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HKS TO4Z Large Street port build 390 BHP and 316 lb FT with Dragy GPS data
Engine - Large street port, studded and balanced with RA super seals - 8000 rpm max rev limit. Turbo - Garrett TO4Z 1.00 AR Power - 390 bhp at flywheel Boost - 0.7 bar of boost WMI - No Torque - 316 lb ft at flywheel Weather conditions - Wet Gearbox - Oem 5 speed manual Final drive - 4.44 Wheels and Tyres - Advan RG2 17 x 9 All round. Michelin Pilot Sport 4 with 245 40 17s all around.
Only mapped on low boost at 0.7 bar running 390 bhp and 316 lb ft at the flywheel.
In a few weeks with water injection it will be mapped to 1.2 bar and hopefully make close to 500 bhp so I will re-run the Dragy GPS acceleration runs again.
I managed to do some Dragy GPS runs in wet conditions shifting up before 7000 rpm, It was wet and quite sketchy when i did the below runs so please excuse the granny shifts. There is still a bit of room here for improvement in dry conditions with warmer tyres and revving out to 8000rpm and shifting from 4th - 5th a bit quicker.
60-100mph in 4.46s (Shift from 3rd to 4th)
60-130mph in 10.55s but also gives an accurate breakdown of other metrics below like 60-90mph and 60-120mph.
Can be much better, it was wet and i hesitated shifting from 4th to 5th and going uphill doesn't help either.
Finally the very popular 100-200 kph in 9.29s (62-124mph but i have 63-125 mph which is close enough).
There is definitely room for improvement here, in dry conditions with warm tyres without an incline and revving out to 8000rpm should see this come into the high 8s range.
Once my car is remapped at 1.2 bar I will run the above acceleration runs again.
Does anyone have valid/verified dragy gps runs on their 500/600/700 bhp rx7s? Will be good to see how much faster a 500bhp or 600bhp rx7 accelerates.
Draggy or Vbox is good enough as long as its verified/valid.
Notice that one is running 27psi and C16 race fuel so not completely representative for the vast majority. However, impressive 60-130mph of 5.92s if that data is indeed valid!
Will try another run in the dry soon. Hopefully get into high 8s or mid 8s with no incline. In a few weeks i'll turn the boost up to 1.2 bar so will have some more data.
Surprisingly ran out of injectors at 1 bar as inj duty hit 85%. I am running 550cc primaries and 1500cc secondaries with a Bosch 044. Does anyone know if I should be hitting 85% DC on this fueling setup. Base fuel pressure is 50psi.
Raising boost to 1.4 bar still eludes me. However, still happy with the performance at 1bar....picked up approx 60rwhp going from 0.7bar to 1bar...so a fairly decent result going up 0.3 bar. Following that trend going up another 0.3 bar to 1.3 to 1.4 bar should get me closer to the 450rwhp goal.
The weathers been real bad so have not had the chance to do any Dragy GPS runs. Will do as soon as the weather permits.
Got More data as i had the car mapped on a rolling road.
12psi made approx 350rwhp.
20psi made approx 400rwhp
Dyno Dynamics rolling road dyno. This dyno had issues and could not match tach as the car was being revved out to 8krpm...but this dyno only shows 6.5-7k. Did a power run on another dyno jet rolling road to gather some data....Almost similar results....different days similar..ish results. High boost run.....but I've got some issues thus the top end looks a bit lame.
As we don't race our cars on dyno's; I also went out and gathered some data on how the car performed in the real world and to verify if there was a difference between a 350rwhp and 400rwhp RX7. The results were interesting.
I chose the 60-100mph performance indicator to test the acceleration on the street as this is where most of the street battles and rolling pulls would be done. The consideration here was in stock rx7 transmissions this is a simple 3rd and 4th gear WOT pull.
In summary, 350rwhp does 60-100mph in 4.85s
370rwhp 60-100mph in 4.46s (the above dragy gps data was for 1.2bar or 370rwhp)
400rwhp does 60-100mph in 4.02s.
