Update. Customer installed a new street ported engine and Xcessive LIM. Same turbo did a best of 460 whp and 427 lb/ft on the Dyno Dynamics. Peak boost of 20 PSI, falling to around 18.5 up top. That seems to be the limit of the little 55mm compressor that could! FWIW, that should translate to around 515 Dynojet.

The streetport shifted the power slightly to the right, but the area under the curve is fatter. Dyno printer is broken. I'll post up a pic of the screen when I have time.

Wow, that is amazing torque.....can I please haz?

This is the first time Ive seen this thread... Those are very impressive numbers because it's usable power. That car must drive amazing. 275+ whp at 4k is almost unheard of for an FD.

What non-custom turbos out there produce similar results?

What rotors is he running? stock FD? Some of the other SSM guys are running S5 NA rotors....

Hopefully they wont mind me posting. No tricks, just the standard FD rotors.

Dang, I was going to have fun with this. :lol:

My bad.:) I figured this thread and the build thread would get more attention but I dont think a lot of guys with bigger turbos........or motors:nod: want to acknowledge what can be accomplished with a nicely sorted out car.

I talked to him in huntsville several years ago at the time I am 99% sure he said hi comp rotors, stock ports, 19psi, small turbo, said he wanted the torque of stock ports.

It was a stock reman before I BUILT HIS ENGINE. Its definitely 9.0 rotors.

https://www.rx7club.com/3rd-generati...usings-976907/

That is the exact engine in his car. No tricks or secrets. The credit goes to the owner and tuner. Owner knew what he wanted to accomplish and how to accomplish it.

Double post, iPhone strikes again.

True. No tricks and stock rotors. My plans early on were to use NA rotors back when I was in Huntsville but I did not see a need for them at this time since I was getting good results with the 9.0 rotors. But the credit goes to the engine builder and the tuner. The owner just installed and drives.

So far the engine set up is doing well and the power and torque is working great for its purpose.

The "no tricks" motor did great at the Solo Nationals last week as did the pilot, Carter T.

Super Street Modified (SSM)
Pro Solo Finale 1st
Pro Solo Year-end Class Championship 1st
Solo National 1st

This was the first time in 7 years that the Texas 3-rotor did win the SSM Pro Solo Championship....not an easy victory, takes some luck/no car problems/super driving.

I have seen better numbers in a rew engine. My 13b-rew BP engine with a T04Z with E85, had 20 psi by 3000 rpm, and about 350nm at the same rpm, and 550nm at 5200 rpm. It dynoed 534rwhp at 20 psi ;)

And had about 250 rwhp at 3200 rpm :)


But great numbers on such a small turbo :)

JT

^^Where've you been?!

Congrats!!! Also he is saying the 3 rotor did NOT win. Mark up another victory for a properly setup 2 rotor. :)

This thread helped inspire me to buy a little baby turbo for my FC!

What did you go with?

EFR 7670 T4 1.0AR

Its going on an HKS tubular manifold which has short tapered runners.

Same or smaller than my BNR Stage4 hybrid, but I think being able to run high boost in the low/midrange is going to give it a different shape power curve and it will have better transient response.

Those EFR turbos look to be a very interesting fit. Not sure about how good the internal WG is though. Let us know the results!

Sorry, I wasn't brave enough to test the EFR exhaust housing with the internal wastegate as I never won the battle against boost creep on my last turbo set up.

I was tempted to try the internal WG along with using an external WG, but I think I will just crank the boost up on this build with race gas instead of trying to run low boost and pump gas.

actual race gas? or e85? I've been tempted to move to e85 especially with the 9.7:1 rotors...

Unfortunately, I can't get E85 anywhere near where I live. I think the closest is around 300 miles away.

I am thinking put 5 gallons 116 leaded in at home before I fill up with 91 octane.

Tetraethyllead is nasty stuff, but it will raise the octane level up way out of proportion to the 1:3 mix thereby offering savings over something nicer like 110 unleaded.

I will keep an allen key in the car so I can dial back my pop-off valve in case I have to drive around on 91 octane.

I've done this before for a season.

I think you're going to really like that turbo! I've run it's cheaper cousin, the s256, for a season of solo2 now. I've got the 1.22 housing, old aspec long runner manifold, 3" exhaust, and an overly rich tune... Despite all that the turbo is still decent for solo, a properly setup EFR will be awesome.

What happened?!!?

Still running strong. Changed to 3.5" exhaust and response is better. Turbo is immediate, only ever notice lag if i botched something.

Having never driven an efr turbo but seeing the dyno results i still think it would be better, but for this size turbo on a rotary could be diminishing returns. Although for a serious SSM car it would likely be right at home. My car is far from a competitive SSM build, could be a second or more off if driven well, but i think most of that time would be gained in aero and better dampers. The s256 for the money is great.

EFR 7670

I did my low boost tuning Friday and hopefully will finish high boost tuning Sunday or during the week.

The spool is really good, full boost between 2,500rpm and 3,000rpm depending on boost.

I had a mismatch of springs in the wastegate so they were waaay to soft (open @ 7psi). I have 13psi springs in now so hopefully response is a little better.

We did some 28psi pulls up to 3,000rpm before we had to stop because of a melted dyno strap.

369ftlbs/240rwhp at 3,200rpm @ 28psi boost on a dyno dynamics.

I have never seen a 13B with so much low rpm power.

369 lb/ft at 3200rpm??? Thats very impressive. This makes me really want to go for the EFR IWG turbo

The closest equivalent BW EFR model is the 7163 Indycar turbo; about the same compressor (57i/71e), slightly larger 63mm turbine, 0.85 A/R or 0.80 in a T4 twin scroll. Given the recent results of the other larger EFR turbos I have to wonder if an EFR 7163 would set record low rpm tq/hp numbers that nobody ever thought was possible?



.

Given the recent results of the other larger EFR turbos I have to wonder if an EFR 7163 would set record low rpm tq/hp numbers that nobody ever thought was possible?

Yes, that is the dream turbo set-up for my FD. Sequential twin EFR 7163.

Not only does the 7163 have less mass/leverage and favorable compressor map for low rpm, but my adventures with mis-machined turbo housings tells me the mixed flow exhaust wheel will spool like a madman on the rotary.

This is what I managed in my FC with EFR7670 on an old HKS T04Z FD manifold modified for dual 44 wastegates.

This is boosting to 26psi and then starts to fade after ~6,000rpm down to 20psi by redline. I don't know if the boost fade is because I am running 13psi springs in WGs (so I can run pump gas on street) or if the little compressor is out of flow at 6,000rpm.

Engine is early opening street port with near stock closing, 8.5:1 rotors.

https://www.rx7club.com/attachments/...s-efr7670x.jpg

he only has a single Precision turbo which I perceive to at least be equivalent to the EFR 7163, and seems to be doing better than your 7670 setup

(fast-forward to 0:16 on the vid)



granted you claimed not to be fully tuned on the top end, but in general the 7670 seems to have a more peaky Pr - mass flow relationship than some of the other sizes ...

The Precision 55mm wheel is -
50 trim
Wheel Inducer: 55mm
Wheel Exducer: 75mm

Turbo: Custom Precision Turbo HP5530SP with .78 AR T3 exhaust housing twin scroll, the exhaust wheel is a 60mm/84trim.

I don't think the 71mm exducer EFR7163 can move nearly as much air as the 75mm exducer compressor of HppRX7s set-up.

I think HppRX7's turbo is closer to the 76mm exducer on the EFR 7670 that I chose. Still, quite a different turbo!

It is interesting to note how similar the power curves are despite the very small 0.78AR T3 exhaust side with 60mm wheel on his versus the larger 1.04AR T4 exhaust side with 70mm wheel on mine.

His smaller turbo makes MORE top end power, but that is likely due to my boost dropping from 26psi to 20psi on the top end and the tuning.

I think a EFR 7163 would be a bad ass 300hp turbo on a peripheral exhaust port rotary, but I don't see it getting into the 400hp range. Maybe on a Renisis where you don't lose so much of the compressor map out the exhaust port.

We should also mention that you can't compare dyno figures as it is very well known that MOST workshops enjoy correction, loose straps etc etc.

just by the numbers the Precision is a hybrid 3076R, I don't doubt that their impellers on either side flow different than the Garrett though given the result

HppRX7 Precision 5530
55.0mm inducer
76.0mm exducer
60.0mm turbine @ 0.78 A/R EWG T3 divided
HC in^2 area ratio: 4.383/5.358 = 0.82

Theoretical BW EFR7163
57mm inducer
71.0mm exducer
63.0mm turbine @ 0.85 A/R EWG V-band or 0.80 A/R IWG T4 divided
HC in^2 area ratio: 4.832/5.046 = 0.96

Blue TII BW EFR7670
57.2mm inducer
76.0mm exducer
70.0mm turbine @ 1.05 A/R EWG
HC in^2 area ratio: 5.965/5.507 = 1.08

to be honest Blue TII, you have your own thread and I didn't post here to discuss the 7670 in general or your situation in particular. I'll be happy to discuss it over there instead if you like.

to be honest Blue TII, you have your own thread and I didn't post here to discuss the 7670 in general or your situation in particular. I'll be happy to discuss it over there instead if you like.

I was inspired by this thread to try a smaller turbo for auto-x and stated as much here. I re-entered the discussion 5 months later because of your comparison of the original poster's turbo to the much smaller EFR 7163.


The closest equivalent BW EFR model is the 7163 Indycar turbo;

Good luck with that! 7163 is an awesome turbo; I will take two of them. :nod:

Well, If I could get in the garage and finish my new project I might have some new numbers to compare with. I will be changing a couple of thing to say the least. I am just now trying to track down a couple of boost issues ( lack of) and I should be able to get on a dyno shortly after.

This is the set up I tried to get going before 2014 Solo Nationals but had to abort a week before and put in my tried and true Precision "the little turbo that could" back in.

Thanks for the all the in site from everyone. I always second guess my set up after reading some of the posts. lol.

No truer words have been spoken