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Title pretty much says it all. I'm trying to figure out if that's something that can be done in a fairly reliable fashion. I want 400whp and I don't want to have to worry about where my next tank of gas is coming from. I can get 93 anywhere near me so that's what I'd like to tune for. Ideally, I'd like to stay away from meth/water injection too if possible.
Currently, I have stock primaries and ID2200cc secondaries with the Rotary Performance upgraded fuel pump. So the fuel system should be solid. Engine was rebuilt about 12k miles ago by Rotary Performance with 2mm goopy seals (as well as all other new seals) and stock ports. I have a PFS SMIC, 3" straight through exhaust from the turbos back. Everything is tuned with an Apexi PowerFC.
Thus, I'm looking to add the EFR7670 (internal wastegate and BOV) to replace the stock turbos. However, what else would I need to add or upgrade to achieve 400whp reliably? Is it time for ignition upgrades? What else am I missing?
Last edited by ItalynStylion; 09-01-16 at 09:30 AM.
I don't know if you have read this thread yet, but you would be pushing close to 20-25 psi for 400 RWHP, depending on dyno.
At that PSI, it would be tough to say it would be reliable under all circumstances. Since you are in Texas, the heat may cause undesirable issues with running that much boost.
Also, consider upgrading your intercooler. The SMIC is still a bit small and can still heat soak under high boost.
I don't know if you have read this thread yet, but you would be pushing close to 20-25 psi for 400 RWHP, depending on dyno.
At that PSI, it would be tough to say it would be reliable under all circumstances. Since you are in Texas, the heat may cause undesirable issues with running that much boost.
Also, consider upgrading your intercooler. The SMIC is still a bit small and can still heat soak under high boost.
Reading that thread cover to cover....taking a while. Lots of good info in there. Thanks for posting.
Thus, I'm looking to add the EFR7670 (internal wastegate and BOV) to replace the stock turbos. However, what else would I need to add or upgrade to achieve 400whp reliably? Is it time for ignition upgrades? What else am I missing?
In my opinion-
Add porting to make it more reliable at 400rwhp.
It will lower the boost pressure/heat the turbo has to produce to max its flow.
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On my FC with mild street port my peak power of 420rwhp Dynojet was made at a boost of 21psi.
I mean, I ran 26psi, but boost faded to 21psi by peak power (420rwhp) and then when the port flow maxed at 7,000rpm boost went back up a bit to 22psi to redline.
So, if you make an engine/peripherals that flows better the max boost will be even lower at max turbo flow.
Semi p-port, bridge or even beveled rotors and a good street port.
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The only downside is the added engine flow will put the peak turbo flow lower in the engine rpms.
As in, you will probably hit 400rwhp around 4,500rpm and stay at 400rwhp till redline.
Which sounds great, but feels like a truck because you have peak torque around 4,000rpm and then torque drop like a rock to redline.
You will find yourself shifting 5,500-6,000rpm to get back to peak torque and peak turbo efficiency.
After reading the 2 year long thread posted above, I have a much better understanding of things now.
For my current setup, changing the ports is not an option. I've already rebuilt the engine recently so we're not paying to have her opened up again unless I kill something and NEED to rebuild it. I should have mentioned that in my original post.
That being said, after reading your thread Blue_TII I think I'm on the same page as you with regards to peak power vs usable power. That's why I was interested in the 7670 from the beginning. Although the twins are great, the lull in boost as the twins cross over yields a situation that makes it easy to break the tires loose mid-corner when you're at the limit. Additionally, if I could stay in 3rd for longer on Eagles Canyon Raceway I wouldn't have to hit 2nd in some of the turns where boost hasn't come on yet. I'm wanting to achieve a more "NA" style powerband and I believe the 7670 is the turbo for that.
One thing I didn't see in your thread was the theoretical limit of the 7670 on 93 octane. I think most of your dynos were on race gas which isn't realistic for 99.99% of my driving as it's a second car that's driven daily. I guess I'm really interested in what the the upper limit for whp is but also the torque level I'd be seeing at 3,000rpm with the associated boost level.
Last edited by ItalynStylion; 09-01-16 at 12:02 PM.
Although the twins are great, the lull in boost as the twins cross over yields a situation that makes it easy to break the tires loose mid-corner when you're at the limit. Additionally, if I could stay in 3rd for longer on Eagles Canyon Raceway I wouldn't have to hit 2nd in some of the turns where boost hasn't come on yet. I'm wanting to achieve a more "NA" style powerband and I believe the 7670 is the turbo for that.
I used to have issues auto-xing my FD with stock turbos when I was in stock class because of the poor ECU driven 2ndary turbo transition.
I put the Hallman Pro-RX manual boost controllers back on wastegate and pre-control actuators from the previous owner and ran in ASP class.
With this set-up you can really adjust the twins for a seamless transition every time- very easy to drive.
The only reasons I would use EFR 7670 on my FD instead of the stock twins is the ability to run high boost for that massive low/mid-range rpm torque and turbo reliability and durability of a single turbo.
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One thing I didn't see in your thread was the theoretical limit of the 7670 on 93 octane.
Theoretical limit on pump gas.
I think you want to know the "safe" boost limit on pump gas.
This is subjective.
My 7670 did 420rwhp at 21psi (set to 26psi fade to 21psi by peak power).
Some people run 21psi on pump gas.
My 7670 did 412rwhp at 18psi (set to 22psi fade to 18psi by peak power).
Some people run 18psi on pump gas.
My pump gas setting did 315rwhp at 6-8psi (set to 12psi fade to 6-8psi by peak power).
Not many people run only 6 or 8psi on pump gas on a single turbo RX-7.
IRPerformance 8374 would be a better choice imo.
^^^ I have considered putting my 7670 kit on my FD with a 8374 turbo instead.
7670 is like the best sequential twins ever without the headache, the 8374 is like the sequential twins plus a bunch of power- without the headache.
Interesting. So with the 8374 I'd be able to run lower boost but make more power and still run on 93 octane? That might be worth it. The wife wouldn't be very happy about keeping a barrel of race gas in the garage...
Blue TII, I see you have your tunes (all of them) setup to start at a higher boost and then fade/taper at higher RPM. Why is this? Particularly, on your pump gas setting of 12psi, why not hold 12psi all the way to the top of the power band? Does the "safe" boost level change based on RPM?
Blue TII, I see you have your tunes (all of them) setup to start at a higher boost and then fade/taper at higher RPM. Why is this? Particularly, on your pump gas setting of 12psi, why not hold 12psi all the way to the top of the power band? Does the "safe" boost level change based on RPM?
It was not my intention, just the way it worked out.
I think it was because of my very high priority to the two 44mm wastegates on the manifold (exhaust pressure/flow keeping the wastegates open at high rpm).
I think if I used 2 port boost control (push/pull) on the wastegates it would fix that.
On the same note, if I would have had more injector I would have run higher boost.
I am pondering the same idea as op, my twins are shot, and I debated bnr stage 3, but switching to a 7670 would make around the same power, and be rid of all the complex control/problems associated with it....
I currently have a stock port motor, stock fuel system( id plan to upgrade secondarys and fuel pump ), power fc, 3" exhaust, and a thicker stock mount intercooler( thicker core)
pump gas here is usually 92 in WA, I may be a bit paranoid, but I don't feel comfortable running over 14 psi on pump gas.
So id be interested in something that gives good low end drivability and response( like the twins) , and decent power at 14 psi or below.
Hey guys it's me again lol..
I'm finishing up my single turbo build and actually have the same question as ItalynStylion.
So here goes:
EFR7670 0.92 IWG w/ Turbosmart actuators and BOV
Turblown short cast IWG manifold
Custom Vmount
13b-RE LIM and UIM
Freshly built large street ported motor
3.5" inch downpipe with 3" inch full custom exhaust
Crane Hi 6 Ignition
ID1000 and ID2000 injectors
Dual Bosch 044 fuel pump with surge tank
Adaptronic modular ECU
The plan was to get the 8374 but found that amost new 7670 for 1k locally and couldn't pass up.
09-01-16, 09:19 AM
