twins non seq (everything done except removal of the exhaust flapper, that is held open)
​​​stock port rebuilt 12k miles ago
Twin blitz intake
Dump Valve HKS SSQV
FMIC blitz style 18x11x2.75" core
Catback 3.5" titanium
Midpipe 3" inox unsilenced
Downpipe 3" trust
ECU Katayama Racing (ajustment fuel/ign/fuelcut/lubrification/speed cut...)
Peter Farrell Supercars PMC purple (ignition, fuel, limiters...)
Modded primary rail
850cc primaries
1300cc secondaries
Z32 fuel filter in engine bay
MBC Hallman Pro RX
Walbro 255High Pressure hardwired
NGK BUR9EQx4
NGK wires
Ground kit HKS
Koyorad type-R

14.5PSI
340WHP
375BHP
445N.m / 45m.kg

I'm pretty happy with the results. I think I need an ignition amplifier to clean the upper RPM curve. What do you think of the RWHP => BHP convertion value?


https://cimg9.ibsrv.net/gimg/www.rx7...d088ac037e.jpg

https://image.noelshack.com/fichiers...0903143103.jpg

 

 

I have a wideband on board. 11.4 at 5000 and goes gently to 11.1 at 8000. EGT below 890°C

 

http://image.noelshack.com/fichiers/...2-img-7139.jpg

 

Great number but how long are those twins going to last?

 

@ 14psi / 340rwhp I think the twins last fairly long- just the exhaust sides slowly cracking apart as usual.
That is the pretty standard "boost up" in Japan since it is near the limit of the stock injectors. And, its hard to call anything less a "boost-up" when they run 12psi stock in Japan for the high power spec...

In this case of parallel twins its even easier on the primary turbo since its not getting maxed out before transition like on a sequential set-up that brings the flow up but doesn't lower the switch-over point.

If I were to start pushing the stock twins 17psi+ and over 380rwhp I would want a spare set of twins or an upgrade path ready.
Could last several years/seasons of drag racing (like tom94RX-7 who eventually got up to 411rwhp @21psi and 10.87et on stock twins) or about one track event. So depends on what type of racing you are into.

 

How nicely does the ROM tuned ECU run with the 850cc primaries and the 1300cc secondaries?
Still super smooth transition on 2ndary injectors?

I had my ROM tuned ECU done by Knightsports to max the stock injectors, but it would be nice to have an inexpensive upgrade path available.

 

I chose 1300cc in order to keep factory smooth transition, and it worked great. The rom tuned ecu is mapped for stock injectors and I use it as a boost fuel cut, and speed cut remover mainly. It also increases omp flow on high loads and fan management. The injector rescaling is done with the pfs. The fine fueling and timing adjustments are Also done with the pfs. Both work well together. It's a bit oldschool but it does the job.

I'm happy with the result and dont plan to increase boost. I just want to clean the upper curve with the help of some ignition amplifier maybe. I particulary appreciate the 4000rpm torque peak. It's a good surprise on a parallel configuration.

 

Nice numbers!

 

Thanks! I love that car!

 

What would cause the glowing exhaust with flames?
Is it too rich? EGT too high? Timing?

I run the same configuration and my exhaust don't look like an afterburner.