turbo for better mpg

[Firestarter]

Originally Posted by cRiPpLe_rOoStEr

BMW was involved in a project targetting the usage of an electric starter motor bolted to turbochargers to make them "fill-up" faster.

There are several problems with using a starter motor... they are brushed and well wear out quickly compared to alternator/brushless motors. High temperatures from the turbine housing will demagnetize the motor... high end rc car motors demagnetize around 240*f. That's internal not external temperature. One reason why you're not suppose to keep cranking your motor for too long. Turbos operate from 50-150 thousand rpm and good luck getting a 12.6 volt starter spinning close to add the necessary power. Not to mention the HP needed would put too much side load and could damage the bearings.

Not saying its impossible. But rather difficult to use existing systems. Probably needs a ground up design

[cRiPpLe_rOoStEr]

That electric starter motor for the turbocharger was not like the average starter. As far as I remember, it was supposed to be brushless, but I don't remember more details about this project.

[jm283611]

Originally Posted by baldlobo

go down to the LPT section of this page.

AutoZine Technical School - Engine

thanks for the link, thats kinda what I had in mind, if I just assemble it for little money is the topper, definitely on my list is the cx trans which has a 3.25 final drive as opposed to my 4.25 final drive, to drop my engine speed, even with the trans i have now i have to down shift for some of these "hills", everyone has a civic and always wants to out rice the jones, I'm hoping to snag and entry kit for cheap, the trans swap will be free if all goes as planned

[jm283611]

Originally Posted by serialk11r

Yea, you're already at 1.6L which is pretty small, 1.5 won't be worth the effort unless you need a new motor for some reason, and your gears aren't that bad. Your car profile says it's manual transmission, so I'd just work on driving technique and some light aeromodding, unless gear swapping is really easy and cheap. 2500rpm at 55...I'm jealous! I'm turning 3000, with a 1.8 too For my car at least, 5th gear swap isn't very popular because the 11% rev reduction doesn't add up to fuel savings that quickly and it costs 230 in parts to do alone. Swapping to a 6 speed makes a little more sense because at least you have improved acceleration and more choice of gears for around town. Don't worry about the hills, if you need to go down a gear just be sure to keep the load relatively high. You might discover that you don't need more power at all to stay in top gear! Ideally we'd all have super tall gears and forced induction but that costs money, so we just have to accept the loss of power.

65mph is honestly pretty fast already and you're using A/C, I think your gas mileage is quite respectable. I always go 50 if I can get away with driving that slow.

you cant sell off your parts after the swap? i know the ex trans is wanted by the ricer crowd, so i plan on just trading with someone, all i'm out is a little time, and my clutch, might as well while its open, also the ac is a must for me, black car, and the windows dont work lol, at 65 i already have truckers running me over, i'm a little scared to go slower

[jm283611]

update!! I've done some mods, lowered 2.5" and added a front lip, I'm regularly hitting the low 40's @60-65 mph. This Friday I will be swapping in a cx trans, and getting a good alignment