back on my RB26 in a couple weeks, after i put the 7163 on my evo

thats way better than a pair of gt2860 that come on hard at 4k.