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4500 is nothing for even a well built stock 1275, A-series motors were born to twist, If I can make them live at 9000 on track, you can do 6000 all day on the street with a stock motor. Oh and I built those carbs to be richer on the top end, so let her eat /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
IMHO

I agree with Hap (once again). Let em breath, eat, exhaust, vent and done properly they will twist all day long.

80+ flywheel hp for a street BE is alot of fun /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

And that is not very hard to get from a 1275. My choice is a ribcase with a 3.9, ya gotta have that nice whine out of first. "whhhaaaa whaaa whaa"

Drew, it sounds like you are building my BE /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

Hap please swap out that lazy intake manifold for Drew and Drew get that flywheel shave down a little bit.

Pat
 
Thanks, Hap. This reinforces the point I've been trying to make. Spin 'em up! /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
Jeff
 
Doesn't keeping them at high rpms make them suck down the fuel though. My thought was that I could use the lower gears for high rpms and then on the highway kick on up to 5th and with the 3.55 it should settle down nicely. If I want power and high rpms, I can always drive it in 3rd, I reckon.
 
Pat -- Tunebug will be very similar to your Bugeye methinks. I'm content with my choices, now I just have to be patient while Hap performs his magic on my engine. It's going to be a fun spring in Utah, that's for sure! /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
regularman said:
Doesn't keeping them at high rpms make them suck down the fuel though.
Click to expand...

Yeah, it sure does. I only average 32 MPG with the 1098 in the California mountains, and the 1275 gets a miserable 29 MPG here in the flatlands of Michigan. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff
 
[/quote]Yeah, it sure does. I only average 32 MPG with the 1098 in the California mountains, and the 1275 gets a miserable 29 MPG here in the flatlands of Michigan. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff[/quote]

I know you are being sarcastic, but 32mpg for an 1100cc engine is nothing to brag about. Any modern engine of this capacity will best that by 50% under the same circumstances. 30 mpg will not seem so good when gas prices get up around $7.00 a gallon like in Europe today. The Smarts supposedly get 50+ mpg on a 1 liter turbo 3-cyl, and I know they will cruise all day @ 70. The Roadster looks to be as much fun as any Spridget too.
 
The Smart cars get a lot better than that with the diesel, which we <u>won't</u> be getting here in the States.
I don't think fuel economy is the driving issue for owning a LBC. At least it isn't for me.
Sure, a "modern" 1 liter engine will beat 32 MPG. When are you dropping the Smart engine in the XI clone?
Jeff
 
Regardless which rpm the engine runs, it has to produce the same energy to go the same speed. The differences come in the efficiency of the engine at different speeds. A "mussel shell graph" shows maximum efficiency at around 3000 rpm and wide open throttle (wot). However that isn't the major factor in fuel efficiency. The major factors are thermal, friction and wind losses. Face it. 35% of the energy the fuel supplies blows out the exhaust just in the temperature rise from inlet air. Add to that all the pumping losses, internal friction, thremal loss in the radiator, incomplete combustion etc and that's why the Smart car gets such good economy. It's made for it. The A-series isn't.

Here is a torque curve from a pretty much standard 1100 plotted with wind and other resistance for the car. X axis is mph, Y axis is newtons of thrust at the rear wheels, and drag. The four curves are with different differentials. The 4.55 is at the top and as you can see, has a lower top speed, but more available thrust when driving.

FOURDIFF.jpg
 
Bugeye58 said:
The Smart cars get a lot better than that with the diesel, which we <u>won't</u> be getting here in the States.
I don't think fuel economy is the driving issue for owning a LBC. At least it isn't for me.
Sure, a "modern" 1 liter engine will beat 32 MPG. When are you dropping the Smart engine in the XI clone?
Jeff
Click to expand...

LOL, funny you should ask that: I just took delivery of a full-zoot APT 1380 A-series. I told them that I wanted 100hp on regular 87 octane gas with good driveability and based upon the chassis dyno numbers that's what they gave me(torque is over 80 ftlbs from the low 3k's to the mid 6k's). I can go into details if there is any interest, they just got their new dyno on line and mine was the 1st through.

If I was looking for a more modern engine for the XI I would have to take a long hard look at the 3 cyl Suzuki used in the GEO Metro, I believe the Samurai 5-speed will bolt on to make the conversion from transverse installation to traditional fore & aft layout. The problem with most OHC engines esp. bike engines, is that they are too tall to fit under the Costin bodywork.

I have put my money on the A-series, but that does not mean that I am blind to the current state of the art in small auto engines.
 
I'm not blind to current technology either, but prefer originality when it comes to my British stuff. At least in respect to the correct engine <u>family</u>! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
That 1380 sounds interesting, pulling power like that from 87 Octane.
I haven't gone the 1380 route yet, but have an in-line A+ long block that will probably wind up that way. I've a Bugeye in Northern California that would benefit from the change. I've tried to hold my CR's below 10.5:1 so I can run 93, but even then sometimes they aren't happy with that octane.
Have fun with the Westfield. That thing shoulld really scoot. /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
Jeff
 
I used to get 30mpg back and forth to work and around 37 on the highway with the 3.90 gear and the motor was wound up quite a bit. I'm hoping to lower the rpms and do a bit better on gas as well as a quieter ride on the highways.
 
I've noticed that many don't ever get you the true milage when this question is asked. I've many times told all about my driving techneques. Before the latest tune, I was getting 26 mpg. Dissappointed, kinda, but the car is a blast to drive.
 
The A series is possible of giving some pretty good mileage. I had some minis that got around 50 on the highway when I lived in the UK, so a midget having a lower profile should do good too if geared right. At least that was my thinking. Yeah the Austin minis were FWD but still the weight difference cannot be that much.
 
A 3.9 and a strong 1275 in a bugeye should get you 0-60 in 10 seconds. ...but I'm just guessing.

When I had a 1275 and a 3.9 in my midget, I did need to wind it out to the redline more frequently (than my daily driver) to get into traffic. However, that is part of the fun of driving these cars.
 
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