Spark Plugs and LRR Tires for 8.74% Increase in Fuel Economy

[sal sorrentino]

Here are some links, one to Pulstar, which claims a 4% and 15 horsepower increase in the 1.3 liter Civic Hybrid;

and the other to The Tire Rack test of low rolling resistance tires, with a 4.74% increase utilizing the Michelin Energy saver A/S tire compared with the Goodyear Integrity tires.

http://www.pulstar.com/pdf/whitepaper_hybrids.pdf

Tire Rack tests low rolling resistance tires - News - Modern Tire Dealer

[Purplegate]

This is interesting !

But for the spark plug, they have no choice in the drop down menu for the Insight. I sent a mail to ask... Anybody know if these spark plugs would be an issue (waranty...) for Honda ?

For the tires, they never offer a comparison test +% compare to what. It would be interesting to see a comparison between the Michelin Energy Saver and some of the OEM tires on the I2 (mine has Dunlop SP31, but I think there is few other tires depending where the car is sold). But it's surely to be consider when tire will be due for replacement !

[adric22]

I hate to always be the skeptic.. But if the spark plugs really made that much difference, Honda would put them (or something like them) in the car from the factory because it would improve the car's rated fuel economy, as well as their entire CAFE.

[JimJohnD]

I'd have to go with adric22 on this one. If we were talking about my '72 Dodge 360ci, sure, the type of plugs I used did make a difference. As far as 'more' spark, Honda already looked at that. The Insight has 2 spark plugs with their own coils for each cylinder. The plugs are spun in so that the electrode faces the right way for the best combustion. If the plugs had the same physical specs as the stock plugs they shouldn't 'hurt' anything. Still, with all of the performance monitoring I doubt there is much improvement to be had. Without a dyno it would be really difficult to find the difference from all of the other factors in play from air temp to tire pressure. If you do give them a try please let us know what you think of them.

[coinsight]

Anyone who thinks they are going to see measurable HP and mileage gains from a spark plug is clearly an idiot. On *some* very high compression, high performance engines operating at very high rpm, there is a minuscule hypothetical gain to be had from aiming the plug gap at the intake valves. On a hybrid? No way. The spark plug has one job, and that is to ignite the incoming air/fuel mixture. Modern ignitions run at 40-80,000 VDC. The spark blowing out is the least of your worries, unless your plugs are corroded or you have faulty wires.

However, I have some SuperSnake(tm) Oil that when only one ounce is added to the crankcase, results in amazing mileage and horsepower gains. I'm working on a website/blog/email blast to get the word out.

[magus_melchior]

Originally Posted by coinsight

However, I have some SuperSnake(tm) Oil that when only one ounce is added to the crankcase, results in amazing mileage and horsepower gains. I'm working on a website/blog/email blast to get the word out.

I'm told it's fantastic for fish & chips, too.

[sal sorrentino]

Have you read the White Paper link? It was put on a dyno and fuel useage measured with a fuel meter.

The plugs are expensive and as Honda has stated they were looking to minimize cost on this Hybrid, there may not have been a budget for eight plugs that add to the production cost.

Is the tire test a fallacy as well? Would Honda certainly have put the Michelins on if they wanted better mileage?

[Purplegate]

Anyway, received the reply from the company :

Thank you for your inquiry.

Unfortunately, our plugs are not suitable for the Honda Insights. The coils on the Insight have a smaller plastic boot than most that do not fit over the terminal end of our plugs. I apologize for any inconvenience.


Seems we will not see it on the I2 !

[jraynor196]

Originally Posted by sal sorrentino

Is the tire test a fallacy as well? Would Honda certainly have put the Michelins on if they wanted better mileage?

I think the tire test is valid. 2 to 4 percent increase is believable.

But, you can pump up the existing tires from the recommended 33#s of pressure to around 40#s of pressure and get the same increase.

Not sure about the OEM tire selection. Could be a cost factor.

[Cobb]

Tires alone inflated to the max psi on the sidewall can give at least 10% increase.

Plugs do make differences, but its a ratio. I used tri electode plugs a few degrees cooler for my blown tacoma and man, it made a world of difference.

I went with the +4 bosch for my scion and it made a slight seat of pants improvement, it was a 1.5l 100hp