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Tue Oct 20, 2009 2:54 pm

I've done 31mpg highway with dual kads on a mexican 1600, same engine gets about 29 with aggressive city driving

Tue Oct 20, 2009 8:25 pm

Yellowbeard wrote: tundrawolf wrote: He also said with the right driving I could squeeze 38 MPG with the right tires,

Not gonna happen. The best mileage average I ever got was with my stock 1200cc 40hp in my '63 Beetle. 32mpg, mostly backroads, some freeway. My stone-stock '74 standard averaged 28mpg, mostly freeway, some backroads, some city.

I'm gonna try it. I usually don't go above 55 MPH and know how to milk the miles per gallon. Plus, full synthetic fluids and a rebuild on the motor, and tuning tips from the guy I worked for who has been wrenching on them for 30 years, I should get mid 30's at least. I have a 1600 given to me here, I just need a vehicle to go get it. The guy who was going to drive me there had a stroke. He's a good man and my prayers are with him.

Tue Oct 20, 2009 8:59 pm

tundrawolf wrote: Yellowbeard wrote: tundrawolf wrote: He also said with the right driving I could squeeze 38 MPG with the right tires,

Not gonna happen. The best mileage average I ever got was with my stock 1200cc 40hp in my '63 Beetle. 32mpg, mostly backroads, some freeway. My stone-stock '74 standard averaged 28mpg, mostly freeway, some backroads, some city.

I'm gonna try it. I usually don't go above 55 MPH and know how to milk the miles per gallon. Plus, full synthetic fluids and a rebuild on the motor, and tuning tips from the guy I worked for who has been wrenching on them for 30 years, I should get mid 30's at least. I have a 1600 given to me here, I just need a vehicle to go get it. The guy who was going to drive me there had a stroke. He's a good man and my prayers are with him.

Good luck. Hot Vws magazine and CB Performance tried to get 40mpg out of a motor custom-built for the purpose. And (barely) failed. 39.1mpg @ 55mph. And they spent quite a bit of coin on parts and engineering.
Read all about it:
http://www.cbperformance.com/articles.asp
http://www.thesamba.com/vw/forum/viewtopic.php?t=206968&highlight=mph+setup

Tue Oct 20, 2009 9:17 pm

Thank you.

I read that a while back... But I felt the same way a poster did about it: It seemed like as much of an advertisement for a part company as it did for a mileage motor. Twords the end they used a fuel injection system that's many many times larger than what would be necessary for our engines. Not super convincing to me.

I've talked to two VW people who have been working on them for 30 years (One a little less than that) who both tell me it's possible to squeeze 35 MPG out of a 1600. If they agree on that, I think I can do better with a 1300. Plus, the one mechanic specifically recommended the 1300 to me, right after I asked him about a mileage motor. Hey, time will tell. (I'll keep you guys updated on my mileage and driving habits)

Wed Oct 21, 2009 3:56 pm

Tundrawolf, there are those who will happily tell you what you can't do.

I've managed 33-34 in the summer with a basically stock 1600 in a 63-based Baja. Light car, light foot and lots of fine-tuning.

No shop can afford to apply the amount of time on a single car that a hobbiest can devote. Apply common sense as you experiment and learn from your own car.

http://www.thesamba.com/vw/forum/viewtopic.php?p=2701412#2701412

Max

Wed Oct 21, 2009 9:14 pm

Yeah, I'd say, try it and let us know. You never know - hell, I've gotten 40-43 MPG out of one of the 1385cc 40HP engines I've had in my 62 bug before, but that was with an extremely light foot, in the mountains. But my current such engine, even when I've really tried it's hard to get over 36. My baja with the 1600DP, even when I take it easy and stay under 55, I'm lucky to get over 30. Sometimes 31-32, but rare. Most of the time I'm not trying though, as I'm doing 65-75MPH on the hilly windy interstates out here nad only getting 22-25MPG.
-Andy

Wed Oct 21, 2009 9:20 pm

Gentlemen, thank you for the encouragement. I have a motorcycle that gets 50 MPG (At less than $5 a month for insurance) that I am trying to emulate- but offroad capable, and shedding about 8 pounds of clothing.

Glutamodo: Do you have any specifics on your particular 1385cc setup? I get the motor on Friday, and I can pick and choose what goes on it, I believe.

Max: I was told after I passed my DMV motorcycle test that I couldn't pass it on my heavy cruiser using only my front brake.. But I passed it nontheless. (Allbeit after many practices)

Thanks again.

Wed Oct 21, 2009 10:46 pm

The 1385 is the big-bore size on the "1200" 40HP engine. I probably should have just called it a big-bore 40HP, just a stock 64mm stroke crankshaft and oversize 83mm pistons instead of 77mm. The 1300 engine (1285cc) has the longer 69mm stroke, but 77mm pistons. The 69mm stroke engines have a lot more options for their intake and exhaust compared to the 1200/40HP. (I've always had big-bore 40HP engines in my 62 bug) I'd probably recommend a 1300, because of the more options for exhaust,intake,tin, etc... the old 1200/64mm stroke engine, parts aren't as common and just about nothing in the aftermarket for it anymore except those big-bore piston/cylinders.

One thing about the stock 40HP and 1300 engines, is that they were matched with transmission gearing that was lower than on 1500-1600 cars, and for a reason, the power range is matched better there. My Baja, while it still has its 61-66 era lower-final-drive gearing in it, has taller tires in back which effective makes the gearing taller, pretty close to what VW used in the mid 70s 1600 models. I once had to put one of my big-bore 40HPs in that car for just a few days, and man, I could certainly tell the difference, the taller gearing sapped the power, compared to both the 1600DP that was normally in there and compared to my 62 bug with stock size tires on it. It wasn't very enjoyable for me to drive. Better milage there, well, just from it being a smaller engine with small valve heads on it, it would get better milage, and the taller gearing might help out too, IF you didn't try to drive it harder to compensate for the gearing.

Again, it's a big combination act, engine size is just part of it. Intake/fuel, exhaust, ignition, gearing all combine together.

-Andy

Thu Oct 22, 2009 8:41 am

On our trip to Seattle a month ago, I documented an average 31mpg highway, with a peak of 33mpg between Yakima, WA, and Baker City, OR. Three people and bags, no less! (235 miles, 7.3gal used - I have receipts to prove it!) This, from a mild stroker! I can detail the build, if you'd like.

City mileage sucks, however. Been right around 24mpg, give or take. It's hard not to mess with the ricers!

What I think helped a great deal:
- New tires (B traction rating)
- Spot-on tire pressures (adjusted for weight, of course)
- Lowered the nose 3" (think it cut wind resistance from the nose-up SB stance)
- New wheel bearings, front and rear
- Careful brake adjustment
- Sensible, careful engine build, eye towards good mid-range torque
- 3.88 R&P and .89:1 4th

Thu Oct 22, 2009 9:54 am

My '64 Vert 1200cc gets 36 Highway and 32 around town. Worst I ever got in it was 28 because of my lead foot.

Thu Oct 22, 2009 12:48 pm

Alister wrote: ...City mileage sucks, however. Been right around 24mpg, give or take...
I wouldn't call that "sucking"....that's pretty average for around town.

Thu Oct 22, 2009 3:36 pm

Bierboy wrote: I wouldn't call that "sucking"....that's pretty average for around town.

True enough. I blame my lead foot and the tendency to 'demonstrate' how quickly an ACVW will get out of the hole!

Thu Oct 22, 2009 5:12 pm

People frequently overlook the affect of weather on gas mileage. As we move into fall and winter, it takes longer for the engine to warm up. The engine also runs a bit less efficiently in cold weather, both of which will cause mileage to drop. So don't be surprised to see your numbers go down without changing anything. Also, keep your tires properly inflated! Air pressure drops with temperature, and underinflated tires increase rolling resistance.

My personal best in my sedan is 34.7, last August. This was without trying too hard, mostly highway. With a little effort I'm sure I could have hit 36 or better.

It's possible. Have fun tinkering! 8)

Thu Oct 22, 2009 5:15 pm

I suppose tires do have a big deal ... filled up my tires the other day (20psi in the front, 22psi in the rear), retuned my carb, and changed my plugs and got a best of 29mpg with 50/50 "country" roads and "highways." (Two lane road with a speed limit of 55mph being my definition of a highway).

:)

Thu Oct 22, 2009 5:54 pm

DonnieDarko wrote: I suppose tires do have a big deal ... filled up my tires the other day (20psi in the front, 22psi in the rear)
Put 29 in those rears like VW recommends and you'll hit 30, easy.

Thu Oct 22, 2009 6:21 pm

mnussbau wrote: DonnieDarko wrote: I suppose tires do have a big deal ... filled up my tires the other day (20psi in the front, 22psi in the rear)
Put 29 in those rears like VW recommends and you'll hit 30, easy.

Er, I meant 32psi. My tires slowly leak air so I tend to overfill them by a few pounds so I'm not putting air in them more than once a week.

Thu Oct 22, 2009 6:48 pm

So for max mpg from an engine we are leaning towards something built on a 1300?

Thu Oct 22, 2009 7:04 pm

Blue Rabit wrote: So for max mpg from an engine we are leaning towards something built on a 1300?

Not necessarily. Depends mostly on how you drive, but just about any build can be made fuel-efficient.

Thu Oct 22, 2009 7:08 pm

Supposing it was someone without a heavy foot but didnt always remember they were driving for economy.....i.e forgetful me

Thu Oct 22, 2009 7:10 pm

There's no free lunch. To get the best mpg out of any size motor you'll need to do at least a little work.