Discussion
Drove my dad's new Mk.2 1.8 the other day, very interesting to compare with my Mk.1 1.8 S-Spec.
To begin with it is a much smoother ride - probably down to the S-Spec Bilsteins on mine, but his feels like it is more compliant, less crashy, and probably better suited to UK roads.
The big difference was acceleration though. Now, neither car sets the world on fire, but the Mk.2 is a lot quicker off the mark. By 50mph it's all done in either car, but the Mk.2 feels a lot more lively.
Now, I know the Mk.2 has VVT, but the timing has just been checked and reset in my Mk.1 (14o BTDC) and it made no difference that I can see.
Is this normal? Anything I can check? I have already used injector cleaner. New HT leads fitted. It has an old cone air filter which I'm going to swap out for a panel one in case it's suffering heat soak.
To begin with it is a much smoother ride - probably down to the S-Spec Bilsteins on mine, but his feels like it is more compliant, less crashy, and probably better suited to UK roads.
The big difference was acceleration though. Now, neither car sets the world on fire, but the Mk.2 is a lot quicker off the mark. By 50mph it's all done in either car, but the Mk.2 feels a lot more lively.
Now, I know the Mk.2 has VVT, but the timing has just been checked and reset in my Mk.1 (14o BTDC) and it made no difference that I can see.
Is this normal? Anything I can check? I have already used injector cleaner. New HT leads fitted. It has an old cone air filter which I'm going to swap out for a panel one in case it's suffering heat soak.
Is your dads car a Mk2 or mk2.5 (i.e. is it pre or post 2001)? If it's pre 2001 then it will have VICS but not VVT.
Mk1 1.8 is around 130bhp (range from 128 to 133 depending on year/market).
Mk2 1.8 is 138bhp.
Mk2.5 1.8 is 146bhp.
However! The Mk2.5 is a bit heavier than the Mk2 which is in turn a bit heavier than the Mk1.
Regardless of this, each new mk will be slightly quicker than the previous one. The difference should be fairly small though.
I'm surprised that you say it's all over by 50mph in either car though. Both should be able to reach almost 60mph in 2nd (assuming they are both 5-speed) and 3rd should still pull fairly well.
I wouldn't worry about your air-filter. It won't have much effect on power good or bad. Even a bit of heat-soak won't make a lot of difference on a normally aspirated car.
Mk1 1.8 is around 130bhp (range from 128 to 133 depending on year/market).
Mk2 1.8 is 138bhp.
Mk2.5 1.8 is 146bhp.
However! The Mk2.5 is a bit heavier than the Mk2 which is in turn a bit heavier than the Mk1.
Regardless of this, each new mk will be slightly quicker than the previous one. The difference should be fairly small though.
I'm surprised that you say it's all over by 50mph in either car though. Both should be able to reach almost 60mph in 2nd (assuming they are both 5-speed) and 3rd should still pull fairly well.
I wouldn't worry about your air-filter. It won't have much effect on power good or bad. Even a bit of heat-soak won't make a lot of difference on a normally aspirated car.
In that case it won't have VVT, just VICS (variable intake length - some clever tuning in the intake to improve mid-range torque).
however, you can forget mid-range in any normally aspirated MX-5. They don't really come to life until after 4krpm and need thrashing to the red-line to make real progress. Luckily they have a fantastic gear-change so dropping down a gear or two isn't really a hardship. The VICS in the Mk2 and the VVT in the Mk2.5 both add mid-range torque but thrashing from a standstill to the redline through the gears there should be little difference between them all.
Even my 1.8 Zetec Focus is quicker at low/mid range than a stock 1.8 MX-5 but if you thrash it the Focus won't see where the MX-5 went.
however, you can forget mid-range in any normally aspirated MX-5. They don't really come to life until after 4krpm and need thrashing to the red-line to make real progress. Luckily they have a fantastic gear-change so dropping down a gear or two isn't really a hardship. The VICS in the Mk2 and the VVT in the Mk2.5 both add mid-range torque but thrashing from a standstill to the redline through the gears there should be little difference between them all.
Even my 1.8 Zetec Focus is quicker at low/mid range than a stock 1.8 MX-5 but if you thrash it the Focus won't see where the MX-5 went.
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