Premium Fuel Hack

[Cobb]

Either making the plug cooler or reducing the CR by removing material from the combustion chamber will allow cheaper or lower octane fuel. Another idea is to use spark plug spacers or washers. This way you can further your efficiency by indexing the plug in relation to the valve locations.

Sometimes you can get a better quality fuel and get the same octane rating with better performance. The gen2 insight likes shell or bp fuel better than the discount fuel.

[elhigh]

The farce is strong in this one.

Sorry dude, not going for it, not even on the truck. Even though its engine is just slightly more sophisticated than the Farmall's...and I am not going to try it on the tractor, either.

[Mustang Dave]

Originally Posted by elhigh

The farce is strong in this one.

Couldn't've said it better myself.

[iveyjh]

Originally Posted by Cobb

Either making the plug cooler or reducing the CR by removing material from the combustion chamber will allow cheaper or lower octane fuel. Another idea is to use spark plug spacers or washers. This way you can further your efficiency by indexing the plug in relation to the valve locations.

Sometimes you can get a better quality fuel and get the same octane rating with better performance. The gen2 insight likes shell or bp fuel better than the discount fuel.

Spark plug non foulers will lower the cr without cutting anything.

[Frank Lee]

Personally I'm not real interested in trying it. I have a supercharged vehicle that is supposed to have premium but I've had no problems running it on ethanol blends (ethanol LOVES compression, static or forced). If it did have any issues I'd simply run a stronger ethanol blend or next, try the next colder heat range plugs.

I'd also be nervous if trying this with aluminum heads as the threads in the head are fragile enough the way it is; I'd use less than the recommended torque on modded plugs as these and be darned careful the plug's threads don't damage the head's threads due to any "hangnails". Also it may be prudent to simply R&R modded plugs more often because there is going to be an exposed section of plug hole threads that may carbon up or otherwise want to trap the plug in.

In spite of the minor cc increase and corresponding minor C.R. drop, this mod exposes sharp edges to the chamber that wouldn't be there otherwise; seems to me that could increase detonation. And I wonder if such a recessed pocket is a hindrance to good combustion chamber geometry- like the old-time engines that had pre-chambers. Pre-chambers are all but extinct now.

Or maybe I'm just over-thinking it all.

[Xist]

I drive an economy car, which burns economy fuel. Interesting responses, though.

[rmay635703]

If the mod caused detonation one would only need to watch one of the many engine monitoring devices to see if timing pulls back.

Also (not saying this is a good idea either) but with a decent machinist one could leave a "sleave" to cover the thread end of the plug, the volume reduction would be less but then it would just blow the sleeve up before the threaded hole. (hollow plug)

Its his car and his money, if it works for him more power to him, would be interesting to see what happens in 100,000 miles (if anything)

I have a feeling this mod could cause more irritation than stock but likely little else.

Helicoils might happen though.

Good Luck
Ryan

[Cobb]

Tell me about it. Several eco cars run high compression and either run retarded timing or require premium fuel. At that some stations top out at 91 vs 93 octane fuel.

My insight drives better with the better stuff, so Ive thought about getting a head job and uppering the cr and run 93 all the time.

Originally Posted by Xist

I drive an economy car, which burns economy fuel. Interesting responses, though.

[BikerModder]

A Denso 5353 Spark Plug is for Smart what it came with. They would have put in their lawn mower if it were up to them.

Mileage is maybe 1 mpg off now that the car runs on 87 but it is strong. I still use syn oil took the old paper filter out and get 49 hwy 87

Leather seats are in the works. I put size larger Goodyear tires (85 175 R15) For the rear and 55 165 R15 on the front. on put I have to find the thread for that here next.

I won't use Premium for the efficiency does not help save gas or money. I tried it last week and at least from my stand point there would be no reason.
And while I feel like I do less I maybe doing more by the type car I drive in saving money. Reliability seems to be a thing too. This car does have a timing chain. But yeah I can only receive calls and stuff on my day off. Premium!

[Cobb]

Thats right, its made my mercedes right? I thought it was neat, but after visiting the checkered flag smart dealer I was turned off. I was told no trade ins, and only test drives for serious customers. It wasnt like they were busy that day either. I looked at the regular and convertible model. It had some room for a big n tall guy.