S4 NA with S5 JDM TII swap (166.3wwhp 157.8wtq)
Thread Starter
Joined: Jul 2008
Posts: 2,515
Likes: 4
From: San Jose, CA (NorCal/S.F. Bay Area)
S4 NA with S5 JDM TII swap (166.3wwhp 157.8wtq)
1987 Rx7 base model NA, with S5 JDM TII swap
Engine related mods:
-KNN Air Filter in stock air box
-3" Racing Beat downpipe -> Racing Beat Test pipe -> OEM NA cat back ->Oldschool Racing Beat RSR dual mufflers
-No AIR pump
-Electric fan
-Blitz BOV
-Cosmo 20b fuel pump (re-wired)
Dyno was a Autodyne 30 AWD Chassis Dyno
Pull was done in 4th gear
Boost crept to about 7.8psi
91 octane gas
Had him let off at ~6500.. I am pretty sure there was 1 or 2 HP to be found had he gone to 7000, but oh well. I was afraid I would hit fuel cut because it was stock ECU.
166.3WHP/157.8WTQ (The owner of the speed shop "calculated" 220HP at the fly due to this dyno's extremely conservative calibrations, and the fact that my car is 2WD)

Here is the video:
For comparison, my friend dyno'd the same day in his S4 TII, and got very similar numbers to mine, slightly less HP, but slightly more TQ. You can find his setup here where he dyno'd a few weeks prior: https://www.rx7club.com/time-slips-dyno-128/s4-t2-pre-cat-cat-oem-exhaust-hks-ignition-amp-91-oct-171-9hp-161-2tqs-978622/ If you are wondering how he lost 30hp from one dyno to this dyno, I would guess it's because the first dyno he went on was a hub dyno and not an AWD wheel dyno like this one.
Anyways, I am very happy with the results, as it is exactly what I expected for just having a downpipe. Since this dyno, I have put in 750 secondaries, and an RTEK 1.7. Now my AFRs hover around low 11s or so in 4th gear at 7k and about 8psi, so I am thinking it is time for a BNR stage 1 or 2 and 10psi. What do you guys think?
Engine related mods:
-KNN Air Filter in stock air box
-3" Racing Beat downpipe -> Racing Beat Test pipe -> OEM NA cat back ->Oldschool Racing Beat RSR dual mufflers
-No AIR pump
-Electric fan
-Blitz BOV
-Cosmo 20b fuel pump (re-wired)
Dyno was a Autodyne 30 AWD Chassis Dyno
Pull was done in 4th gear
Boost crept to about 7.8psi
91 octane gas
Had him let off at ~6500.. I am pretty sure there was 1 or 2 HP to be found had he gone to 7000, but oh well. I was afraid I would hit fuel cut because it was stock ECU.
166.3WHP/157.8WTQ (The owner of the speed shop "calculated" 220HP at the fly due to this dyno's extremely conservative calibrations, and the fact that my car is 2WD)

Here is the video:
For comparison, my friend dyno'd the same day in his S4 TII, and got very similar numbers to mine, slightly less HP, but slightly more TQ. You can find his setup here where he dyno'd a few weeks prior: https://www.rx7club.com/time-slips-dyno-128/s4-t2-pre-cat-cat-oem-exhaust-hks-ignition-amp-91-oct-171-9hp-161-2tqs-978622/ If you are wondering how he lost 30hp from one dyno to this dyno, I would guess it's because the first dyno he went on was a hub dyno and not an AWD wheel dyno like this one.
Anyways, I am very happy with the results, as it is exactly what I expected for just having a downpipe. Since this dyno, I have put in 750 secondaries, and an RTEK 1.7. Now my AFRs hover around low 11s or so in 4th gear at 7k and about 8psi, so I am thinking it is time for a BNR stage 1 or 2 and 10psi. What do you guys think?
Thread Starter
Joined: Jul 2008
Posts: 2,515
Likes: 4
From: San Jose, CA (NorCal/S.F. Bay Area)
I'm pretty sure it revved slow due to that extra drag of an all wheel drive dyno. If you watch carefully you can see that the car is forced to drive both the rear and the front dyno rollers and the transmission between the two rollers.
I believe that dyno reads low because of all the variables added by the extra rollers and transmission.
Hey I didnt know you have an N/A exhaust. You have some power waiting when you switch to a Turbo y pipe. They are very different. There was a racing beat set up for cheap in Modesto I think. I'll try to find it. It was beat up but the y pipe was good.
I believe that dyno reads low because of all the variables added by the extra rollers and transmission.
Hey I didnt know you have an N/A exhaust. You have some power waiting when you switch to a Turbo y pipe. They are very different. There was a racing beat set up for cheap in Modesto I think. I'll try to find it. It was beat up but the y pipe was good.
Thread Starter
Joined: Jul 2008
Posts: 2,515
Likes: 4
From: San Jose, CA (NorCal/S.F. Bay Area)
You are probably right that I am losing power, but honestly I speculate maybe 5hp-10hp at most, so I am not too worried about it right now.. as I have other bugs to squash first lol.
On the bright side my car is super quiet and looks decently stock with the NA cat back
Here is an overlay of an FD with twins, Funkjaw and my car.
The FDs plot has the dip as the twins switch over. Funkjaw starts on the bottom of all three but climbs to second. My plot starts in the middle.
The FDs plot has the dip as the twins switch over. Funkjaw starts on the bottom of all three but climbs to second. My plot starts in the middle.
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Thread Starter
Joined: Jul 2008
Posts: 2,515
Likes: 4
From: San Jose, CA (NorCal/S.F. Bay Area)
So got my Stage 1 on.
188.5 RWHP (and it kept climbing but I told them to stop at 7k)
166.6 RWTQ
AFR 12:1
Setup:
Stock port JDM S5 TII engine
Rtek 1.7
550 Primaries
750 Secondaries
Racing Beat RevII Full Exhaust
BNR Stage 1 @ 8psi
Stock TMIC
Before (Stock turbo @ 8psi)
166.3 RWHP
157.8 RWTQ

After (BNR Stage 1 @ 8psi)
188.5 RWHP
166.6 RWTQ

Here is a vid:

Both dyno runs were done at the same exact dyno. If you are wondering why it is low, because this is an AWD dyno calibrated for "Heartbreak" mode is what the guy told me. I will always go here however because it makes for consistent measuring.
Conclusion: BNR Stage 1, directly bolted on with same PSI as my stock turbo offered a 22hp gain and 9tq gain. Probably the best 600 bucks I have spent in a long time.
Driving wise, the car is more responsive 3000 and up under light load (same response below that), and def pulls harder 5k-7k under wot. I love this turbo!
I have a Microtech on the way, so next dyno will show what this thing can do fully tuned and dyno'd by a professional rotary tuner. Stay tuned! (Pun intended)
188.5 RWHP (and it kept climbing but I told them to stop at 7k)
166.6 RWTQ
AFR 12:1
Setup:
Stock port JDM S5 TII engine
Rtek 1.7
550 Primaries
750 Secondaries
Racing Beat RevII Full Exhaust
BNR Stage 1 @ 8psi
Stock TMIC
Before (Stock turbo @ 8psi)
166.3 RWHP
157.8 RWTQ

After (BNR Stage 1 @ 8psi)
188.5 RWHP
166.6 RWTQ

Here is a vid:
Both dyno runs were done at the same exact dyno. If you are wondering why it is low, because this is an AWD dyno calibrated for "Heartbreak" mode is what the guy told me. I will always go here however because it makes for consistent measuring.
Conclusion: BNR Stage 1, directly bolted on with same PSI as my stock turbo offered a 22hp gain and 9tq gain. Probably the best 600 bucks I have spent in a long time.
Driving wise, the car is more responsive 3000 and up under light load (same response below that), and def pulls harder 5k-7k under wot. I love this turbo!

I have a Microtech on the way, so next dyno will show what this thing can do fully tuned and dyno'd by a professional rotary tuner. Stay tuned! (Pun intended)




