Borg Warner EFR Series Turbo's V 2.0

[R32 TT]

1 hour ago, welshy_32ZILA said:

Yes  1:1. How can't it be 1:1? 36psi on intake ~36psi in exhaust manifold. If emap was lower we cld push more boost till the emap rises all depends on where the tuner wants the ratio between map:emap.

 

Sorry what I meant by saying "it can't be" (when referring to 1:1)  was that that is really very good and not an indicator to me that the Turbine housing is a restriction.     Sounds to me then like its probably pretty good to drive! 

[usmair]

what the heck is an emap

[Lithium]

5 minutes ago, usmair said:

what the heck is an emap

Exhaust manifold pressure.   When talking about turbocharged spark injected cars 1:1 boost versus exhaust pressure at full power was pretty much the realms of drag car setups not a really long time ago, I have had conversations with people who actually have doubted it is possible to have equal exhaust pressure to intake pressure so managing to have a reasonable amount of response while not having boost pressure go past intake pressure is quite a big deal - albeit still meaning it is leaving a heap on the table.

 An EFR8374 making this much power with a 1.05 would have a scary amount higher exhaust pressure than boost pressure - if it was possible to even do it 

[Myskyliner33]

Picture of emap i did on AE86

[welshy_32ZILA]

15 hours ago, R32 TT said:

Sorry what I meant by saying "it can't be" (when referring to 1:1)  was that that is really very good and not an indicator to me that the Turbine housing is a restriction.     Sounds to me then like its probably pretty good to drive! 

I guess it depends on where u class map:emap your stopping point. Ie in my instance that's where we stopped and class it as a restriction. Obviously a few things could help the power figure. Better head/cam setup and trial of the 1.45 rear along with not having leaking tbs also. 

[GTSBoy]

I would suggest that limiting boost so as not to exceed 1:1 E/I MAP ratio is being far far far too conservative. it is not that long ago that a street turbo car would have 2 or 3 :1 ratio.

I would lean on it some more. Even a1.5:1 is absolutely free breathing in real terms.

[Lithium]

54 minutes ago, welshy_32ZILA said:

Ie in my instance that's where we stopped and class it as a restriction. Obviously a few things could help the power figure. Better head/cam setup 

That's a tricky one, though.  For the compressor to push air it needs force at the turbine to accelerate the turbine&compressor and move the air (which has a mass) - let alone to compress it.   That force comes from drive pressure, which is essentially the raw EMAP value you are reading.  If you do headwork to require the amount of boost pressure required to move x-amount of air it will reduce the amount of work the turbine needs to do to a degree, meaning a bit less drive pressure required - but the trick there is you have reduced numbers from both sides of the ratio.... so your EMAP reduces, but so does your IMAP and you COULD even find yourself making less power as a result of the reduced boost you have to run to keep the ratio at or below 1:1.

It's a bit hard to say which will reduce more, but if I were a betting man I'd be backing the cost vs reward benefit as not being anywhere near as rewarding as just using the turbine speed as the primary warning for overwork, and maybe relaxing your EMAP/IMAP ratio cut off back to even about 130% (which is still quite conservative imho) you will get much better gains than the headwork for no cost or compromise.  

Just my opinion, but it's become a conversation so I'm throwing it in there.  If you were happy with the current power level then thats all good, but if you are looking at spending a bunch more money to try and get more performance when the data suggests the performance is available comfortably with the current package - I'm not sure why you'd not use the obvious approach.   As @GTSBoy said - 1:1 is crazy conservative for most cases, and is more of what you'd see in they higher levels of drag racing where you have something you are looking to make MAX power so reducing forces and restriction is the priority, response is absolutely not.  

Edited October 16, 2019 by Lithium

[usmair]

I don't think the head is a major restriction as your setup is pretty similar to mine - my head is not ported and has baby drop in cams with basic springs/retainers.

It just means you need more boost to make the power.

Did JEM tune your car?

 

[welshy_32ZILA]

3 hours ago, usmair said:

I don't think the head is a major restriction as your setup is pretty similar to mine - my head is not ported and has baby drop in cams with basic springs/retainers.

It just means you need more boost to make the power.

Did JEM tune your car?

 

Nah mate Sean from what used to be EFI. He's now at Auto Care Centre in goldy

[taijohnsen]

My predicted MAP vs EMAP lolol

[R32 TT]

...have they finally got the 8474 up on matchbot have they?

[taijohnsen]

lol, no. This is my 7163 on a 3.0L ?

[burn4005]

And it's probably more than that as exhaust backpressure x turbine expansion ratio piles on pretty fast. And your matchbot input numbers for exhaust backpressure are probably quite low. 

[burn4005]

On 10/15/2019 at 5:49 PM, welshy_32ZILA said:

Yea running a kulig kit. I'm not too phased on the dyno number to be honest burn. Last time I rolled off the dyno with 460hp I was surprising people with nearly the same in kw. 

 

I totally missed the fact you were bleeding off a lot of boost up top.

I saw a post with 8474, 2.6l, 36psi and 500kw and thought it didn't add up. now I've seen the dyno sheet it makes a lot more sense.

Carry on!

Edited October 21, 2019 by burn4005

[Nosure]

7 hours ago, burn4005 said:

I totally missed the fact you were bleeding off a lot of boost up top.

I saw a post with 8474, 2.6l, 36psi and 500kw and thought it didn't add up. now I've seen the dyno sheet it makes a lot more sense.

Carry on!

Yeah it’s make sense. It only about 25psi at higher rpm. My one make similar HP on 25psi. But I got 1.45a/r housing, different engine setup and different dyno(awd).  At the end I set at 26psi 710awhp. And it is still more room for more hp if I use 4 ports boost solenoid.  For drivetrain safety I don’t want push more.  I think 1.45 will help and it doesn’t take too much response away.  

[Nosure]

Look closely. My one made 700hp is between 7500-8000rpm at 26psi.  
Welsh’s 2.6 peak power at 7300 around 30psi.  

I think the head setup make some difference.

the 8474 1.45a/r on road feeling is better response than my old 3582 gen2 0.83a/r.  And go faster for sure.    

 

[burn4005]

This is a good comparison as mine was also done on The pits Dyno. 8374 2.6 1.05ar.

490kw run was 190kpa (27.5psi) and I was limiting turbo speed as the 8374 was at 126k rpm, hence it nosing over. 

 

 

Edited October 21, 2019 by burn4005

[Nosure]

13 minutes ago, burn4005 said:

This is a good comparison as mine was also done on The pits Dyno. 8374 2.6 1.05ar.

490kw run was 190kpa (27.5psi) and I was limiting turbo speed as the 8374 was at 126k rpm, hence it nosing over. 

 

 

that's perfect comparison. so RB2.8 8474 1.45 made 525awkw on 26 psi 117krpm. 8374 1.05 made 490kw on 27psi 126krpm.  and if same engine same a/r housing  the response should be very similar.

is that rwkw or awkw?

[burn4005]

It was rwkw

[Nosure]

8 hours ago, burn4005 said:

It was rwkw

Still good power for 8374. 

Edited October 22, 2019 by Nosure