Might be a stretch, but would you be willing to post the tuning map for your supercharger setup?

 

Oh wow, this was posted a year ago....

I would share it with you, however, I lost the data on the laptop I was tuning with. I haven't touched my tune in awhile now and it does have its issues. The tune is far from what you need as a result of the different setups, but I'm also considering going to a 257 block which will bring us closer together.

 

Yes! That would make me very happy...my tune is pretty rough. I have it running so stupid rich that I'm backfiring constantly when engine braking. :lol:

 

Finally got around to installing a second throttle body to control the volume of air the SC is exposed to at idle.....now my 45 degree elbow in my fender is collapsing. I plan to put in a 90 degree elbow(the actual angle of the bend) or get a 90 aluminum elbow and cut it to size.

my only other option is to keep the throttle body in front of the supercharger partially open, but I'll wait to see if stopping the collapsed elbow in the fender resolves issue.

 

What opens the pre-SC throttle body fully, if I'm right in thinking your driver-controlled TB is the one on the intake?

 

I cut and spliced the wires since I'm DBW. It was relatively easy to setup this way rather than dealing with routing a cable to control both. I may end up drilling a few small holes into the throttle body controlling the SC so that the vacuum between the two TBs is reduced. That will be the last thing I try though; if I can keep the coupler(s) from collapsing I "shouldn't" have any issues.

 

Wait, you have TWO fully active throttles? Why not just run the pre-SC one alone, since at this point the BOV shouldn't be doing aything? And I'm surprised the ECU doesn't complain about the higher draw on the driving circuits.

 

Yeah, I'm running two separate throttle bodies now to keep throttle response stockish.

It's a pretty common mod over on the Miata forums.

 

That seems like adding unnecessary complication, but as they say "If it's stupid and works, it isn't stupid."

 

I want it to drive like stock (stock idle and feel stock both in/out of boost) but I also want it to be moderately quiet unlike the blow through setup. I'm certain that having two throttle bodies is the only sensible way to achieve this.

 

I mean, I only have one throttle body... Okay, I have idle issues, but that's a tuning problem.

 

I notice with only using the pre-SC throttle body there is noticeable throttle delay likely related to all the extra piping in my build from running a FMIC. I'm not really interested in redesigning again just to use a TMIC to reduce the throttle delay that I'm experiencing. With that said, when only the Post-SC throttle body is functioning the throttle response is there without hesitation but it's super loud because full boost at idle. With both throttle bodies running I seem to be getting the qualities I'm looking for; just waiting to resolve the collapsing silicon coupler issue.

 

Hmm, that doesn't make sense, assuming it was tuned for it. Is it a visible difference in the log, like you can see a delay between the throttle opening and the boost? I guess in theory it could remove a teeny bit if the piping is already flooded with air.

Definitely keeps the intercooler cooler.

 

The delay is when it's out of boost; when it's in boost it's not noticeable. It's caused by the distance the air has to move past the throttle body before reaching the motor that's causing the delay (only out of boost when supercharger is turned off) Also I'm drive by wire rather than cable, so there is already a noticeable delay in response when compared to a cable design.

 

Oh, I forgot you had a clutch on the supercharger still.

Did you not retune the DBW? I know a lot of WRX owners had success with making it feel more like a traditional cable throttle.

 

I did; that was the first thing I changed in the ECU

 

Huh! It seems weird to me considering forester06x effectively has the same engine with a FMIC but doesn't report similar lag.

 

It's not lag but a slight "hesitation" on throttle out of boost. It's not as bad as you must think it is. I could tell that it was there, and now it's not .

 

Alright, I've finished the build and I've got it running like a champ though I need to make a few minor adjustments in the tune. My car has never driven so smooth and the transitions in and out of boost are amazing.

Yeah, it looks weird but it works. I needed a valve that I could use to fine tune the amount of air the supercharger was getting. With the motors higher efficiency over the supercharger, I was getting insane amounts of vacuum between the 2 throttle bodies. Allowing the supercharger to get a little more air resolved the issue. I originally planned to drill a hole in the first throttle body but guessing the size of the hole I needed just seemed like a bad idea.

 

"If it's stupid and it works, it's not stupid."

 

I've spent some time tuning the subaru; was actually working on MAF scaling in this pull but regardless; the data was fairly decent; sorry I forgot to log boost :S. I'm actually pretty impressed even though I am running NA 2000 grind cams. I happen to live right next to a long 1-mile bridge that crosses over a lake that makes for the perfect road dyno. I started getting belt slip around 5000 rpms.

 

Yeah, the tuning for these SCs really seems like the hardest part.

(Well in my case it's the headgaskets too, but you know.)

 

So I made a thing. See attachment.

I had modified and added on the the original one so much that it became an issue with fitment. Finally broke down and made a new supercharger inlet and on the plus side it looks way better than the original.

 

I WANT ONE!! Nice work... I've long wanted to fix the sharp corners of my box-shaped intake... Gotta get off my butt and do that!

 

It wasn't too hard to make. Alumalloy rods and a MAP torch to weld it up worked pretty good. The welds aren't beautiful but without a TIG welder you really can't expect pretty welds. The only tools I used were a drill press and a metal chop saw; everything else was done by hand which is probably why I've had a back ache for the last week or so (lots of filing). My original one was steel and had a pretty harsh right bend with a corner in it.

 

New video of Supercharger running

 

redid a few things...think I'm about done changing it up.

 

Dude, that looks great! Love the gold.

What's that protuberance off your charge pipe right by the AC compressor?