slugbug
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Any suggestions on intake, exhaust, and tuning mods to improve mpg? I have a 2002 beetle with 135,000 miles, getting 45mpg. Thanks!
What are your driving conditions and which transmission?Any suggestions on intake, exhaust, and tuning mods to improve mpg? I have a 2002 beetle with 135,000 miles, getting 45mpg. Thanks!
Mike did a very good job. Back in the 60's you could make good improvement in power, and mileage by improving the intake and exhaust, but the auto makers found out about it and figured out it was almost free to make those improvements so today your car already has those improvements.The thing which makes (by far) the biggest change to MPG is to change driving style. Most physical mods only make a very slight difference….
5 speed and highway miles but i do idle in the mornig for 20 minutes to warm it upWhat are your driving conditions and which transmission?
Wow! Do the math! Hello! Thanks for your response. Keep the right foot light.Work out the dollars and cents until it makes sense. (I know, it sounded good in my head)
Diesel is, for round numbers, $4/gallon.
You are paying 400 cents for 45 miles, or 8.88 cents per mile.
If you increase your FE to 50mpg that works out to 8 cents per mile.
Annually, if you drive say,... 20,000 miles that 0.88 cents per mile savings equals:
17,600 cents.
Less than two hundred bucks a year.
How much do you want to spend increasing your FE from 45 to 50 mpg, with no real guarantee of averaging 50mpg. (+10% is very optimistic)
No idle is needed other than a minute or two at most.5 speed and highway miles but i do idle in the mornig for 20 minutes to warm it up
Like the others have said, skip this step. The best way to warm up the engine is to drive it (carefully, no big loads or revs while it is still cold). Are you having problems with ice? I use an icescraper on the outside (and sometimes inside!) of the windscreen, but haven't needed to do that for a couple of months now.... but i do idle in the mornig for 20 minutes to warm it up ...
Actually it is not the efficiency that keeps TDIs from warming up. It is the ultra lean burn at idle. The exaust gasses only come out at about 250F where as stoic idle in a gasser is about 1300F. This happens because the gasser restricts air flow to the point where only enough air to idle is allowed in where as the TDI flows the same amount of air whether at full throttle or idle and restricts the speed by limiting the fuel.
Yeah but they are talking about idling the engine in your driveway. Turbo is effectively invisible in this condition - no throttle, no VNT directing any exhaust flow onto the turbo, etc.Right idea but not entirely true, turbo pushes air in with throttle, so your flowing more air than idle, lol.
Bottom line is diesels use as much fuel as needed, and no more! Gassers run 8:1 at idle 14.7:1 at cruise. Diesels run about 40:1 at idle, and 18-20:1 at cruise.
The turbo is always spinning if the engine is running.Yeah but they are talking about idling the engine in your driveway. Turbo is effectively invisible in this condition - no throttle, no VNT directing any exhaust flow onto the turbo, etc.
No, sorry, plenty of gassers operate at stoich or leaner. Most cruise at that, and only run richer under acceleration. Civic VX, Insight and Toyota Prius all run leaner than 14.7:1, the Insight as lean as 25:1 cruising.Oh and FYI no gas engine would use a 14.7:1 ratio that would produce 1700F egts and burn your valves in a mater of minutes. even on titanium motorcycle valves we dare not go leaner then 13.5:1 and idle is generally set to 13:1 or 12.5:1
Dang it you guys just want to make this complicated
Turbo is powered by excesive heat in exaust gas. At idle the engine would acutally get more air with out the turbo in the way restricting air flow. but this is not important what is important is the mixture ratios.
For the first minute the egr is partically open so the engine pistions are not breating entirely fresh air. this air is warmer becuase it has been previously burned. the mixture at this time is probably closer to 30:1 and temps around 450 . After the first minute the egr closes to prevent suit build up and the mixture goes to 60;1 or 80:1 and temps drop to 250 ish. Stock full throttle is closer to 18:1. if you have a chip tune they get this down to 15:1. Crusing only requires about 1/2 the aviable power thus crusing would uses more like 36:1 (18:1 *2) but the egr recycles air and reduces this to more like 30:1.
Oh and FYI no gas engine would use a 14.7:1 ratio that would produce 1700F egts and burn your valves in a mater of minutes. even on titanium motorcycle valves we dare not go leaner then 13.5:1 and idle is generally set to 13:1 or 12.5:1
Invest in a scanguage and a taller 5th gear, LLR and lower your speed (left foot mod). This should get you at last 5-7mpg improvement.Any suggestions on intake, exhaust, and tuning mods to improve mpg? I have a 2002 beetle with 135,000 miles, getting 45mpg. Thanks!
Is that the hollowed out Beetle on bicycle tires in the video above?Also do the cage mod.
I just did the cage mods and the car ran smoother right away! I am thinking about using the dielectric grease in every contact point in the car since it cannot hurt.nIs that the hollowed out Beetle on bicycle tires in the video above?
Here in America, Is it not the "Right foot mod"?? LMAO!!Invest in a scanguage and a taller 5th gear, LLR and lower your speed (left foot mod). This should get you at last 5-7mpg improvement.
You are quote air/fuel mass ratios though arent you? you cant just use the ratios to say that diesels use less fuel...even if it is true. as the person you replied to said, petrols create a vaccuum using a throttle butterfly, so less air enters the engine. therefore for a given AFR less fuel than the same AFR at wider throttle settings.Right idea but not entirely true, turbo pushes air in with throttle, so your flowing more air than idle, lol.
Bottom line is diesels use as much fuel as needed, and no more! Gassers run 8:1 at idle 14.7:1 at cruise. Diesels run about 40:1 at idle, and 18-20:1 at cruise.
OOops you're right!Here in America, Is it not the "Right foot mod"?? LMAO!!