Stock engine, everything?

 

If all else stock that is pretty good. The ignition amp may be adding some power.

 

doubtful. I made 177/170 w/ only a catback in 90+ ambient temps. Solid numbers though.

 

S4, 3 inch downpipe, HKS twin power ignition.

HP increase from 172.9 to 193.5
TQ increase from 161.2 to 183.8

 

Thats a step in the right direction! I wonder if you would make more power on 87 octane? how many pounds of boost?

 

is it 3" in the whole exhaust system?

 

7.8 psi

3 inch down pipe into oem dual exhaust. I'll be testing the Apexi GT spec on the car once I get it enough fuel. I'm too lean now.

 

I only run premium in the car. Unfortunately premium is only 91 octane in the Silicon Valley.

7.8 psi of boost.

 

It was designed to run on 87, hence the question.

Should be interesting to see what numbers you put up w/ a real exhaust.

 

With such a stock car, I'd be interested to see a dyno pull from 1500 or 2000rpm to see the torque curve.

 

Live and learn. I didn't know they were designed for 87. Good to know. I've been sweating 91 for no reason. lol.

I was so excited to have access to a dyno I never noticed that this shop only logs from 3k. I'll ask for a full pull next time.


Also I just found out my exhaust isn't OEM. There was a car with stock exhaust at the meet this last weekend and mine is not stock. I can't find any markings on it so I have no idea what it is. I'll post a pic.

I need more fuel before I can test the intake and exhaust. I found an Rtek 1.7 for sale at the last meet. Should be picking that up. If that falls through I'll put a SAFC neo on and tune it.

 

Right on! The proof is in the putting!

 

Apparently my exhaust is an old HKS system not OEM like I thought it was.
https://www.rx7club.com/showthread.p...6#post11091416

 

If the 1.7 falls through just go for the 2.1. The SAFC is not worth installing.

 

turbo s4's are designed to run on 87 octane ? says who? ive always thought you want to run 91+ octane on anything thats being boosted anything less i thought was bad for the engine, but can be run if you're being cheap, but i thought its not reccomended to boost on it

 

owners manual.

Turbo models, Mazda recommends regular octane for a completely stock Turbo Fc. it doesnt hurt to go to 91, but some people have reported that it actually feel l little sluggish on 91+, If you have 89octane, you can use that

you dont need to run high octane on anything that is boosted. you run what ever the manufacture recommends, anything more is just a waste of money.

 

So friggen true, im tired of telling people this.

That old school hks exhaust is awesome, ive seen a few before that i wish i could get my hands on. Looking forward to seeing more dyno runs.

 

Imo you should be running 91 octane. You have a boosted rotary, don't risk it... especially with your boost creepin' to 7.8 psi and having an ignition amp.

 

Heads up there is conflicting information on our cars. The cars manual says that the cars are designed for 87 as sharigan said but the manual is the same for the N/As and the Turbos. I found this on my fuel door when I fueled this weekend. Turbos need premium. Don't risk your motor over $2 saving per fill up.

 

^ I had the same sticker on my old S5 TII.

 

Yeah some places you cant get 92 and up , i think 91 would be alright.

As far as 87 octane i'd say its probably best to be used in only the non turbo models.

 

Ran 87 in my (s4) turbo 2 for 50,000 miles, half of which were at higher than stock boost levels. If you are on the stock turbo running within the stock turbo efficiency range (12 or less psi) you will be fine on 87 octane.

Running the stock turbo over 12psi is stupid regardless of what fuel you use, and is dangerous on the stock ecu.

 

Runs too hot and innefficiently , though it can still be done its not really a good idea lol.

 

Maybe with AI it might be ok, but if you can afford AI then you could have bought a better turbo, lol.