[Closed] Borg Warner Efr Series Turbos

[BakemonoRicer]

Geoff,

Does the EFR7064 EWG with A/R 1.05 still retain the Investment cast housing.....

Or does it get the sand cast housing like the internal wastegate version?

[GTScotT]

Stock p11 cams have a fair bit of overlap so I guess that lowers dynamic compression and doesn't help make power.

I'll try pull the exhaust off tomorrow and check it out. I guess if I can remove a restriction from it I'll see boost rise a bit higher due to less back pressure since I run open loop boost control.

You should definitely consider changing cams or fiddling with timing on these. If you haven't already I would be advancing the exhaust cam at least 4 degrees to try and reduce that overlap. How you will test for valve contact on high lobe before actually running it though, I have no idea.

Within a few hundred RPM I have a comparable result to you, except mine has more midrange and I am running a far less exotic setup. GTX3071R, S14 DET with non VCT cams, 98 ron, 295rwkw peak, 280kw mid 4k on a DD roller. I attribute my result to the cam profile (256/11.5 Poncam).

For a VET setup with functional VVL, E85 and a EFR 7163 I think there is more to be desired. I would definitely visit the cam profile, and/or the timing. Remember to reduce overlap by advancing exhaust and use the intake to determine your powerband. In this case I think the little EFR is getting wound up a fair way and even the intake cam could be advances 2-3 degrees. Remember to offset whatever you advance the intake to the exhaust when you consider overlap.

Hope this helps!

[XKLABA]

[email protected], you bloody lucky SR owners, that is a profile I dream about for my 26 heads

Advancing the exhaust cam increasing overlap will give a higher dyno reading but what does that do for the 1/4mile dyno, MPH

I never advance exhaust, I always retard it cause overlap mean very little compared to what happens at the other end

[nicknack]

Cam gears are advanced 2 degrees on the intake and retarded 1 degree on the exhaust. I guess that doesn't help with overlap, but we figured it'd be a pretty safe bet to widen the powerband a bit.

I think I will change cams but undecided on which ones to go. I'll look into it more

[nicknack]

Checked the flex join in my downpipe today and the internal braid is fine and 3" diameter. The only other potential restriction in the exhaust would be my mid-muffler which has offset in and out.

I checked the turbine when the exhaust was off and it looks perfect.

[Full-Race Geoff]

Nick - an instance like this would be very helpful to have a turbo shaft speed sensor. This way you could correlate shaft speeds and determine if you had a boost leak (high shaft speed) or an exhaust restriction (low shaft speed)

The only other potential restriction in the exhaust would be my mid-muffler which has offset in and out. I checked the turbine when the exhaust was off and it looks perfect.

good idea to check that, and running without the muffler connected may easily help determine this - as compared to looking through it (seperating welds) or cutting it open for inspection

Cam gears are advanced 2 degrees on the intake and retarded 1 degree on the exhaust. I guess that doesn't help with overlap, but we figured it'd be a pretty safe bet to widen the powerband a bit.

I think I will change cams but undecided on which ones to go. I'll look into it more

Overlap is not a bad thing on high VE twinscroll 4 cylinder engines. In fact the best turbo 4 cyl race motors we end up with are typically using moderately aggressive all motor cams... i can not comment about your cam gear settings, but do not believe changing the cams would resolve anything

[BakemonoRicer]

After a few google searches it seems the 7064 (1.05 ext gate) has the sand cast housing now.

Kinda disapointing :(///

Investment cast 7670

vs

Sand-cast 7670

[Impulse-NL]

I got the sand cast on my 7670 too.

But going to get coated so it wont bother me that much.

Maybe got something to do with the price drop because I only paid 1350 euro's for it

[GTScotT]

[email protected], you bloody lucky SR owners, that is a profile I dream about for my 26 heads

Advancing the exhaust cam increasing overlap will give a higher dyno reading but what does that do for the 1/4mile dyno, MPH

I never advance exhaust, I always retard it cause overlap mean very little compared to what happens at the other end

Got that back to front man, advancing the exhaust cam means the exhaust closes sooner and the there is less overlap when the intake opens.

In my case reducing overlap worked wonders. More vacuum on idle and a lot more lively off boost.

[XKLABA]

Got that back to front man, advancing the exhaust cam means the exhaust closes sooner and the there is less overlap when the intake opens.

In my case reducing overlap worked wonders. More vacuum on idle and a lot more lively off boost.

Haha, oops, yeah got that back to front, meant decreases overlap

On my cars I advance intake and retard exhaust which increases overlap but gives results for the 26s

That an interesting result, what are the LCAs on your cams ?

[Piggaz]

Does anyone know if the 1.05 rears are interchangeable with the 1.45 rears on the 8374 and 9180?

[Sub Boy32]

I asked Geoff this a while back, the answer I believe was no due to the difference in the exhaust wheel size between the turbos, 80mm vs 74mm

[Piggaz]

What if they were to go between the same turbo.

You have a 1.05 rear on a 8374 and wanted to try a 1.45?

[Sub Boy32]

What if they were to go between the same turbo.

You have a 1.05 rear on a 8374 and wanted to try a 1.45?

Yes, that is fine, the wheels remain the same just the housings change.

The big problem is just buying an exhaust housing on its own, I wanted a 1.05 a while back and they just weren't available.

Not sure you would need to go to a 1.45, I'm already over speeding my 8374 on a 0.92 housing (132,000rpm, recommended max is 120,000, absolute max speed at 140,000) I think the 1.05 would be plenty on a 8374.

If you want more you would be best to go to the 9180

[Mick_o]

http://www.evolutionm.net/forums/evo-dyno-tuning-results/705932-martin-s-9180-efr-1-45-twin-scroll.html

Interesting that a 9180 with a 1.45 on a 2.4L evo is starting to choke?

[Full-Race Geoff]

Does anyone know if the 1.05 rears are interchangeable with the 1.45 rears on the 8374 and 9180?

yes, fully interchangable. The housings are direct plug and play for a given wheel size! we have these in stock if anyone wants to try

The big problem is just buying an exhaust housing on its own, I wanted a 1.05 a while back and they just weren't available.

we have the 0.83, 0.92 and 1.45 a/r exhaust housings in stock - no wait. only the 1.05 are hard to get at this moment

http://www.evolutionm.net/forums/evo-dyno-tuning-results/705932-martin-s-9180-efr-1-45-twin-scroll.html

Interesting that a 9180 with a 1.45 on a 2.4L evo is starting to choke?

Keep in mind - that is a fully built 2.4L race evo, with our AC compatible / Stock radiator kit. This uses the smallest runners and most restricted 3" downpipe for any kit we make. I believe there is >100+hp on the table by going to a larger diameter runner and nonAC downpipe

[Mick_o]

Thanks for clearing that up Geoff the 3" exhaust would be hurting things alot at that power level. The RB this will be going onto is quite extensive also. 2.8L stroker big $$$ head etc so what would be your choice on the 8374 Geoff?

[Sub Boy32]

Thanks for clearing that up Geoff the 3" exhaust would be hurting things alot at that power level. The RB this will be going onto is quite extensive also. 2.8L stroker big $$$ head etc so what would be your choice on the 8374 Geoff?

I'm not Geoff.....But for a 8374 on a RB28 with head and cams, I would say the 1.05a/r

[Piggaz]

I'm not Geoff.....But for a 8374 on a RB28 with head and cams, I would say the 1.05a/r

Would you consider jumping upto the 1.05 on your 3.0?

[Sub Boy32]

Would you consider jumping upto the 1.05 on your 3.0?

If I was going to do it over from the start I would put a 1.05a/r on it.

......however with the response and power I have now I don't think I'd change anything, if I wanted more than 650whp (98 pump gas) I would just go to a 9180 as I don't think I will be able to squeeze much more out of the 8374 even with a bigger exhaust housing.

Edited January 24, 2015 by Sub Boy32