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banzairx7
12th September, 2018, 01:44 AM
Hi all,

I have a Smart 451 1.0 non-turbo US spec that I would really like to tune. Best case scenario I'd be able to get software and do it myself. I'm very familiar with tuning. DOne a ton of Megasquirt set ups, HP tuners for GM etc. I can't seem to find anything that is less than thousands of dollars that might be able to tune it. Any advice on where to look/buy would be greatly appreciated.

If that isn't an option I would gladly use a shop that can actually tune the car. All the places in the US don't list any specifics on what they change, dyno runs or any customizing to your needs. Some one who could take a datalog and adjust the fuel/timing based on that would be fantastic.

Any help is much appreciated!

oldford
12th September, 2018, 06:43 AM
So what's your goal? Gain 1 or 2 horsepower? It will always be a 1.0 liter non-turbo engine.
The reason that nobody shows dyno graphs is probably that stock and tuned are very similar if not the same for this engine.
The only real gain in horsepower you will get if you add a turbo, but that will be costly.

banzairx7
12th September, 2018, 01:08 PM
There's probably more than 1-2 or two hp in the stock car. I've done some datalogging and the timing and fuel maps are very conservative. I'd also like to try various mods and be able to tune for them. The exhaust manifold is terrible. An equal length unit would definitely add some power. Also the throttle body and intake manifold are very much sized for low end torque and not ultimate power.




So what's your goal? Gain 1 or 2 horsepower? It will always be a 1.0 liter non-turbo engine.
The reason that nobody shows dyno graphs is probably that stock and tuned are very similar if not the same for this engine.
The only real gain in horsepower you will get if you add a turbo, but that will be costly.

oldford
12th September, 2018, 03:25 PM
The exhaust manifold is terrible. An equal length unit would definitely add some power.
I remember a test performed by the magazine Cars and Cars Conversions. They tested 20 so called spaghetti exhaust manifolds on 1 car.
18 of them produced LESS power, 1 was equal to the original and ONLY 1 gained a few horsepower.

In my own job I have experienced somewhat the same with Porsches.
A couple of friends had ordered expensive (several thousands of dollars) exhaust systems with exhaust manifolds in the USA.
I was interested in selling these parts, so I said I'll do the dyno run before and after for free.
I quickly lost interest in the product when the after run showed a loss of 10 horsepower.

Another occasion was in tuning a 944 engine that had standard 170 horsepower.
Under the rules the car was racing 200 was allowed. So, we rebuild the engine with a mild camshaft that would give some 20 - 25 horsepower extra.
After the engine was run-in, I started mapping the car but I couldn't get more power then 170, whatever I tried.
I then saw the non-standard spaghetti exhaust manifold and decided to change it for the stock exhaust manifold.
30 minutes later the engine test bench showed a healthy 205 brake horse power.

So, I am not so sure that a different exhaust manifold is going to give you extra horse power.
A other throttle body might give some horsepower, but it's still a 1.0 non-turbo engine. So, don't expect 20 horse power extra.

As to changing the maps based on a datalog, I wouldn't do it for any price. You can't predict when knocking is going to happen.
And the standard Oxygen sensors are narrow band. So, at least for the logging you must add info from a wideband oxygen sensor.
For that reason the car must be on a rolling road or the engine must go on a engine test bench after each mechanical change.
And that is going to make it expensive for just a handfull of horse power.

The 1.0 non-turbo engine delivers 70 bhp - now I don't call that conservative. I bet you will struggle to find anything extra.
The Brabus turbo 1.0 engine delivers a healthy 101 bhp. 100 bhp per liter for a turbo charged engine is what I call conservative.

N.B.: I first assumed you just wanted the ecu mapped, that's why I quoted the 1 or 2 horse power gain.
You never mentioned mechanical changes.