The SLODRIVE '92 SS Build (Now with Dyno Sheet!)

[SLODRIVE]

Well, now that the car's all kinda white, I couldn't ignore the driver's side of the body any longer. Here's an angle of the car I haven't posted yet...I'm sure you'll understand why.


As horrid as the rocker panel looks, everything behind it was still pretty straight, except for the doors and fender :



I took the cordless Sawzall to the junkyard last weekend and hacked off part of another Leggy's rocker, along with a RR wheel arch for later. Once I got back home, I cut the damage off my car and trimmed the new panel to (sorta) match.

Here it is all welded up:

A little Bondo and some Rust-Oleum later, and all looks better. If you can believe it, the total materials cost (INCLUDING the replacement panel and paint) was less than $10.00. It's far from perfect, but hey.


Since I had the welder out and the fender off, I also made up some stronger fender braces in keeping with this car's weirdness.



I'll have a "done" photo up later this week, hopefully along with some decent logs.

[93forestpearl]

Nice job on the rocker. I need to get myself a cordless sawzall.

[asc_up]

Wow, that's frickin' impressive! You, sir, are a gentleman and a scholar....and totally bad-ass

[91legacyawdturbo]

Nice repair! need to do that to my passanger side and the wheel well

[SLODRIVE]

Well...no logs for y'all yet, but I'm working on it, read below.

First, here's the car now after replacing the left doors and the trim on the right doors. At least it looks like a beat-up Legacy instead of a mashed-up clown car. I guess


Hee hee...I look in the driveway now and think "Spy Vs. Spy"!


Now that the car looks better, I took it out yesterday and drove it for over 100 miles. First off, I gotta say I am not happy running with a MBC...I'm constantly fighting part-throttle full boost, and it makes the car buck if I'm not careful around half-throttle. Other than that, this car drives like a sports car compared to the other Leggies here. The suspension and brakes feel great, and the power...I can't believe how fast this thing is with just a TD04. Better yet, it spools up nearly instantly in 3rd gear and up (pretty damn quickly in 1st and 2nd too!), and seems to be holding 14-15 lbs. past 6000 RPMs. I don't doubt this poor old Leggy could outrun a stock (pre-2009) WRX. Nothing wrong with that.

Halfway through the day, I did a little re-tuning. With just the factory ECU, it was running rich on the bottom end and a little lean up top. Pulling fuel with the injector map took care of the low end just fine. I had added fuel up top on the same map, but the A/F under WOT wasn't responding as well to the changes, even as the ECU was learning. So yesterday it occurred to me that my intake setup is TOTALLY different than stock (duh!), and added a few percent on the upper end of the MAF scale. That took care of the air-fuel ratios right away, and today I'm hoping to fine-tune things some more.

Oh, and something else I forgot to mention, and should now: I should be in no danger of maxing out the Hitachi MAF. The F/IC has an adjustable voltage clamp specifically for the MAF, with the default setting at 5v. Although I didn't do any logging yesterday, the A/F never went crazy at 6000+ RPMs, and if it begins to lean out on the very top end when the MAF voltage levels out, I can add more on the fuel map, at least what little more these 440s have. Once it's a little more sorted out, I'll have some datalogs for all. As always, stay tuned!

[Legacy777]

Oh, and something else I forgot to mention, and should now: I should be in no danger of maxing out the Hitachi MAF. The F/IC has an adjustable voltage clamp specifically for the MAF, with the default setting at 5v. Although I didn't do any logging yesterday, the A/F never went crazy at 6000+ RPMs, and if it begins to lean out on the very top end when the MAF voltage levels out, I can add more on the fuel map, at least what little more these 440s have. Once it's a little more sorted out, I'll have some datalogs for all. As always, stay tuned!

Not sure I understand how you can keep the hitachi MAF from maxing out with a voltage clamp.

[SLODRIVE]

Sorry, I kinda misstated my point...clamping the MAF signal won't allow the ECU to realize that the Hitachi MAF is maxed out, thus preventing the injectors from going insane. It's just another 0-5v sensor, so there shouldn't be any reason why it wouldn't work the same way as an FCD. Not to mention that if/when I run the JECS MAF, I'd have to modify the sensor output voltage to fool the ECM anyway, just like with any chip/piggyback.

[vrg3]

Do you have the MBC plumbed right? You want to connect it between the compressor outlet nipple and the wastegate actuator nipple. If you connect it that way you shouldn't get part throttle full boost.

The problem with maxing out the MAF signal is that the ECU doesn't know how much air is entering the engine. Clamping the MAF signal doesn't resolve that problem at all.

[gijonas]

Clamping the MAF signal doesn't resolve that problem at all.

what i was thinking.

[SLODRIVE]

Do you have the MBC plumbed right? You want to connect it between the compressor outlet nipple and the wastegate actuator nipple. If you connect it that way you shouldn't get part throttle full boost.

The problem with maxing out the MAF signal is that the ECU doesn't know how much air is entering the engine. Clamping the MAF signal doesn't resolve that problem at all.

The MBC is indeed plumbed that way, exactly as TurboXS' manual shows as well. I'll admit I got the MBC used with the car and am unsure of its age and condition, although I don't know what would go bad. I'm certainly open for ideas!

I completely understand that the ECU has no idea how much air is entering the motor once the MAF signal is clamped, it simply resolves the problem of the injectors going static open when the ECU senses 5 volts. In a simple sense, the ECU/FIC becomes a MAP-based system instead of a MAF-based system when clamping because the F/IC continues to read off of its own MAP sensor. At that point, I can still control what goes on as far as timing and fuel with the F/IC, which is no biggie in and of itself since the MAF's only clamped at WOT, high RPM. All I can say beyond that for sure is that AEM included a MAF clamp for a reason, and that my A/F is staying stable past the point where my MAF should be maxing out.

Hope that made sense

[93forestpearl]

That is something you'll have to get used to with a MBC. It's like running my Link with a 2D boost control map. Full boost at 1/3 throttle gets old, real quick.

[vrg3]

I guess I see what you're saying. By clamping the MAF voltage you make sure the injectors keep pulsing (instead of just staying open) so the F/IC can still manipulate pulse width. This means that in the range of airflow between when the MAF hits the rail and when the injectors' flow hits the maximum you can get more control over fueling.

Kind of clever. I don't believe that's quite what AEM intended; I think the MAF clamp is meant for cars that have a MAF-based fuel cut.

[SLODRIVE]

I guess I see what you're saying. By clamping the MAF voltage you make sure the injectors keep pulsing (instead of just staying open) so the F/IC can still manipulate pulse width. This means that in the range of airflow between when the MAF hits the rail and when the injectors' flow hits the maximum you can get more control over fueling.

Kind of clever. I don't believe that's quite what AEM intended; I think the MAF clamp is meant for cars that have a MAF-based fuel cut.

Your explanation is far better worded than mine was, thanks! As far as AEM's intentions for a MAF clamp, you may well be right. I dunno

That is something you'll have to get used to with a MBC. It's like running my Link with a 2D boost control map. Full boost at 1/3 throttle gets old, real quick.

That's what I was afraid of. I may try running the stock boost control and solenoid to make it drivable enough to pass emissions, and look for a deal on a standalone EBC. For now, I'll just keep syncing the boost gauge with the gas pedal in traffic like I have been the last two days.

[dropdfocus]

EBCs are the wave of the future my friend... Just a little costly in the initial start though.

[SLODRIVE]

Back with more progress/upgrades...

I swapped the Turbo wheels for WRX 16s with 205/55R16 Winterforce tires, and I think it looks a lot better. Even with the crappy rattle-can paint job, this car's beginning to look a little mean. It's starting to get a few looks from the ricers on Main Street.



I also took some steps to open up the exhaust. Thanks again to Craigslist, we came up with an "Ebay" 3" midpipe and a Perrin 3" axleback with twin tips for a total of $225.

Here's the Perrin after relocating the LR hanger to fit the Legacy, sitting next to the OEM WRX axleback...lol.

...And here it is on the car. The extension I slapped into the front of the mid-pipe is where the cat will go...it should get here tomorrow, and I'll add a couple more hangers then too.



After driving around with this exhaust setup for a while today, I can say two things for sure: The car's noticeably faster, and it's much louder...as in, it sounds a lot like Rob's modded STi. There was also more boost right away, as in it pegged the 15lb. gauge the first time out. I turned the boost down to about 12 from around 14 pounds, and it still feels faster than before the exhaust swap. Again, it's LOUD though...I hope the cat mellows things out a little bit. I kinda doubt it though, haha. No carpet or sound insulation, remember!

I still haven't gotten around to having some logs hosted to post up here, but I at least have a screenshot of a recent log file. The bottom half of the screenshot shows part of a 3rd gear WOT pull. One thing you'll notice is that the RPM's jump around a little on the log, we're thinking it may just be sampling errors in the logging software, and I'm not concerned with that. Also, boost pressure is measured in absolute PSI, so you have to subtract about 12.6 PSI from the pressure readings (column "K") to arrive at what I'm running for boost here at 5000ft. altitude. This is still a tune in progress, but it's getting there.

[dropdfocus]

Well the A/F, injector duty cycle % and MAF voltage all look good through the 5,480 RPM shown in your spreadsheet.

As for the exhaust upgrade, turbos of course LOVE to be unrestricted! If all you ran was a catless DP all day long the turbo would be happy like a pig in mud (and you though I was gonna say sh*t... )

[93forestpearl]

I need to find a decent twin tip muffler, and I'm not willing to pay for a fancy one just to lop the muffler off. I might just end of making one, since I'm so picky.



You log looks pretty decent. A little conservative for the boost you are running, but it definitely works. At that boost I think you could be closer to 12:1, of not there. The size of the TD04 is pretty apparent in how it drops off a little bit as you get above 5xxx RPM.

What kind of gas are you running? If you get a electronic boost controller, you could really take advantage of that turbo and the torque it could provide. Spool it up to 18-20 psi and taper it back down for a serious wad of torque. For instance, a friend of mine was running his '06 WRX on corn with 850cc injectors, and had that TD04 spool to 21 psi, and it was everything it could do to hold 10 psi at redline on that 2.5. Anyways, 350 lb*ft and 250 whp was quite hilarious to see on the dyno sheet.

Oh, and promise me you are getting larger injectors. Like something over 800 cc/min. Since you can control them, go as big as you can. If anything, you can make a nice fuel wall if you overboost.



Keep it up!


Also, lol on the snow tires in July. I still have my Pirelli Winter Carvings on since they are pretty beat. Better than "Warrior" tires, lol.

[SLODRIVE]

I need to find a decent twin tip muffler, and I'm not willing to pay for a fancy one just to lop the muffler off. I might just end of making one, since I'm so picky.



You log looks pretty decent. A little conservative for the boost you are running, but it definitely works. At that boost I think you could be closer to 12:1, of not there. The size of the TD04 is pretty apparent in how it drops off a little bit as you get above 5xxx RPM.

What kind of gas are you running? If you get a electronic boost controller, you could really take advantage of that turbo and the torque it could provide. Spool it up to 18-20 psi and taper it back down for a serious wad of torque. For instance, a friend of mine was running his '06 WRX on corn with 850cc injectors, and had that TD04 spool to 21 psi, and it was everything it could do to hold 10 psi at redline on that 2.5. Anyways, 350 lb*ft and 250 whp was quite hilarious to see on the dyno sheet.

Oh, and promise me you are getting larger injectors. Like something over 800 cc/min. Since you can control them, go as big as you can. If anything, you can make a nice fuel wall if you overboost.



Keep it up!


Also, lol on the snow tires in July. I still have my Pirelli Winter Carvings on since they are pretty beat. Better than "Warrior" tires, lol.

Thanks! I know the tune's still a bit rich a WOT, but I'm working on it. Right now, safety is priority one while I'm still fiddling with the F/IC. I do have larger injectors sitting here for when I feel I need them...they're not 800s, though, just STi 550s. As for fuel, the best we get here is 91 octane, although at this altitude it's roughly equivalent to 93 octane at sea level. Any suggestions for resonably-priced boost controllers? I've been eyeing used JDM Greddy and HKS units on Ebay.

Oh yeah, I made more progress today too. I got my cat in the mail, along with a 25# VDO boost gauge and a "proper" (Longacre) tire pressure gauge. I love the USPS!

The cat went right where I had the sleeve, and voila...catted 3" midpipe! Isn't that little converter cute? It's stainless, OBD-II certified, and cost all of $50. Believe it or not, that little sucker is rated for vehicles up to 5.9 liters. Heh.

I also ordered some exhaust wrap on the 'Bay along with some stainless zip-ties. It's amazing how cheap this stuff is online...I got 100 feet of 2" wrap for $40 shipped.
Here's the downpipe all nice and wrapped up, to help keep the convertor hot. Sure is purty.


...And all installed. The whole system is super rigid, and has just enough room that it shouldn't bump on anything...that I'll make sure of tomorrow on the road, and maybe at CORE.

[93forestpearl]

I want to get a metal substrate cat for mine too. It's on the list, but down a bit. I need $400 worth of clearcoat before anything else.




If I were you, I'd get a Turbo XS knock light. They are pretty reasonable ($120), and will give you a heads up if you hit the limit fuel-wise.




As far as electronic boost controllers, I have no idea. I've been using my Link Plus G2 for boost control since day one, which was over 2.5 years ago. Anything you can make a 3D map with or closed loop per RPM will work for you.

[93forestpearl]

Also, I need a bunch of wrap. Got an ebay link to moar??

[SLODRIVE]

Also, I need a bunch of wrap. Got an ebay link to moar??

Yep...the seller has some very reasonable combos, like THIS.

The convertors are all over Ebay, whenever you want one there'll be plenty available for $50 or less shipped. I've been looking at the Knocklite, I think I'll pick one up one of these days, & I'll keep researching boost controllers, thanks for the advice though. It's emissions time this week, so we'll see if the stock boost control works...it wasn't hooked up when we got the car.

[SLODRIVE]

Couple of updates...

Got the new boost gauge in, it's MUCH brighter than the old one. I also found my old shift light from a monster tach that got ripped off years ago and hooked it up to the 12V output of the F/IC. It works great...almost blinding!


Right after that, I hooked up the factory EBC, re-set the ECU, went for a little drive...and then stopped by the emissions place with fingers crossed.

Passed with flying colors, almost to my surprise.


Driving around the factory boost control was...interesting. Due to my mods and altitude, it still made nearly 11 pounds of boost. Spoolup was quite a bit slower though, to the point where it was actually less fun to drive than the MBC, which I re-connected as soon as I got home. Huh, I was actually expecting less boost and better spool-up. Shows what I know!

[93forestpearl]

Nice. I could pass emissions, especially if I installed a cat, but the visual inspection wouldn't go so well. lol

[dropdfocus]

Cats installed on a car?? Really, you have to do that sorta thing? (yes I'm joking)

PA requires them for visual through out the entire state, but only a handful of cities require the tailpipe sniffer test to pass. So I miss out on the chopping block for that one & the shop I go to lets me slide by simply bringing the stock WRX catted D/P with me to pass the visual. Since it can be swapped out in the matter of 1hr, he figures I could have changed it for the inspection.

[91legacyawdturbo]

Cats installed on a car?? Really, you have to do that sorta thing? (yes I'm joking)

PA requires them for visual through out the entire state, but only a handful of cities require the tailpipe sniffer test to pass. So I miss out on the chopping block for that one & the shop I go to lets me slide by simply bringing the stock WRX catted D/P with me to pass the visual. Since it can be swapped out in the matter of 1hr, he figures I could have changed it for the inspection.

Its pretty easy to swap out the whole system, I have to do it every two years at 30 bucks.