The Scrapcento

[AndrzejM]

Originally Posted by maczo

OK, my bad. Not all mods welcome, I will restate that I don't want to compromise performance.

So go for weight reduction, it will increase your performance, and FE

WAI could be de-installed quickly for events.

That can be done easily

How much of a gain would DRLs give me?

55W per each headlight, 5W per each front position light and 10W per each rear position light so it will be 140W depending on alternator efficiency the gain will be between 0,2 to 0,3 HP

I'm thinking more and more about the vacuum gauge. Am I right that the rule to follow is:
a) when accelerating, aim for the least possible vacuum (small negative numbers)
b) when maintaining speed (i.e. on highway), aim for most vacuum (large negative numbers) in top gear
Right?

For FE it's good to maintain high vacuum for all the time

[Piwoslaw]

Originally Posted by AndrzejM

55W per each headlight, 5W per each front position light and 10W per each rear position light so it will be 140W depending on alternator efficiency the gain will be between 0,2 to 0,3 HP

DRLs would work nice with an alternator delete, or at least alt on/off switch. During races you could take the alternator belt off, which would free up not only the electrical load, but also mechanical belt losses, probably ~1-2hp total. Just make sure you have a healthy battery!

[maczo]

Originally Posted by AndrzejM

So go for weight reduction, it will increase your performance, and FE

The no. 1 weight-saver would probably be removing the spare tire, but then I wouldn't feel to confident in case of a flat tire in the middle of nowhere. I do have a spray-can ad-hoc sealant but I'm not sure this would suffice. Any thoughts/experience on that?

Originally Posted by AndrzejM

[with DRL] the gain will be between 0,2 to 0,3 HP

Will that have a measurable influence on FE? I think most notably it will decrease the idle consumption, so with P&G maybe also a bit improve real-driving FE just that tiny bit. But is that on the order of 1% even?

Originally Posted by AndrzejM

For FE it's good to maintain high vacuum for all the time

I was thinking high vacuum reading would mean high engine load and (assuming low RPMs) optimum BSFC. Is this true?

Originally Posted by Piwoslaw

DRLs would work nice with an alternator delete, or at least alt on/off switch. During races you could take the alternator belt off, which would free up not only the electrical load, but also mechanical belt losses, probably ~1-2hp total. Just make sure you have a healthy battery!

Soooo... P&G = alt off, DFCO = alt on? Rinse and repeat?

As for belt off, I think it will be risky for Saturdays. Usually there is quite a lot of driving and the schedule is tight. This means no room for battery going dead. But fur Sundays' super-stages that might be a viable option (if it's not violating the rules, which I think it should not). I just need to see how much work it takes to remove and re-mount the belt.

[AndrzejM]

Originally Posted by maczo

I do have a spray-can ad-hoc sealant but I'm not sure this would suffice. Any thoughts/experience on that?

Nope, nothing.

Will that have a measurable influence on FE? I think most notably it will decrease the idle consumption, so with P&G maybe also a bit improve real-driving FE just that tiny bit. But is that on the order of 1% even?

Every bit counts, you can do something and gain 1% or do nothing and burn more fuel. Of course sometimes getting another 1% will cost you $$$ and it's not economicaly justified, but since DRL's aren't heavy for your budget and you'll get few bucks back from bulbs that you won't need to replase to often, I think that's worth trying.

I was thinking high vacuum reading would mean high engine load and (assuming low RPMs) optimum BSFC. Is this true?

"Sweet spot" is one thing, and high vacuum is the other. You can't drive always witgin BSFC rev range and then you should maintain high vacuum. It meens that the throttle is closed as much as possible to maintain your speed.

When I was driving Prevka (http://ecomodder.com/forum/showthrea...via-19600.html) I've noticed that after I've got to the speed I needed, I could actually let the pedal go a bit with noticeable difference in FE, without slowing down. So I could drive the same speed with two FE readings.

As for belt off, I think it will be risky for Saturdays. Usually there is quite a lot of driving and the schedule is tight. This means no room for battery going dead. But fur Sundays' super-stages that might be a viable option (if it's not violating the rules, which I think it should not). I just need to see how much work it takes to remove and re-mount the belt.

Just make sure that the belt is not pulling water pump together with alternator.

[maczo]

Today a bit off-topic.

Took a 850km trip with a borrowed Opel Astra with a 1.7 diesel engine (CDTI probably) and a 6-speed gearbox. Talk about effortless FE! Of course I couldn't resist and slapped a piece of cardboard on it


I don't know if it helped, but in theory it should have, right? The final result: 4.8 l/100 km over 850 kms. I just can't imagine doing this trip with the 'cento. It would either take twice as long or end up burning almost twice as much fuel while being quite noisy and not that comfortable.

Also, an interesting vessel that I caught.

[MetroMPG]

You know you're an ecomodder when you stick cardboard mods on a borrowed car.

Neat solar pontoon boat.

[maczo]

Back to the 'cento... In the past 2-3 weeks or so I've done about 500m (yes, meters) with it: from parking spot to the mechanic, back to parking spot, then back to mechanic. Hope to get it back working tomorrow. Good thing I walk to work

I went with Andrzej's advice and removed unnecessary stuff from the trunk, most notably the spare wheel (replaced it with the spray sealant and now hoping for the best). I'm not expecting this to show in the fuel logs, as the temperatures have fallen significantly since my last fill-up (which was back in September!). On the plus side, I already switched to winter tires, which are quite slim (145 vs 165).

Also, I've decided not to go the DRL route, at least until my driving patterns change. I thought about where and when I usually drive, and came to the conclusion that for the 90% of cases it's after dusk, so DRL's potential gains could not be realised in a reasonable timeframe.

[Sven7]

What kind of winter tires did you get? 145 is very hard to find, in any diameter. But a nice tire if you're rallying in Sweden

[maczo]

Originally Posted by Sven7

What kind of winter tires did you get? 145 is very hard to find, in any diameter. But a nice tire if you're rallying in Sweden

IIRC they're Fulda Kristall Montero, the size is 145/70R13 and it's pretty common for smaller cars where I live.

Would love to rally through snowy Sweden on spiked tires. I'd probably end up on a tree pretty quick though

[maczo]

P&G: you're doing it wrong

That's my conclusion after I changed my driving style to pulse more aggressively. I believe this resulted in better coast-to-pulse ratio and my best ever FE with the car (6.4 l/100km, 36MPG). All that in much colder weather than the previous best (but with the help of narrow 145 tires).

Unfortunately today I drove into a deep puddle during Rally Barborka Bis, the engine died and made unpleasant sounds when I attempted to run it after a while. I hope it's going to live