Copyninja Street FD - GT3 Build

Boy you a new mapper on the block huh 🤣🤣
I guess you could say that :ROFLMAO: new levels of intimacy in my rx7 ownership.

Mapped it to 1.2bar on the road which was extremely lively, some poo my pant moments as the car wanted to step out in 4th 🤪. Next is to book a dyno and to gather evidence and see where the turbo starts run out of efficiency as I get closer 1.4bar.
 
Another wonderful dry and sunny day today so I decided to go out and up the boost instead of wait for a dyno day and see where the upper limit would be before my fueling ran out.

I got the high boost up to 18.7 psi approx 1.3ish bar and I'm now running out of injectors. I may up the base fuel pressure to 55psi to see if I can gain more fuel deliverability but I doubt it will make a significant difference. Got a little bit of cleaning up to do with the fueling but pretty much on the money.

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Another dry day today so I increased the base fuel pressure to 60psi and fully remapped the car for a second time and I can confirm I have gained approx 7.4% additional fuel delivery and have enough fuel for 1.4 bar of boost which is amazing considering I'm on 550cc primaries and asnu 1500cc secondaries. If you are running bigger injectors and still running out of fuel chances are your mapper has probably been lazy.

When my car was initially mapped by a more experienced mapper at only 1bar; I was told I needed bigger primaries if i wanted to run above 1bar of boost as my injector duty cycle was running at 90%. I dont know if this was a knowledge gap or lack of experience setting up and optimizing the fuel staging and injectors or deliberate to make some monies....but anyways I'm glad I sorted it out myself.

New base fuel pressure of 60psi running 18psi at a pig rich 10.20 afr and my duty cycle is sub 90%. That's some result without changing the primary injectors.
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Cleaned up the fueling a bit more and injector duty cycle is now within 85% which I'm very happy with. My actual fueling is approx 2% richer than my target but I've chose to run it this way to keep egts under control.
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Running approx 18.6 psi tapering down to 18 psi at redline and feels incredible even though my afrs are approx 2% richer the car feels incredibly responsive and fast.

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I have booked a dyno for a couple hrs mid march where I can play around with the boost a bit more and see if there is any real power difference between 1.3 to 1.4bar. Also get some power figures and do some dragy gps runs.
 
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For the time being I'm very happy with the high and low boost maps and everything in between....so wont be making any more tweaks with the maps until 12th March. Be interesting to see if I can get close to my 450rwhp goals and see what kinda power it actually puts down.

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In the interim, the left headlight cover has been a victim of all the power pulls Ive done road mapping and dialling the car in.

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Ordered a replacement set of concept 7 covers which I've already dropped off to my local body shop...so I should have the new one's fitted before the weekend. I've been told the side fitment is not the best....but looks oem fitment on closed position.

Next thing to do is to fully overhaul the underside and interior. I've been putting this off for year's due to the rotary unreliability of my 2nd rebuilt engine. However, thats in the past now and Tim has built me an amazing motor and restored my faith in rotary power! 😁
 
Loving all the tuning updates, I've been learning tuning too (online, not put to the test just yet).
I'm nearby in Bridgend too, will have to compare notes at some point after lockdown!
 
Loving all the tuning updates, I've been learning tuning too (online, not put to the test just yet).
I'm nearby in Bridgend too, will have to compare notes at some point after lockdown!
Honestly the best thing I've invested my time in during this covid downtime.

Bridgend is fairly local dude, who are you learning with? Sure thing more than happy to provide you with some tips.

Which ecu and setup are you planning to run?
 
Are you measuring EGTs ?
I haven't got EGT's connected directly to my link ecu as I don't have enough free channels which includes my expansion loom. Do you have egts on yours?

However, I used my good friends plug and play egt probes for both rotors with ugly af analouge gauges in car while tuning. Thus the afrs I've chosen for my application. To some they may seem a tad rich and there is no doubt they are but they give me a safety net which allows me to run multiple WOT pulls back to back and simulate dragy gps runs from 2nd-5th much like you would on a trackday and both rotors are hovering between 890-980*C. There is no doubt I'm trading some power for the additional cooling.
 
I haven't got EGT's connected directly to my link ecu as I don't have enough free channels which includes my expansion loom. Do you have egts on yours?

However, I used my good friends plug and play egt probes for both rotors with ugly af analouge gauges in car while tuning. Thus the afrs I've chosen for my application. To some they may seem a tad rich and there is no doubt they are but they give me a safety net which allows me to run multiple WOT pulls back to back and simulate dragy gps runs from 2nd-5th much like you would on a trackday and both rotors are hovering between 890-980*C. There is no doubt I'm trading some power for the additional cooling.
Yes I have 2 x EGTs, one on each runner

I used a KMS EGT box via CAN
 
Honestly the best thing I've invested my time in during this covid downtime.

Bridgend is fairly local dude, who are you learning with? Sure thing more than happy to provide you with some tips.

Which ecu and setup are you planning to run?

Yeah I'm really enjoying so far. I've got evans performance academy, its got generic tuning tips, then courses on specific ecu's (haltech + link), also some live tuning series (he's got one on a single turbo rx7 with a haltech elite)
Also got the hp academy wiring fundamentals course which was good too

At the min I'm on twins, with a haltech pnp kit (elite 2500) not used it yet (currently on a rich JDM chipped stock ecu )
Need to get some driving in and re-compression test it (as its low)
So setup will either be twins+old engine, or rebuilt engine + efr8374 or 362sx-e (8376 equiv)
 
Yeah I'm really enjoying so far. I've got evans performance academy, its got generic tuning tips, then courses on specific ecu's (haltech + link), also some live tuning series (he's got one on a single turbo rx7 with a haltech elite)
Also got the hp academy wiring fundamentals course which was good too

At the min I'm on twins, with a haltech pnp kit (elite 2500) not used it yet (currently on a rich JDM chipped stock ecu )
Need to get some driving in and re-compression test it (as its low)
So setup will either be twins+old engine, or rebuilt engine + efr8374 or 362sx-e (8376 equiv)
Sounds good, EPA know what they are doing, I learnt my open loop boost control strategy from them. Running it closed loop is a bit more complex and you have to be mindful if tuning on a hot day for big boost applications as the same car on a colder day is asking for trouble specially if the mapper doesn't account for this.

Single for the win if the old engine is good, run some premix and around 0.8 - 1bar boost if you want to be safe and conservative. If you have water injection; you can go higher. The 362 sxe is a great choice.
 
The weather must be improving as it was another dry and cool day.

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So instead of waiting for the dyno day, I took my trusty laptop and upped the boost to 20.7 psi; approx 1.42bar. The car feels incredibly quick and mega responsive from 3.5k to redline; butt dyno suggests zero lag as it just picks up and goes.

Will clean up the fueling a bit more but it's pretty much sitting on the money.

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I can only imagine how good the newer EFR turbos must feel on transient boost response where I can see mine takes time to build max boost again after a 3rd to 4th gear shift while in the boost window. I suspect this is where the EFR turbos must shine?

Were it not for this logging data; the butt dyno would suggest there is no lag and that's how it will feel for the vast majority behind the wheel.

Below is an example of an earlier log I did while dialing in the boost.
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On these logs it's evident 3rd gear shift from WOT into 4th and although in the boost window the turbo does not make max boost instantly...it's building back up to max boost. I suspect this trend will be much worse on older, bigger and non efr turbos.
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EFR and SXE owners - I'd love to see some data on this please? does your EFR instantly spool to max boost once 100% throttle is applied post gearshift?!?
 
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Interested in this as well, the bearings on the efr are meant to be very effective allowing it to spool so quickly. If I end up getting a efr/sx-e I'll have to grab a turbo shaft speed sensor, as it'll be really interesting to see what it gets up to. Should be an interesting parameter to account for in the tune too.
 
Interested in this as well, the bearings on the efr are meant to be very effective allowing it to spool so quickly. If I end up getting a efr/sx-e I'll have to grab a turbo shaft speed sensor, as it'll be really interesting to see what it gets up to. Should be an interesting parameter to account for in the tune too.

Yup would be great to see some data on the EFR/SXE line regarding their transient boost response.

That would be an interesting parameter to monitor.
 
I was doing some cold start tuning and found my battery voltage is dropping down to 7v on a stone cold start..which doesn't seem right as I've got 12v before crank.

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Did another test the next day, just incase my odyssey pc680 was on the way out? I hooked up my daily driver to the rx7's battery via jump leads and right away the cranking was much stronger but still seems like I may have a starter/wiring/voltage drop issue. It was showing 14.48V before cranking which suggests the ecu is seeing the correct battery voltage, but it is still dropping to 8.2V during cranking. There is also a spike in TP and a few other analog channels right when I start cranking which may suggest the issue is a bad ground?

Also something odd is going on with fuel pressure, it varies a lot with battery voltage so that also suggests fuel pump is seeing the same voltage issue. I have only 47 psi differential press during cranking vs 61 psi when idling..which is again a bit strange.

Has anyone had this issue? and do you guys think its the PC680 on the way out or the Starter/starter wiring/grounding? any thoughts or trouble shooting appreciated.

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Also found the limit of my fueling at 1.4 bar of boost as the data confirm I was running out of injectors as duty cycle was touching 92-93% which I wasn't comfortable with so just to buy a little bit more headroom and gain a bigger safety margin I got a set of 850cc reconditioned injectors from here and a new Walbro F90000274 fuel pump as my Bosch 044 is struggling to keep up with the fuel delivery All in all a fairly cost effective upgrade to gain a bigger safety margin.
 
Seems like a poor battery and some grounding issues maybe? Battery should be sat around 12.7V ish prior to cranking if healthy and not much load on it. Dropping to 7V during cranking seems very extreme.
Another test would be to pull the rx7 battery and just use the dailies and do a log. Daily battery may be struggling to start the car and have your rx7 battery trying to drain it.
Voltage drop at the fuel pump is common, have you done the direct feed + relay mod? If you haven't try and get a multimeter across the fuel pump terminals and see what voltage you get.
With the stronger fuel pump voltage, you may find you have a bit more headroom on fuelling.
 
Seems like a poor battery and some grounding issues maybe? Battery should be sat around 12.7V ish prior to cranking if healthy and not much load on it. Dropping to 7V during cranking seems very extreme.
Another test would be to pull the rx7 battery and just use the dailies and do a log. Daily battery may be struggling to start the car and have your rx7 battery trying to drain it.
Voltage drop at the fuel pump is common, have you done the direct feed + relay mod? If you haven't try and get a multimeter across the fuel pump terminals and see what voltage you get.
With the stronger fuel pump voltage, you may find you have a bit more headroom on fuelling.

Agreed, def something not quite right there. Either my PC680 race battery is going bad, even though its on trickle charge or some poor grounds which need investigating.

Ahh yh thats a great idea, I'll use my daily driver battery and see what the log says.

Yh my fuel pump is hard wired to the battery...and the fuel pump and the ecu are registering the same voltage drops, leading me back to bad ground or bad battery?