Here is an Rx7 we built in house;

Small street-port( stock primaries, slightly later closing duration secondaries, exhaust ports matched to sleeves)
It is run on E50 with an Adaptronic E440D wire in model( with a flex fuel sensor)
Bosch 550 primaries, ID2000 secondaries, Aeromotive 340lph pump
Rx7store Greddy knock off FMIC( previously installed when this car was on the stock twins)
IGN-1A coils in direct fire with NGK race plugs
ACT street-strip clutch
hot air intake directly off the turbo( no room with the FMIC and stock pop ups)
Our 7670 IWG kit with 3" downpipe, high flow catted midpipe, and apexi n1 catback.

There is a dyno sheet with and without the cat. Cat only made a 150rpm difference in boost response, but affected the top end power quite a lot(limited max boost).
These runs were done with the OE BW medium actuator and EFR boost control solenoid.

I ran the boost up high in the midrange to give the car as much punch as possible for the street. I could not get anymore than 21psi out of it even with 7 turns of preload. Chances are we will do a turbosmart actuator upgrade and a muffled midpipe in the future and run it higher with summer blend of E85.

Car is really a blast to drive on the street. It is by no means a highway monster, for those looking for that you should move to the 8374 or 9180. We have a bunch of video on the dyno and street we are uploading, and preparing another 7670 car for a dyno early next week.

 

Very nice!

This EFR 7670 on your smaller diameter runner manifold made 15ftlbs more torque @ 2,000rpm and then up to 30ftlbs more torque @ 2,500rpm than my big runner T04Z manifold.

By 3,000rpm it is running slightly less torque- but that will probably change once you get the higher boost WG actuator in and get the boost ramping up faster as well as hitting a higher target.

I'm not sure how much affect the E50 had and how much was the smaller diameter exhaust runners, but that is some great sub 3,000rpm torque for a rotary!

Once you get your high boost actuator on their I bet the midrange torque will wake up and not drop off till 5,000rpm.

 

How far out rpm wise are you running out of breath?

 

What happens after 7000rpm?

 

It very slowly comes down in power, like any stockish port engine with a small frame turbo... It does not nose dive if that is what you are asking... I didn't save any other dyno sheets. I have another one to dyno in a week and I can do a full pull to 8k and record it( I did take this engine to 8200rpms previously, I just didn't save the sheet).

 

Thats a lot of area under the curve. Looking forward to seeing a graph run out to redline.

 

I have the pump gas, stock port, and stock cat car ready for the dyno. It makes 10 psi by 2700rpms in 4th gear, and 15( max setting) at 3k rpms.

 

When's it hitting the dyno??

 

I took a little video of the pump gas, fresh stock port, stock cat EFR IWG 7670 car today as I wrapped up the street tune;

https://www.instagram.com/p/96aKRww1...en-by=turblown

 

Awesome

 

Weather finally cleared and up and I had a chance to finish this pump gas, stock port, stock cat 7670 iwg car..

We are wrapping up another 8374 IWG car too..

 

That's really nice for stock cat. Good all around street car.

 

Think you could get that power band to stay high on the 7670 by moving to a 3.5" downpipe etc?

 

I had the same issue where even at low boost on external wastegates the boost would drop in the upper rpms (full 3.5" exhaust w/ 1 muffler).

I assumed it was because of my high priority WG placement the exhaust manifold pressure was keeping the WGs open in the high rpm.

I was thinking it could be solved by using the 2 port WG method (boost on top of diaphragm with bleed off) & boost on bottom of diaphragm).
----

It has caught my attention that every EFR 7670 I see is doing this though at high and low boost.

On high boost we are just coming up on the flow potential of the compressor (so boost naturally drops), but on low boost that same choke flow CFM should be available at lower boost with a higher shaft speed.

Any ideas out there?

 

I do not think the torque curve will ever change shape on the 7670. One can raise the power by adding more boost, but this torque curve is very typical of a turbine wheel this size. Look at my previous post comparing with and without the high flow cat( flex fuel car).

This is the reason we developed the TD series turbochargers, and later the TDX. The 7670 torque curve looks very similar to a GT35R. Once you put a bigger turbine wheel ( we moved to a 74mm turbine wheel in our TD turbochargers- GT35R compressor section). The Garrett gt35R uses a 68mm turbine wheel. This allowed the torque curve to stay a lot flatter past the 6500rpm range, and allow much more power in the higher RPMS above 18psi. The 8374 is identical in wheel sizes compared to our TDX62. Or TDX57 would be like a 7674.

 

Dyno sheet attached is from our full cast 7670 kit on pump gas. Street ported engine by Lucky7Racing.

13.6 psi; 377rwhp/298rwhp torque

 

Nice!

The boost did not drop, so it must have been my high priority EWGs being forced open with exhaust manifold pressure when I tried low boost runs and my boost dropped at high rpms.

This dyno shows what we would expect of a 57mm turbo on a 13B with a bit more down low and ofc that amazing EFR turbo response which you can't see on a dyno.

BTW, that chart would look way more impressive if it was re-scaled!

 

EFR 7670 IWG dyno result, car is a 94 FD built for autocross. The car was tuned for high boost with 110 race gas. Boost at 17psi, it bled to 15 psi at high RPM.

-Turblown EFR 7670 IWG kit with 3" downpipe, new cast shorty turbo manifold
-small street-port
-stock 550 primaries and 1600 secondaries
-stock coils with twin power
-NGK race plugs 105
-Greddy stock mount intercooler
-Custom 3.5" titanium exhaust with 22" Burns Stainless 6" size muffler

 

It looks similar to the results with stock twins to me. Clearly no power as for small exhaust wheel on that 7670....

Best,
Iwan

 

James I cannot remember, do you have the oem b medium actuator or a turbosmart unit ? Are you using a boost controller? This turbo will hold higher boost up top with a controller or more preload/stiffer spring etc. Probably not necessary for autox however...

 

I was there for the tune this past week and your exhaust sounds great. Keep up the good work.

 

Hey man, do you have a comparable dyno of your setup? I am probably wrong, but I thought your setup was not able to maintain boost up top.

 

I just noticed something.. .Is this dyno dynamics in standard or shootout mode(dynojet settings).

If this is in standard mode you are making near 460rwhp on a dynojet!

 

I have the OEM b medium actuator with no boost controller.

 

I believe the Dyno Dynamics was set on standard mode. Chris Ludwig was the tuner.