Anyone done this mod before? http://www.sunautomobile.com/ Looks like a cheap way to add 5hp, but I'm not sure I believe them. Please let me know your opinions. Thanks!

Well, good grounding is always a good idea, but I don't know if I'd pay $100 for it. You can accomplish the same thing with large gauge wire (2AWG?), large crimps and a bit of time...IMHO. Although, I don't know if you could get the designer colours...

As for the hp increase, seeing that the sparkplug grounds to the block, then theoretically, having the block well grounded will (should) produce a better stronger spark.

My $0.02 FWIW.....John

Can anyone define "good ground"? I tested my positive post to the frame and had an ohm reading of just less than 2 ohms. Is that good? Thanks!

In theory, a good ground should have 0 ohms. I measured mine with a Fluke 73mkII DMM to have 0.2 ohms

I don't know at what point an auto ground in "not good" (could be 2 ohms, could be 20 ohms), but it's best to shoot for the lowest possible resistance/impedance.

IMHO, YMMV, etc etcJohn

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