I'm still trying desperately to figure out why my engine is missing out on the horsepower it is supposed to have. I'm constantly seeing charts of basically stock S4 N/A engines putting down 130+ horsepower and I'm getting tired of it.

Dyno run #1 (dynapack), intake, clogged precats, CS test pipe and catback, wired open ports:
112.1whp @6k RPM, 108.1lb-ft

Dyno run #2 (week later, dynojet), same plus gutted precats:
120.1whp @6.5k RPM, 108.2lb-ft

Question #1: The aux ports on an S4 are open in the "down" position, right? The comparison chart I saw of wired closed vs. wired open aux ports (https://www.rx7club.com/showthread.p...hreadid=300544) had the power curve of the "wired closed" run almost identical to my latest "wired open" dyno run.

Since that last run, I've installed a bonez racepipe, reset the timing (it retared itself a degree or two since who knows when it was last set) and completed the TB mod.

Question #2: Any ideas where the extra 10+ horsepower I should be seeing went?

 

how many miles on that motor? could be leaky seals.
have you ever cleaned your fuel injectors? not with a bottle, I mean had them cleaned.
What is your fuel pressure? is it dropping off?
Check your vaccum and compression. if they aren't right then you have your answer.
do both of your aux actuators acctually open at speed?
is your air conditioner on?

 

To test them, T in a pressure gage and blow into the tube to check at what pressure they open.
Then route the tube inside with the gage on the end, and do a test drive to see when they open.

When they stick, it's usually the shaft & not the internal sleeves.
Just put some penetrating oil where the shaft goes into the LIM.

 

142k, so it is getting tired. Nope, I wasn't going to bother since a 13BT is going in in a month or two. I'll have those 550's cleaned before the engine goes in though.. I have absolutely no idea, but the air/fuel ratio goes stupid rich, it just drops around 5.5k RPM. I know it's not going lean.. The ports are wired open as I mentioned above, that's why I'm asking to make sure "down" is open on the S4. I'm 99% sure it is, just that 1% makes it worth asking.

The A/C is sitting in a box in the shed, so no, it wasn't on.

 

yeah your running too rich on the top end.You can easily get more with a safc.In the s4 the open position is down.