IRP EFR7670 Low Boost Dyno Results
 

Had a chance to tune another fd we built with our EFR7670 single turbo kit. Relevant specs on the build are our Stage 3 ports, RX Parts seals, AEM Infinity ems, IGN-1A coils, and our fuel system with 725/2000cc injectors. The car put down 378 wheel hp and 359 tq at only 13.8lbs of boost on pump gas alone. The car does have meth but we wanted to see what it could do without it. The turbo responds instantly and boost control is rock solid with our equal length stainless steel manifold. I believe this turbo is the ultimate replacement for the stock twins. This translates to a super fun machine for the street, autocross, or whatever you choose. Oh and this car has power steering, ac, and a catalytic converter so you can beat on it all day and still take the wife out to dinner after.

Nice. what is the difference between the ports on this engine and the port you did on prtrhahn engine?

Mighty impressive. From the graph it appears that at 3000RPMs the car is already at ~180RWHP. No need to downshift to pass a car... Me want

Its easy to build a car that puts down peak hp numbers. What's more difficult is to put together a well-sorted setup that performs well in a wide range of situations. Had a chance to put some street miles on this car and I can't get over how enjoyable it is to drive. I'd be more than happy to build you a kit if you are interested.

Oh man don't tempt me! I just spend a pretty penny getting my turbo rebuilt and manifold reinforced so there is no way the wife is green lighting it. I wish I would had seen this 1.5 months ago :(

For anyone that is thinking about this kit, look at the dyno that he posted. Compare it to others and see the area under the curve as well at the HP in the lower RPMs. This thing is fucking badass....

Haha you could always sell your current kit:ylsuper:

I tried to sell my kit earlier so that i can buy this kit.

If I plug the numbers into matchbot for 4000rpm (250whp @ 13psi) ..... you have to have 125% VE to get that much wheel power (assuming 40hp drivetrain loss) . Can someone explain how that is possible ?

Compare with the14psi log , same turbo ,on a dyno dynamics :
https://www.rx7club.com/single-turbo...esuts-1088491/

Almost looks like the rpms are wrong ..... maybe not done at 1:1 gear ratio ...

Matchbot is for piston engine VE's. Not rotary engine's

Ve is Ve no matter what engine it is . The parameter that changes for a rotary is BSFC and I was being generous with that even .

Its still more realistic than the dyno put out by a certain other high profile vendor on here for the same turbo,, 400+ at 12psi or something. Im guessing its just optimistic dyno figures, either way though, both look like absolutely killer setups.

I'm not sure how far you should trust the matchbot orr even the compressor maps anyway. I pretty much chose the 8374 over the 7670 because the former appeared to be more efficient at lower boost than the latter, ,, these dyno results coming out now kind of contradict that.

instead of questioning the results perhaps the theory should instead be questioned :p

That would be a good point if we were talking about a 'theory'.

400+ at 12.5psi with a half bridge and E85 on a dynojet = maybe 340 for a stockport on pumpgas and a dyno dynamics . I have more issue with the above dyno than the 400 one.

Ok my bad. Didnt see the part where it said "half bridge"
Still I'm very impressed with the low boost output on these turbos now. More efficient than i thought.
Stupid question; How far wrong would it be to take the estimated N/A power output of a given engine/port and multiply it by the pressure ratio for an estimated turbo output? Assuming everything is pretty efficient?

The main point of a dyno is an instrument for tuning. Comparing dyno numbers of different cars between different dynos is not accurate. Each dyno reads differently depending on the type, calibration, and how the user operates it. Ours is always super consistent and the power numbers always correlate with the setup of the car being tuned. That being said, a Mustang dyno typically reads 12% lower than a Dynojet because of the way it measures power. Dyno Dynamics tend read even lower in my experience.

Exactly ... I have seen this , and that is why I'm questioning the numbers as they seem at odds with other results for that same turbo and dyno. Is there any chance the pull was done in 3rd instead of 4th ? The peak power rpm looks too low .....(by about 1000rpm)

I've been eyeing this kit on the IRP website. Can I run this turbo kit with my current fuel setup? Currently i have 550 primaries and 1300 secondaries, Supra TT fuel pump, oem FPR, HKS Twin Power, managed by PowerFC+boost kit. What is the the power potential when i hit my limitations? Stock port 13brew engine.

Yes you can. However if the 1300s you have are modified stock 850s, I recommend you upgrade them to a more modern injector. We stopped running them many years ago because they had a high failure rate. We've had a bunch leak so we stopped installing them or tuning them. To me its not worth the risk. I recommend a FFE FD stepup kit with either ID or FIC injectors (bosch ev14 based). I can set you up with the fuel kit starting at around $700 depending on what injectors you prefer and it includes a regulator.The 7670 tops out around 400whp on a rotary with insane response. If you want something that hits a little harder, the 8374 is a good choice for 400+ with a small spool penalty.

How much less power do you think this would have made on stock ports? (Trying to decide between this and the 8374 for my stock port motor.)

About 15-20hp depending on port size. I will say the 8374 is a better choice if you want to approach and exceed 400 hp. The 7670 is a great replacement for twins without loosing response.