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Socket wrench + a cheater bar are your friends, assuming the screw has a hex head.

It's a Phillips screw - you'll probably mutilate the head well before anything else. That's exactly what happened to me on one particular bolt, well known issue.

I'll probably get myself a really big phillips bit, put it in my 120V power drill, and put as much force as possible on it. Only way I can think of that might work (I stripped the other, and had to drill it out).

When I'm fighting a seized screw, I have much better luck with hand tools than with a drill motor. Put the appropriate screwdriver bit into a nut driver or hex socket, put a ratchet on the end of the nut driver or socket extension, and let leverage work for you.

Remember the #1 rule of mechanics.....

Don't force it, just get a bigger hammer.

JustAnEngineer wrote:

When I'm fighting a seized screw, I have much better luck with hand tools than with a drill motor. Put the appropriate screwdriver bit into a nut driver or hex socket, put a ratchet on the end of the nut driver or socket extension, and let leverage work for you.

On second thoughts, yeah, that might work as well.

Key being that I need to put a ton of force onto the screw as I turn it. (I tried to use a regular screwdriver last time... bad idea. Although it worked for 2 of the screws, just not the third. Actually, that door lock actuator is still being held in via only 2 screws, a few months later... shows how much it actually needs the torqued-to-hell third.)

Yes, a lot of the automotive Phillips screws have a hex head that a socket does much better on than a screwdriver. If you are stuck there is always an Impact Driver although even that can have problems with Honda brake rotor screws, drilling out is the last resort.

notfred wrote:

Yes, a lot of the automotive Phillips screws have a hex head that a socket does much better on than a screwdriver. If you are stuck there is always an Impact Driver although even that can have problems with Honda brake rotor screws, drilling out is the last resort.

...and if you're working on a '98 Corolla, using the hex head socket breaks the head of the screw off. Been there, done that.

Sunday was a pretty good day.

So as to not clog up dymt any further... http://blog.caranddriver.com/a-tale-of- ... l-economy/

Especially this:

Miraculously, I always average EPA numbers (older Civic, can't beat a new CVT's mpg), even though I tend to cruise at ~75 for most of the drive to CA (one week ). And I just rev up and maintain speed up the straight/wide/easy hills (a bunch of those are 3 lanes just north of Redding), just because I can. I'd love to test this and cruise in the 50's, but I just know I'll get tired of that real fast...

Whoever said driving fast doesn't save much time, well... we're talking hours difference here.

One thing that'd be nice to see is a brake specific fuel consumption graph for both engines, so that an optimum RPM vs. horsepower vs. BSFC graph can be made. (On a naturally aspirated engine, the general rule is, keep the RPMs down, and the throttle as far open as you can without going wide open (so as to avoid wide open throttle enrichment). On turbo engines, the rule is to avoid going too far into boost, so as to avoid boost enrichment, but sometimes that's hard to do at low RPMs.

Definitely.

You know, I always wonder - there are certain borderline scenarios where I'm not sure whether to upshift or not. (And automatics do the same thing - they'll hop up a gear if you let off the throttle, then back when you push it a little.) Ex. One of those is a very, very slight grade at 28-30MPH. Going down I use 4th (revs are pretty low, but I'm applying minimal power), going up I need to use 3rd. In my mom's auto, I end up riding the brakes the entire way down.

Thing is, you want to keep revs low, but I've heard that's not always best on a small engine/small car/low torque. Not sure how much throttle position has to do with fuel - if I can upshift (reduce revs) but I have to hit the gas harder, am I actually saving fuel? I've been getting better at ignoring the tach, hitting the gas a fixed amount, and upshifting when it stops accelerating as hard - seems to be smoothest.

I also noticed that, yeah, a moderate amount of throttle seems to be best on a lot of cars - get up to speed quickly, then shift into a high gear. Sounds similar to CPUs (i.e. get to a low clock quickly). Although my car does seem to get very perky when I go WOT on it (a little less and it doesn't).


Time to plug in my OBDII adapter, and mess around with this on the way back to CA.

localhostrulez wrote:

a moderate amount of throttle seems to be best on a lot of cars - get up to speed quickly, then shift into a high gear.

Yup.

When accelerating, look at your engine's torque curve if you can find one. Plot torque per rev and it'll peak somewhere low for anything with a turbo, and a lot of simple engines that lack variable valve timing. Realistically though, most modern naturally-aspirated engines have VVT of some type that will boost the torque per rev peak to much higher in the rev range.

It's not unusual to see this peak at well past half the redline, so if your car has a 6000RPM redline, you could find that peak torque efficiency is at 3500RPM, so you'll want to upshift at say 4500RPM because it's getting more force out of the fuel per cylinder stroke than it would be if you shifted up at 3000RPM.

If you want maximum acceleration you look at the torque curve.
If you want maximum efficiency, you look at the torque/revs curve.

Hey, if you can find a torque curve for a d17a1 (or even a d17a2, will be different in the higher revs because vtec), I'd love to see it! I've been looking, but sadly, no one seems interested in this (i.e. it's a slowish car to begin with).

That said, http://www.hondacivicblog.com/honda-engine-list/ says that it has max HP at 6100rpm (redline is 6800), and max torque at 4500. Depending on what I feel like, I usually upshift around 2500-4500 in the city (often on the higher end while getting out of 1st so that I'll have power in 2nd, then lowering it for later shifts). On the highway, usually 4000-5000, but sometimes I floor it and shift near redline if I feel like having fun. Cruising is 3000 at ~73MPH.

I dunno, I've heard WOT is efficient, except for the FI enriching the fuel/air mixture. Although it might explain why the hills on I-5 (near the CA/OR border) don't seem to hurt my overall mpg - engine has higher load going up (could be efficient for the power it's outputting), and then uses next to nothing going down. I mean, for example, 18mpg up the hill, and ∞ going down (FI turns off) averages to ~36.

Boring family cars are rarely dyno'd but you'll find this is the typical shape of a torque curve for a naturally-aspirated engine with a fixed, SOHC like your D17A1 (beware the non-zero axis start!)



The implementation and effect of DOHC in non-performance cars is usually to improve low-end torque and flatten the curve out a bit for a wider band of useful torque.



Without variable valve timing or forced induction to complicate things, there's not a lot that differs between torque curves of NA I4 engines other than the bore diameter and stroke length; Short-stroke, wide-bore usually gives you a curve that leans to the right of the graph with less torque dropoff at high RPMs, whilst the longer-stroke, narrow-bore usually gives you more torque earlier but a quite dramatic drop in torque at higher revs.

The D17A1 looks to be a long-stroke engine meaning that your engine's curve will probably be peaky, like the top graph. Notice the fuel-economy graph along the bottom: This example has peak torque at 4400RPM but fuel-efficiency is pretty linear from 2500RPM right up to its torque peak. After that the economy dropoff is pretty acute.

Ooh, nice!

It's kinda funny when I feel the horsepower curve - take my mom's '11 CR-V (5-speed auto, DOHC VTEC/VVT), turn onto the freeway at just the right speed so that it'll jump to second but not have super high revs (it really doesn't want to downshift to 1st), and wait as it slowly climbs into the higher revs and starts accelerating decently.

The curious thing is I shifted from 3rd to 4th while doing 30MPH once, so something like 2300 down to 1700 RPM, and Torque said my instantaneous mpg improved - the top graph seems to suggest it should be marginally worse. Although if I go off the feel and sound, the engine often sounds "happier" if I don't unnecessarily keep the revs high. (Plus, there's something in me that really, really wants to upshift to get rid of the droning in those cases. )

My next question is AC compressors - how do they handle the engine's rev varying? Seems like my car's AC is generally a fair bit stronger if I hit the freeway and sustain 3000RPM or so, vs ~2000 in the city. Seen this in the cr-v as well (newer, considerably lower mileage). Today is ~100F (a heat wave for the area, but nothing I haven't seen in the bay area). Threw a cheap temp gauge in there, and I measured 137F when the car had been sitting around. (Enough to temporarily somewhat blank out the cheap, crappy LCD on it! ) If I put a gauge in the air vent, it slowly goes from 80F and down to 60F or so in ~7 mins of driving - guessing it can handle a long highway drive of this just fine (more time, higher revs), especially on recirc. Air in the car was still 100F though, not in the vent (a considerable improvement at least).

I'm guessing people in Arizona need stronger AC than that though.

Yeah, if your instantaneous MPG is better by shifting down and using lighter throttle, shift down.

The trick to that BSFC curve is that it's not reflecting BSFC everywhere, just either best BSFC at that RPM, or BSFC at maximum power/torque at that RPM. A true BSFC map looks something like this (this is not for your car, this is for the Volkswagen ALH engine code, 1.9 liter 90 hp diesel with variable vane turbocharger and distributor pump):



BMEP directly relates to torque, so that's how you can calculate the overlay for HP.

And, yes, some AC systems need more revs to work well than others.

just brew it! wrote:

Rentals with automatics were difficult to find in Ireland when we were there ~20 years ago. I asked for one (I figured driving on the wrong side of the road was going to be challenging enough without also having to shift with my other hand), but no dice, all they had was stick. Add narrow country roads and roundabouts to the mix, and driving in Ireland was pretty stressful.

Had the same experience once I rejected the Mercedes they had with an automatic. I found the most difficult thing was simply understanding directions - got lost in Dublin the first day. After that, figured out that the shoulder by the window went to the center line so that I didn't have to think about which side of the road, and it was a piece of cake. The only thing that bugged me was that while the choice of arms for the gear was reversed, the gate pattern and foot arrangements were not.

Cuhulin wrote:

just brew it! wrote:

Rentals with automatics were difficult to find in Ireland when we were there ~20 years ago. I asked for one (I figured driving on the wrong side of the road was going to be challenging enough without also having to shift with my other hand), but no dice, all they had was stick. Add narrow country roads and roundabouts to the mix, and driving in Ireland was pretty stressful.

Had the same experience once I rejected the Mercedes they had with an automatic. I found the most difficult thing was simply understanding directions - got lost in Dublin the first day. After that, figured out that the shoulder by the window went to the center line so that I didn't have to think about which side of the road, and it was a piece of cake. The only thing that bugged me was that while the choice of arms for the gear was reversed, the gate pattern and foot arrangements were not.

Yeah, I made a lot of wrong turns too. My brain was constantly reversing left and right on me when it came to driving directions.

Roundabouts were bad because you need to operate both the gear shift and turn signal with your left hand. "I need to signal... wait, I also really need to get out of 1st gear... SH*T!"

bhtooefr wrote:

Yeah, if your instantaneous MPG is better by shifting down and using lighter throttle, shift down.

Here's a confusing case though - if upshifting means I have to press the throttle harder, am I still saving fuel? (After all, the revs drop.) Assuming the revs aren't ridiculously low when doing so.

I wish I had an instantaneous mpg gauge - best I can do is the Torque app and OBDII. To make matters more confusing, all my stuff is on my iPhone, but I need to use an Android phone for Torque/that adapter, so I'll need to mount 2 phones in the car. And there's definitely nothing prebuilt for that (I couldn't find something I like as it is). lol Time to 3D print one of my own I guess, if I can find time.

There's also the risk of draining the battery, hence why I never leave the OBDII adapter plugged in, and then I get lazy and continue to not use it... really should for the trip home though. Maybe see if I can log data. That'll be fun to look through later.

Cuhulin and JBI... A few weeks ago, I was at an intersection. 2 lanes going the other way, I'm waiting in the single left turn lane, two lanes going forward my direction. And there's a car sitting in the lane left to me (yes, that's the wrong direction), also waiting to turn. The guy then turned into a neighborhood street a few blocks later, and *again* went on the wrong direction for a little while before correcting. Must be an international student or something. Eek!

There's always switching to a ScanGauge II or ScanGauge E, which is designed to be installed and left in a car. (I'm considering getting a ScanGauge II myself - it'll be handy for seeing whether my change in strategy is actually working as well as I think it is, on my Miata, as well as for the car I'm planning on replacing my Golf with (2016 Prius), monitoring what the hybrid system is doing, using XGauges.)

As far as upshifting and pressing the throttle harder... in a naturally aspirated engine, it often does mean better fuel economy (but not always, it depends on things like cam timing, fueling strategy, EGR activity, that kind of thing). Lower RPMs means less frictional losses, and wider throttle opening means less pumping losses (the engine suffers drag due to sucking air around the throttle plate when it's less open).

Welp, I did it.



Looks like I need to take yoga classes, so I can get the flexibility to smell my own farts.

bhtooefr wrote:

Welp, I did it.

img

Looks like I need to take yoga classes, so I can get the flexibility to smell my own farts.

Try not to be too smug about it.

"Smug Alert!"- Wikipedia

Finally found an annoying point with the '16 Subie Forester XT. The stereo sounds great and has all sorts of options (SiriusXM, Pandora, a few I don't recognize). It even has a USB input.

Just try to plug in a USB drive with WAV, FLAC, or any other lossless files. Silence. The bloody thing only groks lossy MP3/WMA/AAC (I tried lossless WMA, no go). Yes, it's got an aux jack, but there's squat-all for players out there that can store the roughly 400GB of my lossless music that aren't megabuck (literally) stupid high-end players.

How ruddy difficult is it to decode WAV files on the USB input when there's a bleedin' CD player built into the fargin' unit!! At this point Subaru is making the Sirius Cybernetics Corporation look like coding geniuses, and my inner Ford Prefect is getting twitchy.

^ A few years back, I successfully installed a 240GB HDD into an iPod classic. I couldn't tell you the model number offhand, but it was a one-off Toshiba 1.8" with what I believe was the micro derivative of a PATA interface.

I doubt the drive is still available, but that's no matter, as I believe folks are now using adapters to plug in large flash-based cards.

Ned, how good is the Subie's sound system anyway?

At least in my Civic, I can tell the difference between 96 and 160kbps Spotify streaming (just enough to question things when it's at 96 - i.e. "I swear CDs are clearer in this car"). Beyond that, not really - it's not a particularly quiet car anyway.

I wouldn't mind installing the tweeters from the higher trim someday, if I can figure out how...

localhostrulez wrote:

Ned, how good is the Subie's sound system anyway?

I love the Harmon/Kardon system that comes with my trim level. It's as good or better than the top-line system I paid $3,000 for back in the late '80s. The kids on the Subie boards hate it because it won't rattle the Bondo off the riced Civic in the next lane but if your musical tastes don't extend to tribal rhythms, you'll do just fine. Non-nav cars get a bass/mid/treble slider setup for tweaking, while nav cars get a 10-12 band EQ with saveable presets.

Let's see... I drive a Civic and like to rev the hell out of it when getting onto the freeway(sometimes with rap music), but drive reasonably otherwise/try to maximize gas mileage/reduce wear on the car/keep the car stock. Not really sure what camp I fit in. The stock stereo can't rattle the suspension or anything (although you can feel it/see the mirror vibrating), but it's sufficient to be obnoxious on a basic level.

So I've been driving stick for like four years across two cars and I'm still not sure how to engine brake 'properly' - like should i immediately go down to lowest gear possible to slow myself (rev matching) or what? 

pikaporeon wrote:

So I've been driving stick for like four years across two cars and I'm still not sure how to engine brake 'properly' - like should i immediately go down to lowest gear possible to slow myself (rev matching) or what? 

Next gear down for stronger speed reduction, with enough proactive slowing, you can coast or foot off the pedal very early to feel the drag, think hypermiling. Upgrade your brakes (vented only is typical for stock, upgrading to slotted/drilled will improve stopping and reduce brake fade- upgrade from stock whenever possible, e.g. 2000 GTI GLX VR6, fitted with drilled and slotted rotors, mintex redbox pads.

Still rocking the 10-year old Corolla. Might be upgrading to a new-ish convertible in the spring. Most likely a Mustang. Need something with four seats or else I'd go with a Miata, but need the flexibility as the backup car when the wife's is in the shop.