Ok so i have an S5 Vert with a Turbo swap. im still using the NA tach which has a higher redline than what the turbo tach. should i stay with the 7K redline or is it safe to hit 8K

 

S5 TII redline is 7k, not 8k like the S5 NA. Your stock turbo will choke past 7k anyhow.

 

your the best rotaryrocket.. thanks again as always

 

my turboII see's 7k about 10x a day lol 8k on occasion when the tires lose traction lol

 

Just gonna ask if you really thought that because the tach changed the engine condition would have changed to allow it to hit 8k? (not being a dick, more of a smartass)

As posted by RotaryRocket88 the redline stays the same for the engine. You'll probably be able to rev it to 8k, but there's less power than at 7k. So until you replace the turbo with something that can breathe at that rpm, 7 is your magic number!

 

HAHA.. im not that much of an idiot. i was just wondering if since the S5 tII still had the lighter rotors if 8k would be safe for it since the lighter rotors on the NA is the reason you get a 1k Rpm increase. but now i know stick with 7k. or less untill i get my waste gate ported.

 

you could take it to 9k if you wanted and the ECU allowed it to. mazda just chose to lower the redline to keep the possibility of engine warranties lower.

 

I have the rev limit set to 8500 on my s4 T2 in part because for 1st and 2nd gear it's hard to keep it off the rev limiter. In 3rd and 4th I take it up to around 7500 usually. I haven't dyno'd this engine yet but the last one had a powerband that flattened at 7000 and fell off at about 7500.

stock ports and stock/hybrid turbo is out of breath by 6500 usually and there's no point in shifting after 7000

While continual redlining certainly doesn't help longevity, the cool thing about a rotary as it won't fly to pieces from high revving. you don't have head lift, valve spring problems, etc. The engine will just stop making power. So even if you can take it over 8000rpm turbo engines almost never make power that high without a big turbo and aggressive porting.

 

that's true, and mainly why they put the redline where it is but the engine can go higher safely.

 

The thing I wondered is the with the S5 Tii they listed the redline as 7k and the n/a as 8k given the same rotor weight, but the flywheels are lighter. The FD with the same rotor weights and turbo have a 8k redline with a sustained of 7.5 of under, the only real difference I see is the FD vs s5 tii has a slightly lighter flywheel. The only thought that popped in my head was that they were worried about high rpm vibration with the heavy flywheels.

 

turbos have an island of efficency, if it cant move enough air, its doing more harm than good..