Boosting the Mirage

[twistedwankel]

I just want "some" power, and to be sure my AFR's aren't too lean.

I think Loren is afraid the Mirage won't be able to spin the drum and it will stall. It probably won't measure that low. I've never seen anyone run a bike on a dyno. Maybe they have one at HD for a trike?

[jbrannon7]

Chassis Dyno: $80 will get you three runs at WOT with AFR's. Do a baseline and then do it again after your mods. This will confirm the HP increase and verify the motor won't blow up on the autocross course. Seems like solid investment. Others on this board might support this.

I'll tell you what. I called 4 or 5 shops in Pinellas County that had dynos when I had my BMW and NONE of them would let me on their dyno for less than $400.00 dyno tune fees.

[JasonS]

Hey, I might he in M2 also for the 2020 season since evos are now DS class.

Still can't believe the new classing. Putting an evo in the same class as a wrx is plain ol' not cool.

Can't wait to hear the mirage whine...

[twistedwankel]

Chassis Dyno: $80 will get you three runs at WOT with AFR's. Do a baseline and then do it again after your mods. This will confirm the HP increase and verify the motor won't blow up on the autocross course. Seems like solid investment. Others on this board might support this.

I'll tell you what. I called 4 or 5 shops in Pinellas County that had dynos when I had my BMW and NONE of them would let me on their dyno for less than $400.00 dyno tune fees.

I went thru the whole ugly story and wrote down Ramsey's Performance - Chassis Dyno 813-909-2600 off the bldg photo where Tim took his cars. Worth a call.

[Tim_M]

Chassis Dyno: $80 will get you three runs at WOT with AFR's. Do a baseline and then do it again after your mods. This will confirm the HP increase and verify the motor won't blow up on the autocross course. Seems like solid investment. Others on this board might support this.

I'll tell you what. I called 4 or 5 shops in Pinellas County that had dynos when I had my BMW and NONE of them would let me on their dyno for less than $400.00 dyno tune fees.

Joe: Surprising how many shops are in the area - Omaha we had 'one.' Fortunately, Tampa has more. Coastal in Brandon area does it for $135 for the first hour, Vortex on Waters does it for $100 an hour, and I settled upon Ramsey's at $80 for 3-4 runs (typically an hour). None of those include them tuning your car although you can tune it yourself and then execute a run, etc - price is based on time. I've used all three in the last 11 years.

Ramsey's is a Dynojet (WOT only). Vortex and Coastal are full eddie current (Mustang) models for WOT and any part throttle. Full tunes are substantially more and depend on the tuning tool required - HP Tuners.

Nonetheless, a naturally aspirated engine is hard to destroy when you do something wrong. A turbo, nitrous, supercharged engine will destroy itself much more readily at WOT with the wrong keystroke. Automatic to dial in the WOT on a dyno and then play/extrapolate the part throttle on the street (nil chance of destruction).

Nonetheless, apologies this thread wasn't about about dynos...more about Loren doing it the hard way. Will be entertaining! Certainly unique project no one else has done.

[Loren]

Hyundai Elantra Sport - This car is the winner. The only two things I don't like about it are that it's fairly long by my standards (18" longer than the Mirage), and fairly heavy by my standards (3100 pounds). It has everything the Veloster has, PLUS a much more refined independent rear suspension rather than the ox cart beam axle that's on every other FWD car. I've spent some time in a rental Elantra SE and really liked it. Add power, better suspension and tires and a manual trans? Hell, yeah! Sleeper autocross car.

Adendum - I just saw an "Elantra GT" on the street. GT is the name they give to the hatchback version of the Elantra. Apparently, the "Sport" version of the "GT" didn't happen until 2018... but, it's a thing. And it's 9" shorter in length than the sedan! They're speaking my language.

[aw614]

If it is on the same platform as the Veloster (I think it is), apparently it is easy to get -3 degrees of camber up front per the grassroots motorsports reviews/videos on it through the crash bolts.

[Loren]

Nonetheless, apologies this thread wasn't about about dynos...more about Loren doing it the hard way. Will be entertaining! Certainly unique project no one else has done.

Okay, I'm gonna bite. Why not?

I've given an overview of the project, and a rough budget. Let's talk about the PROCESS, and how it might differ if I opted to go pay for dyno time. You're making it sound like I'm making some huge mistake by not going to the dyno. I just want to be sure I'm not missing something.

Goal: Boost the car by 3 psi and be sure that the WOT AFR never exceeds about 12.8:1. Is that ideal? Nah. Is it safe enough for 3 psi of boost? It's a risk I'm willing to take. That's the goal. 3 PSI of boost... maybe 12-15% increase in power. Keep the AFR in a range that *I* think is safe enough.

Process:

A. Spend $80-200 or more to get a baseline dyno run. Stock engine on the dyno should be right at 60 hp. With my light mods, maybe I'd see 63-66. I'm not wasting my time or money to verify that. It is what it is.
1. Install AFR gauge to monitor fuel status. The car has an OE wideband O2, I *may* be able to read that through OBD. If not, I'll install a wideband and a gauge.
2. Do some baseline street testing to see what the AFR's are now. I can do this with 2nd gear pulls just about anywhere. 2nd gear only goes to 55 mph. If the baseline AFR's are too lean (it IS an uber-economy car), I may have to either abandon the project, or go ahead and plan for some fuel control.
3. Install a boost gauge to monitor the boost level.
4. Install the supercharger with a restrictor plate to 75%. I figure the SC should be putting out about 5-6 psi into a 1.2 liter engine, restricting to 75% might put me where I want to be... it's a good place to start. Yes, I could play with pulley diameters. A restrictor plate will be a LOT easier to tune with. If I end up with more than a 75% restriction... then a pulley change might be in order.
5. Driveway test. Is the boost as expected? Is the fuel as expected?
6. If the Driveway test checks out, then start street testing while monitoring boost and AFR. Casual light-throttle driving first, then moderate throttle, throughout the RPM range. If that all checks out, then some WOT at low RPM. Say, pulls from 1500-3000. If that's good, go to 4000. If that's good, go to 5000, and so on.
7. Full 1500-6500 WOT street test. (again, top of 2nd is 55 mph, not hard to find a place to do this)
B. Spend $80-200 or more to have someone verify that my AFR's are where I already know they are and tell me how much more power I'm making.

Am I missing something? If boost is out of spec, I'll adjust the restrictor plate to get it where I want it. If fuel is out of spec, then I'll lower the boost goal... and if that doesn't cut it, I'll look at ways to get more fuel (and decide if I really want to do that or not). I'm not just going to blindly slap the SC on the car and go run it to redline without giving it some thought and careful testing. I'm not stupid. (well, one could say that buying the Mirage to autocross in the first place was stupid...)

How is it "easier" to go add dyno sessions to my process? And what do I gain from it besides statistics (actual HP and torque figures) that I really don't care about? Maybe it would be different if I wasn't working with a streetable car, or if I needed to test at higher speeds. But, for my purposes... I'm just not seeing the need. Nor am I seeing it as "the hard way". I get to do what I need to do as far as testing and tuning on my own time rather than scheduling and paying for someone else's time.

It would be VERY different if I wasn't going to tune it myself, or didn't know what I was doing, or if I didn't trust myself to do what I need to do in a manner that's safe for both me and the engine. If I wasn't going to tune it myself, sure... let the tuning shop handle it. But, that's not how I roll. And I wouldn't spend that kind of money on THIS car!

I guess if I wasn't going to install any gauges or do any testing on my own, then some dyno testing would be a REQUIREMENT to be able to safely do steps 5, 6 and 7. But, with my own gauges to monitor those things... nah.

Keep the goals of the project in mind. Just a MILD increase in power for MINIMAL cost and effort, to have a LITTLE more fun with a RIDICULOUS little car. Not trying to set any records, or make a rocketship, or impress anyone with numbers, or blow up the engine. Just want to make it a tiny bit more fun to drive. It started out as a 0-60 in 10.5 second car. Now, it's maybe 9.5 seconds. With 3 psi... maybe it'll get to low-mid 8's? Fast? No! A little bit more satisfying to drive? Yeah.

[nathanwilliams617]

I just want "some" power, and to be sure my AFR's aren't too lean.

I think Loren is afraid the Mirage won't be able to spin the drum and it will stall. It probably won't measure that low. I've never seen anyone run a bike on a dyno. Maybe they have one at HD for a trike? [emoji38]

Lol

[twistedwankel]

... maybe it'll get to low-mid 8's?

When you use "Tim" and "mid-8's" in the same discussion we think you mean in the 1/8th mile. If anyone can make a roller skate more fun it's the Professor.

[Loren]

Okay, got the car back in the garage. Got out the tape measure and took some reference photos. Time to do the couch fitment verification!

It's going to be closer than I thought. I'll likely have to mount it ABOVE the intake manifold, which limits available space. Otherwise, shouldn't be too bad.

Analysis Mode - engaged.

[Loren]

Okay, thinking out loud again...

The SC is 7" long from the end of the pulley. This means the last 2" of it will definitely have to go over the top of the intake manifold.

If I mount it with the inlet and outlet on the top and bottom (it can be mounted in any direction), the height of the SC itself is 5.1". I have 7.5-8" (less toward the front of the car) of clearance between the fuel rail and intake manifold to the hood. The top flange will need to be fairly compact and either point straight toward the left side of the car, or straight back (depending on whether it's inlet or outlet, which depends on which way the blower is turning... it can turn either way). The bottom flange should be able to point straight down or with a slight forward angle with plenty of clearance.

The width of the SC oriented in this manner is 7.9", and I have an easy 9" of clearance from the oil cap to the radiator support.

If I turn it 90 degrees, the inlet and outlet will be at the front and back of the SC, which would probably make hose routing a lot simpler. Going that direction, the height becomes 7.9"... I need to take a better measurement of my hood clearance to see if that's going to be a problem. (or... I could just mount it that way and put a retro DSM "power bulge" in the hood!) Width would absolutely not be an issue in that direction. Aside from possible hood clearance, that's probably the easier way to mount it.

So, bottom line: Yeah, it'll fit. I just need to get my hands on one to REALLY see how it's going to fit. Also to figure out which way it's going to spin, and which side will be my inlet and my outlet for hose routing.

Belt routing will be fun to figure out. I'll need an idler pulley in there somewhere. The alternator tension adjuster is close enough to the front end of the engine that it can still be easily used to adjust tension. I may need to fit a longer alternator bracket to allow the alternator to be rotated more toward the front of the car. This will lower it down a little, and also move its pulley forward... making a little more room for the idler pulley. I'm really not sure how "fussy" that's going to be without having a part in my hands to throw in there to visualize how things are going to fit.

Looking under my hood, I also realized that I need to think about the PCV system. Did some quick research on that, and it seems like the easy button solution there is just to be sure that the PCV is hooked up on the inlet side of the SC so that there is no risk of it ever pressurizing the crankcase. That should be easy enough, just plug it into the SC inlet pipe. After the MAF, so that it doesn't contaminate it, and its air has been metered already. Possible contamination to the SC itself, but no more than the throttle body already sees... which ain't much.

Is it... time to order an AMR500?

Well... let me look into whether I can get valid AFR data out of my OBD reader first. I want to be sure I have a chance of pulling this off without fuel management first. If I need to, I may just do the AFR gauge first. No point in ordering parts if I don't think I can support the fuel requirements.

[twistedwankel]

Is it... time to order an AMR500?

No. Saroya will still spank your asses ( 2 driver car) and she hasn't done shit to her car in two years. If I volunteer to co-drive her car as a tire warmer rather than finish 6th or 7th in S1 your asses will be tanned while holding in a fart.

[Loren]

If/when I add boost, I won't be in M4 any more. If I was trying to be more competitive in M4, I'd be looking at camshafts and other NA mods that are allowed in M4. Cams are available, about 1.2mm more lift, $550 shipped. But, given what I already know about the valve springs... I really don't want to go there.

No, the boost project is purely a "just because" thing. I've tuned a boosted car. I've REMOVED a supercharger from a car. I've even helped install a few superchargers and turbos. But, I've never built my own SC kit from scratch.

[Loren]

Good news and less good news.

Good news is that the car does indeed have a wideband, and I can read it through OBD on the Torque app. Very cool. Very responsive.

Iffy news is that WOT acceleration is at exactly 13.13.

My previous research indicates that around 13.1 is precisely where you get the best NA acceleration. Most performance cars are tuned richer than that because it's "safer", and they're using excess fuel as a means of cooling the intake charge. If you've ever looked at the AFR on a dyno plot, they typically get up around 12.2 or even 11.8 at the top end. They're not stable, and they stay quite rich. At least the ones that I've looked at, which were mostly early Miatas. They were that way because the only feedback the ECU has is a narrowband O2 sensor at 14.7. Beyond that, it's flying blind, so they tune rich to be sure they never go lean.

So, I don't think it's that the fuel system in the Mirage CAN'T deliver more fuel. I think it's that it DOES have a WBO2, and it's using it to keep very tight control on the AFR. It WANTS it to be at 13.1 at WOT, and that's exactly where it keeps it. Pretty darned cool, really.

Now, the question is... do I want to run 13.1 AFR with 3 psi of boost? I kinda wanted more like 12.8. But, really... if I absolutely stick with 3 psi of boost, 13.1 is probably okay. How much is 3 psi? Atmospheric pressure is 14.7 psi. So, it's an increase of 20%. (which is why it nets about 15% more power after considering pumping losses)

Gonna have to think on that one a little bit more and maybe do a little more research. Open to thoughts.

[Loren]

Down the damned rabbit hole I go...

I'm just not sure about 13.1 AFR under boost. It would probably be fine, but I don't want to find out the hard way. Especially since I don't have any way to retard timing.

Soooo... I could throw a Microsquirt on it in fuel-only mode and get more fuel. That would cost me $400 or so. (ECU + MAP sensor + CLT and IAT sensors) That would give me control over the fuel. And if I really wanted it, I could also control the spark... but, I'd kinda like to stay out of that be.cause the ECU is controlling VVT, and I think it's probably best to keep spark and VVT control together. Not to mention that the stock ECU has a knock sensor, which the MS would not.

Another option exists. Maybe you've heard of it, it's been around for a while. The Unichip Q. Particularly, the Unichip Q4 (it has built-in drive-by-wire throttle control so that I can improve physical throttle response). It's a piggyback controller that interrupts outputs from the ECU and modifies them. So, say the ECU sends an injector pulse that's 50ms wide... the Unichip will output the same pulse, but make it wider, thus delivering more fuel. That's essentially all it does. Does the same thing for ignition outputs, throttle outputs, VVT outputs. It works WITH the stock ECU, so the stock ECU is still in control (sort of) and it doesn't cause OBD errors. But, you have some control over what it's doing. And, of course, it's tunable.

I've emailed the outfit in the Philippines that sells the Mirage SC kit. This is what they use to tune their kit. They do sell it separately. So, I asked some questions about it. Looks like their price on it might be over $600. (wholesale on it is about $380) That's a bit much, but it should include a base map that's been dyno tuned for a Mirage that's running more boost than I intend to run. That's worth a couple bucks. Potentially "plug & play", except that it's not "plug"... it's a hard-wired kit. 8 or 10 wires.

With that, I'd have the ability to set fuel (even put larger injectors if I wanted) and ignition, throttle sensitivity, even adjust the VVT... or the rev limiter. (scary)

Not saying I'm gonna DO any of this. I'm just exploring options. This can quickly turn my $900 project into a $1500 project. The potential for more power would be there, though.

And... I could buy the Unichip and do NA tuning on it as the car sits... probably get a little more out of it that way. Maybe stay in M4?

So many things to consider.

[Loren]

Still on the fence about whether I want to do this or not. Spent another few hours looking at other cars and such last night. I'm making myself dizzy!

The phrase "Life's too short to drive boring cars" keeps coming to mind. And that phrase can mean a lot of different things to a lot of different people. I could buy a Z06, and a lot of people would think that's not a boring car. Well... it's a FAST car. But, is it really an "interesting" car? I mean, if I spend that much money on a car, I'm not going to be modifying it much. And I wouldn't drive it on the street that much. It would become a garage ornament that I race on the weekends.

Contrast to the Mirage... which is clearly a SLOW car, but, it's been INTERESTING as hell! Perhaps those examples are the extremes for me. I don't necessarily need to be all the way on the Mirage end (and, yes, there are SLOWER cars than the Mirage... lots of them) of the scale. But, I'm not inclined to be on the "fast car" end of the spectrum, either.

I want a car that's at least marginally capable of being competitive in its class. A car that's small, reliable, cheap and economical. Easy to work on. But... preferably not older than about 2015.

Add to that... I want something that weighs as much below 2500 pounds as possible! It's a hard itch to scratch.

So... boosting the Mirage would make it even more interesting than it already is. There is that. And it meets every other requirement.

Oh, and I found another car that's in the "almost acceptable as an S5 car" category. In addition to the Hyundai Elantra GT Sport, and the Veloster Turbo whatever, there's the Kia Forte or the Forte Koup (2-door variant). Any one of those has around 200 hp and does 0-60 in the mid 6's... which I struggle with. I mean, I want it... but, S5 is supposed to be the "slow car" class... and that's not slow!

I need to go buy a Porsche 914 or something.

[Rawkkrawler]

there's the Kia Forte or the Forte Koup (2-door variant).

Slightly modified and you could also pull the trailer.

[Loren]

[Loren]

Didn't drive the Mirage today, but I'm one step closer to making the final decision to boost it.

It comes down to "Known vs. Unknown".

The Mirage is a known quantity. I know it's reliable. I know the platform. I know the suspension is relatively dialed in. I know that it needs NOTHING else to be enjoyable as both an autocross and street car. And I know it weighs 1900 pounds, which I really like.

Any of other options, especially if I buy used, are unknowns. Their reliability will have to be proven. I'll have to learn a new platform. The suspension is going to need work. Shocks, rear bar, and alignment at a minimum. And I DON'T know that I'll like the car until I've spent some time with it. And I DO know that most of them are going to weigh at least 7-800 pounds more than the Mirage.

The fact that the Mirage is a known should carry some weight in this decision.