Hi. Just started using my newly acquired '95, 1.8 NA and am emjoying it a lot. But…I would like it to be a bit livelier. If it was a person, it would be in a monday morning mood all the time…bit knackered after a hard weekend and wants to go back to bed. Unless I thrash it of course, but it’s not practical to keep the revs up at 4500 plus all the time. How do I get a bit of low down grunt?
In other words, what are the usual and most obvious first steps, and the cheapest and easiest, to improving performance? I don’t want to go to town on it. One day, cash permitting, I might look at turbo charging, but not yet. I’m a bit of a purist and like to keep things as near to spec as possible. But my last car was a Lotus Elan M100 that went from 0-60 in about minus three seconds, and I’m missing the buzz.
I believe you can do the ‘exhintake’ mod on the 1.8’s
Swap the inlet cam for an exhaust cam, and bump the timing up to 14 degrees
Should make it a (tiny) little bit livelier! Maybe 5bhp and lower torque band
Thats the limit of my knowledge for the 1.8 as I have a 1.6
Er, just thrash it . Thats what you do to em.
Welcome to the frenetic hi-revving world of 5-ing. Bottom line is, you ain’t got torque…none! Good news is…you ain’t supposed to have any!. Keep it well oiled, ensure plugs, leads, breathing and cooling system are tip top, think 60’s Twin Cam Cortina/ Elan and rev it’s nuts off. It’ll love you for it! You cannot abuse it really…they are “over engineered”
Ha. As a matter of fact I’ve just been out for a blast and I’m starting to get the hang of it. Great fun.
But…I did need to overtake someone who was doing 50, and it took ages. It’s that mid range pull that’s missing. When you’re doing about 55 and you want to accelerate hard…there isn’t quite the space for downshifting, and yet overtaking the grannie took ages.
However, I don’t mean to complain. I had loads of great fun tis evening. It does need a bit of thrashing though…can’t do much for the fuel consumption!
I used to have an MX6. That was a lovely car. Oodles of torque, balanced and smooth. Seriously under rated. Perhaps I’ll get another to sit alongside the 5.
Incidentally, what’s the best oil?
And is it worth getting a K&N induction system?
Save your money and supercharge it if you want low down pull
The 1.8 benefits most by bumping the timing to 16-18 degrees BTDC, but you will need to run the car on super unleaded, to avoid pinking. For 14 degrees, you still need to wring the engine a bit.
Fitting any cone filter will gain you a few extra hp at the top end, but you might end up losing mid-range torque, through loss of the primary resonance chambers; the ARC cross-over pipes from Japan are supposed to “restore” this lost torque, though the 1.6 version seems to work better than the 1.8.
You can see some 1.8 timing curves in Norman Garrett’s Miata Performance Handbook (now out of print, but still an excellent and knowledgeable read):
That’s interesting…about the loss of torque with a cone filter. I didn’t really want to go as far as supercharging if I could help it though. Although I’ll look into it more.
To be honest, I think I just need to apreciate what’s there for what it is. It’s a rorty little sports car. Not especially fast but then a car doesn’t have to be fast to be fun. And it’s fast enough. I’ve been spoiled with 2.5 litre V6s and turbo chargers. Mind you, the 1968 1750cc alfa spider I was driving recently was neither of those and, I have to admit, was even more fun than the MX. But hell, it costs a lot more too!
I’ll take a look at supercharging, when I have some cash. In the meantime, I’m really enjoying the car.