Transmission options.

[Ecky]

Originally Posted by Mista Bone

You should be using the GSR 5th but with ECU tuning you can get by with the higher rpms. LS motor with bigger bore is happier at a lower cruising RPM, but that is getting into some engine dynamics that isn't understood here.

Imagine doing 70 mph in 4th gear and getting 47+ mpg.

Vacuum gauge and driver mod is the first and best gains, then ECU tuning.

Myself I tend to use very light throttle, enough to pulled to 3500 rpm, then shift to next gear while not lifting off the gas pedal.

I hope to set up a video camera in the car to show how I drive the CRX and my old HB, then maybe others will understand.

Appreciated. I'd love to swap out my 5th for an LS 5th but I don't think I have the proper equipment to drop the tranny in my apartment complex parking lot.

Just went out and sat in the parking lot and rev'd the engine in neutral (fully warmed up), and measured the fuel used. These are the figures I came up with, which I bet are accurate within about 10%:

Idle/750RPM: 0.22 Gallons/hour
1000RPM: 0.28 G/h
2000RPM: 0.50 G/h
3000RPM: 0.91 G/h
4000RPM: 1.10 G/h
5000RPM: 1.50 G/h
6000RPM: 3.04 G/h



Possible parasitic loads are power steering, a fully battery with minimal electrical load, oil and water pumps, internal friction, pumping losses.

For reference, cruising at 75mph (4000RPM) I get around 30MPG (or I did before my recent aeromods) which calculates to approximately 2.5 gallons per hour. 65MPH (3500RPM) / 37mph is around 1.9G/h. 38mph (2000RPM) / 47MPG is around 1.24G/h.

[Mista Bone]

Free revving is not a viable way to measure. Also at which points was the ELD turning the alternator on/off?

There is much to teach here about engine dynamics, many gains to be had.

[Ecky]

Originally Posted by Mista Bone

Free revving is not a viable way to measure. Also at which points was the ELD turning the alternator on/off?

There is much to teach here about engine dynamics, many gains to be had.

I can see the alternator turning on and off because the revs dip, these were measured when it wasn't dipping. However, you're right in that it's quite complicated, and I'm not able to measure things like AFR, I have no idea what the efficiency is at a given RPM, and free-revving doesn't tell us anything about horsepower under load.

I'm sure there's at least something to be gleaned from this though.

[user removed]

The law is Federal. Read it an interpret it for YOURSELF.

Can I get into trouble if I disconnect any of the... — Yahoo! Autos

Any non DOT approved modification is considered tampering. It has nothing to do with your state and nothing to do with passing any state mandated emissions testing. If you installed or modified any emissions component and it was not DOT approved you are in violation of Federal law. Read it for yourself. Remember when you are summoned you start spending money and you are persecuted (or prosecuted) based on the judgement of a govt employee who could care less about what it cost you. Even if you prevail you are still loosing. Even passing an emissions test does not prove your case.

I owned a Del Sol, a CRX and my VX. Regularly got in the mid 40s for mileage in the Del Sol. No need to defend yourself. I am not attacking your work, I actually admire your accomplishments.

I would just be careful about making it public until you have made sure you are not risking unanticipated consequences (very unlikely but possible). I posted earlier (I believe in this thread, but possibly in another) about being aware of the 1990 changes in the linked law that extended the potential fines to owner modifiers. I can't possibly know whether you were aware of the law and complied with it's provisions when you changed the ecu programming. Personally I think your work is admirable, but just cover yer arse as we say round here.

regards
Mech

[user removed]

When they came after me I had proof of compliance. I wouldn't wish that on any poor citizen.

My build is legal in every aspect of which I am aware and I have done it before.

I owned the Del Sol before you ever started messing with creating lean burn in an engine that was never legally lean burn capable in the US and never was DOT approved, thus your operating it in lean burn was technically a violation. Best tank in original (legal) configuration was 47 MPG.

I am finished with your threadjack. If you don't want to listen to experienced free advice, then at least don't drive another nail in your potential coffin by posting it publicly.

[California98Civic]

Pgfpro, I'd love to see you start a thread that makes the case you just posted in #50. It seems like an interesting assertion, using equipment not many of us have access to (I think). But buried in this transmission thread and positioned as a back-and-forth with Old Mech I think you're not getting any audience. Make a thread with a title that will tell people what's at stake and lots of new eyeballs will see what you're trying to say.

EDIT: wanna add too that your questions are interesting, Old Mech has expressed admiration for your work on that car, and I also dig it. On D-series the reactions to your build were priceless cool.

Respects,
james

[Mista Bone]

I thought VE was a constant, never above 100%???

(sarcasm)

So "what if" best BSFC came at 20% throttle at 70% of the peak TQ rpm?

Airflow through the engine is just as important as airflow around the car.

[Mista Bone]

Originally Posted by pgfpro

Ha ha!!!

Now don't spoil the fun.

Inconceivable

[P-hack]

Originally Posted by Mista Bone

But drop the hammer and the car isn't boring anymore. I drag race and autocross for fun.

Lol, it sounds pretty droll. If you eat that cake, you don't have it anymore, the fuel spent on frills is gone, and the rest of us will see you at the next red light (or pass you at the pump/or while you are getting pulled over).

Anyway good to know my ex has the WORST transmission for fuel efficiency :/

[Honda]

Update:
I bought the transmission I was talking about but it turned out to be from 1999 Civic EX.
At the same time I put stage 1 Exedy clutch, light weight flywheel, 15'' alloy rims (heavier than stock).
I know that some of the above may not help to increase FE but I wanted to see what will happen by transferring the inertia from the flywheel to the wheels.
The car traveled farther while on neutral but the overall MPG dropped from 37 to around 34, could be the cold weather is to blame I don't know.
While driving at 65mph the rpm is around 2700.
I am still shopping around for obd1 trip meter that can help me get more accurate result.
Also I couldn't use the highway most of the time due to HOV, so I was stuck in traffic in the morning.