has anyone used one of the EFR internal wastegate turbos yet?

i would love to switch to a simple IWG setup (i am running dual 38mm MVS gates with water lines right now, recirc'd into the downpipe) really just to simplify...

 

So far it seems like people have been talking about them for a while but nobody has been willing to risk the time and money on a setup that might not be able to control boost well enough.

 

yeah all the vendors are promising big things but so far its all talk and no chalk.

 

a few fd's are IWG, but no one is sharing anything yet . On the last page of single turbo setup one of the guys is running an IWG, but I think he isn't quite finished. I'm curious as well and hope to hear good things.

 

I'm still building this turbo set up but thought this might help at least with fitment questions, I'm running the EFR 7064 IWG'ed with EFR 8374 wastegate bracket on a Full Race manifold (custom made, they used my car as the test bed for the manifold) so if you have any questions just ask.

 

Here's a shot of the turbine side of things.

 

az93fd, that looks good!

i'll be looking foward to seeing if the wastegate keeps up. i am assuming it will...


does anyone know if the rickshaw FD guy is running an IWG or EWG?

 

Why run such a small turbo? 8374 is probably the smallest turbo that I'd run with a 13BREW, the response and spool should be amazing..

 

Talking with Jeremy from Full Race with this A/R I should be good for around 450 hp out of the turbo. Had I gone with the EWG 1.05 A/R I would've been good for around 600 mark I think.

 

I didn't want that big of a turbo, plus I should see some really good response times on spool up.

 

BW EFR 7670 COMPRESSOR MAP



there is a natural tendency to look at the eastmost line for max delivery. in the case of a number of BW maps the plots end at 65%. most Garretts end at 60%. lets look for a 60% delivery number. that would be further east. how far? hard to say BUT note the RPM lines. when they go vertical that means the turbo is maxed out.

let's assume you like many rotary guys will run 20 psi max. that is 2.36 pressure ratios. find 2.36 on the Y scale and extend it all the way til it hits the (pretty much vertical) RPM line.

that'd be 61 pounds per minute which is max flow at 20 psi.

61 X 14.471 = 883 CFM / 1.92 = 459 SAE rotary rwhp

based on the RPM plot max flow on the turbo, at an undisclosed efficiency, is 65 pounds.

65 X 14.471 = 940 CFM / 1.92 = 490 SAE rotary rwhp

yes, 65 pounds flow on a piston engine is 600 hp but not on a rotary. 490 is tops.

the turbo compressor wheel IS quite productive for its size.

BW EFR 7670 5.524 average sq inch area

GT35 6.386

howard

 

Thankfully I'm only looking for 425 to 450 rwhp then, guess we'll see what numbers I'll put down here soon enough.

 

all the compressor info is great, and i appreciate it, but i'm more concerned with the internal wastegate.

i'd like to run the EFR 8374 IWG, and i'm wondering if that internal gate is going to flow enough on a rotary. i cannot find any info on this.

 

With that small a turbo, you'll really suffer where the 13B is suppose to shine, in the higher rpm/boost range. It's all about the trade off, I'm sure the response is insane with the 7064, but limited up top. I have a feeling that you'll at least upgrade to a 7670 later..

 

Upgrade, maybe...maybe not honestly. I just posted in here to helpout honestly, I have a feeling I'm going to get exactly what I'm looking for out of this application.

 

" I'm running the EFR 7064"

i thought you were running the 7670... post 11 Compressor Map is the 7670 turbo.

post 8 becomes more significant...

"Why run such a small turbo?"

the 7064 is small... featuring a 4.632 sq inch compressor.

compressor map shows 52 pounds per minute tops at 20 psi 392 hp and that is at the wall rpm-wise. if you look at the efficiency islands you will see that the 52 is probably a long way from the 60% acreage. meaning in the real world you won't see anything close to 392 at 20 psi.

absolute max on the turbo (33 psi) is 55 pounds or 414 rotary rwhp.

do keep in mind when most turbo outfits quote hp for a given turbo they are probably talking PISTON hp. you need to divide that by 1.3 to get rotary hp.

EFR 7064 Map

 

Jacob, sorry don't have any info in the internal WG. my guess is that Geoff would be the best info source. i do feel that BW probably properly sized it as they are pretty good at engineering.

is there a reason that a rotary engine would have diff WG requirements V a piston?

howard

 

howard, i was thinking the IWG would have to waste more exhaust on a rotary than on a piston engine to maintain a certain boost level, but maybe that's not the correct way to think about it?

 

Rotary engines have very high corrected mass flow through the turbine section due to high exhaust temperatures and general ability to move air. It takes a lot of wastegate to keep from overspeeding.

The 2nd gen Rx-7 turbo engines had a twin scroll turbo with internal wastegate drawing exhaust from both scrolls. It was very ahead of its time. It wasn't as optimized as modern twin scroll internally gated turbos because they didn't have the same computer simulation tools we have available now.

 

Holy **** sorry for chiming in on anything now! Wow! I'll keep my build to myself an what not.

 

hey az93fd.... no dis-respect to you. i felt it was important to set forth the turbo metrics so that everyone reading this thread would have the info and could make their choice. i can understand your objectives and you have a very efficient 21st century turbo. do keep us in the loop. also, you have probably one of the first internal wastegated manifolds which will be interesting. thanks for taking the time post your pics.

hc

 

Personally I am very grateful that you are posting your setup and details. It looks like it's going to be a great example of what the smaller version of these turbos are capable of, so kudos for thinking outside the box. I'm sure on the larger wheel turbos we will eventually have multiple examples of how they perform, but yours may remain unique, and provide valuable info. Please post back about how things work out for you once your car is done.

 

I have to agree with him, I was glad you posted in here. I plan to go IWG, so it's nice to see someone doing it and on a smaller turbo. Not everyone shoots for huge hp, so it's nice seeing what the smaller turbos are capable of on the rotary. I'm sure it's going to be enjoyable to drive. Keep us posted please.

 

Please keep us posted on your EFR7064 project, az93fd. I think 300-400whp is a good goal. I've driven a Supra with ~400whp and it was plenty fast... I can't imagine needing more power in our lightweight chassis.

 

We've got a few of these leaving our shop this week. 7670 & 8374 units.