It's in good condition and has 120,000 miles, it has good acceleration, performance, etc...
but sometimes I need to accelerate from a stop to 60 up a fair hill, call it 20-30 degrees.
It's got a real problem there. it takes forever to get up that hill, and by the time I get to the top i'm only at about 40. Other cars don't have that problem, they fly on up to 60.
I shift later, around 5000rpm (usually 3500-4000), but I still don't get near enough acceleration. The other cars are already on my tail, or passing me.
I've read around a bit and it appears that I need to get more air into the intake. I took a look and I can see why, There are only two ways for air to get through the air filter: from around the headlight and from behind the engine.
all of the fresh air comes around the headlight through a tube that's only 1.5".
The cheapest method of improving power seems to be improving air flow, so does anyone know a good way to get more air into the box, without busting it up much? or another cheap way to improve engine power would be great!
I found a receipt in the manual dated 2001 where the lady I bought it from had put a new clutch in and resurfaced the flywheel, and done some other transmission work.
I thought i'd check to see how much air was actually being sucked into the air filter box by turning the car on and putting my hands around both holes at the bottom of the box.
I was surprised to find that there was hardly any suction occuring at all.
My dad had an old beetle and he said that he'd put his hand by the carburetor and it practically sucked his hand through.
What about using the rev range more where the car has it's maximum torque? So around 2500-3000 for the 1.8 with 75 or 90 bhp.
But then again 20-30 degrees that is some hill... a 100% incline is 45 degrees (every 100m you travel you gain 100m in height). So 20-30 degrees is a serious slope isn't it?
I was just on an 8% slope (is % grade different then degrees?) on Friday night... it seemed fairly steep (and very long)... I wasn't driving, but we went up IIRC a 12-14% grade in the mountains of Nova Scotia, while towing a trailer (Appalachians probably - Cabot Trail) - There's no way, at least in Canada that you would see 60Mph/100Kph up a 20% hill - there are very few of them, they are very windy, fairly narrow, and the suggested speed is around
25-35kph, less around bends... You take them >> I thought i'd check to see how much air was actually being sucked into
Getting more air into the airbox is simple... you can install a komi scope in the front valence and pipe the air into the air box, or you could swiss cheese your airbox, or install a cold air intake. Ensure that your filter isn't cloged, and maybe upgrade it to a high performance filter. On the extreme end, there is always forced induction.
There's already a "cold air intake" from around the headlight.
There's no need to drill or cut into the box. If you Google, you'll find my instructions for removing the resonator cone from the airbox, and in another article, a description of a simple mechanism to restore full preheat.
Removing the resonator cone increases torque at low engine speeds but doesn't feel like it does much for the top end. Throttle response improves a little. It does increase engine (induction) noise.
Another cheap/free improvement is to slacken the spring on the AFM by 2 or 3 notches. You don't get more maximum power, but throttle response improves at the cost of a small increase in fuel consumption.
Further improvements require work "inside" the engine. These changes can get expensive.
The simplest is a change of camshaft. If you do that, also get an adjustable cam sprocket as most of the sports/fast-road camshafts are shift the driveability compromise to higher engine speeds. The cams can be "tuned" for street use by advancing them by between 2 and 8 degrees. With time and patience, one could advance the camshaft until high-speed performance drops noticeably, or until driveability at the low end becomes worse instead of better.
"High-performance" filter makes no difference on the car in terms of real performance. A washable K&N works out cheaper over the years if you don't have a cheap source of paper filter elements.
It's always a good idea to ensure that the engine is functioning as intended by the manufacturer before making any changes to improve performance.
Check basic timing. That means pull the cam cover and check that the cam is at TDC when the cam sprocket is at TDC and the crank is at TDC. Once that's all done, ensure that the ignition timing is set according to TFM.
Failing to do either of those with an engine that's "mysteriously" short on power is likely to result in nothing more than a headache.
Check for false air leaks and ensure that electrical connections are good.
Replace the fuel filter if it's of unknown age or has more than
60,000 km (or 1000 engine hours) on it.
Use a good synthetic oil. Check tyre pressures (pump them up a little harder than manufacturer's spec - they're at the maximum on the vehicle placard) and wheel alignment.
Once you're happy that the engine isn't going to "explode", do an "Italian tune-up".
Check that BOTH fuel pumps are operating. The transfer pump in the tank is more likely to fail than the main pressure pump. A tell-tale is surges or lack of power driving uphill when the tank level is low.
And speaking of fuel; Digifant engines love the Octane Number. The higher the number, the better. Premium unleaded fuel should be the
*minimum* ever put in the car. Don't bother with expensive octane boosters unless you're spending a day on the track.
Higher octane fuel counts as a cheap performance enhancer.
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