[Jim-Bob]

Originally Posted by fairdinkumfrankies

I love all of these ideas. Lots to consider. It is going to take awhile to sort out which to do. The $10 air dam sounds good but the spoiler concept sounds great. Keeping budget in mind, I will go cheap first and move on from there. Drifting between the links from this site I have seen higher compression, steel valved heads being recommended. I was wondering if the eco minded folks would think that was a good idea and if so, at what point do you have to put in higher grade fuel? I think it said 9:1 and 10:1 or something like that. I know my 89 Swift GTI had a pretty high compression ratio but was running 86 octane with no issues.

The light wheels sound good to and I am now not leaning towards the skinny tyres. The rolling resistance article was informative. Now I am thinking 165/65 14 on a set of light wheels. The new rig is going to need snows so I will buy those for the steel OEM wheels in the 155/80 13 size.


I also liked the CAI idea. Would a heating pad for the block help here in the Northeast?

Thanks,

Neal

Stainless steel exhaust valves are ALWAYS a good idea-especially on the G10. The higher compression ratio will help with low RPM torque and mean you do not have to push the engine as hard to get the same acceleration. The same holds true for the Metro XFI camshaft or 3 Tech's economy cam. Both raise low RPM cylinder pressure which smooths out the idle and decreases throttle input under normal operating conditions.

As for tires, you could also consider 175 70 13's on your stock rims if you want to try the wider is better idea. They cost about the same as the 155 80 13's and would give you the extra width inexpensively. This is another idea I plan to try on one of my Metros but more for better handling and braking than for fuel economy. No matter what that study says, I have seen the opposite to be true on my truck. 235 60 15's dropped me 1-2 mpg vs the stock 215 65 15. It may well be that the whole reason that the rolling resistance decreases with width is that the load is spread too thinly on narrower tires and going wider in certain circumstances reduces the load. Once you get past that point though it would make it worse. Also, if that is the case, then it stands to reason that wider tires on the front to better support the engine and trans would have the most benefit and the rears should therefore be narrower. However, this is all just speculation on my part as I am struggling to find a logical and mathematical explanation of the data set.