[sapsz28]

Hi guys what exactly makes for a good street hei wire ,I'm confused about all this talk about ohms and resistance ,is a lower number better 500vs250vs80 I'm really confused,its a1980 Z28 streetdriven sbc mild everything any help would be greatly appreciated thanks.

[78 monte]

If you mean plug wires you need spiral core for the street.Solid core will make your radio screw up.
If its a mild build I wouldn't put to much thought or money into plug wires a new set of cheap-o sorensen 8mm wires is as good as any 8mm IMO. Any more than 8mm is kinna over kill especialy if your running a stock coil.

If your talking about the 12V feed to the hei GM use4s a 12ga. wire to feed there coils.

[Notorious]

I've had MSD wires on the Vette for at least 35K miles now with no problems. It still had stock manifolds on it when I first installed them. Since then it's on it's third different kind of headers. (I'm always changing things around ) Close is of no concern with these as long as actual contact with pipes is not made. They're a little more expensive than some but an excellent long-term investment. I've never had to replace a boot or wire yet.

[302 Z28]

Taylor is the best in my Book. Their spark plug ends are the absolute best in the market.

Vince

[sapsz28]

Thanks for the input to you all its great to be part of this great hobby

[curtis73]

I'll second the Taylor recommendation.

As far as size is concerned, the only difference is insulation. The conductors aren't any better, its just that an 8mm wire has an extra millimeter of insulation on it. On a stock system, 7mm is more than enough

Spiral core is great, solid core not only will mess with your radio, it can fry a stock coil. Some manufacturers won't honor a warranty if you use solid core wires. They're best kept for race only.

[Notorious]

Originally Posted by curtis73

I'll second the Taylor recommendation.

As far as size is concerned, the only difference is insulation. The conductors aren't any better, its just that an 8mm wire has an extra millimeter of insulation on it. On a stock system, 7mm is more than enough

Taylors are good too. But regarding insulation, many cars use 8mm from the factory. Surely in those cases you wouldn't want to use less.
Also, regarding resistance, (or the lack thereof) MSDs are among the best out there.

[58Apache]

To answer your general question, in general, less resistance is better.

Resistance to the flow of electricity (current) is measured in the unit named Ohms. There are mathematical formulas that use the amount of ohms to determine how much current will flow, for a given amount of voltage.

The coil will put out about 40,000 to 50,000 volts, in order to jump the gap in the spark plug. It sends this voltage down the spark plug wires, so you want as little resistance as possible, and a great insulation so the spark won't jump off before it gets to the spark plug.

The coiling of the conductor (wire) inside the plug wire sets up a magnetic field that opposes the change in current. It will add more "resistance" as you send a current into it from that magnetic field, and as the current falls off, it will send energy it has "stored" in a magnetic field down the wire which will try to smooth things out a little.


The pulse sent to the spark plugs causes radio interference. They used to try to reduce this by adding a spark plug with resistance in it ...so if you ever see a spark plug number that begins with R it means it's a resistor plug.

If you can solve your radio problems with the coiled conductor spark plug wires, don't use a resistor plug. It doesn't make sense to pay extra for less resistance wires and use a resistor plugs.

Steve

[Irelands child]

Taylor Spiral Cores work great and I have been assured by others that the MSD Spiral Cores are good as well (probably made in the same factory by Taylor but with the MSD logo). I usually buy the Taylor 'universal' set and make up the lengths according to how I want them to run rather then someone else deciding for me.

These Taylor's are on a SB Ford:

[jimfulco]

I've used Borg/Warner spiral-core wires on a few cars, and they seem to work fine. Pep Boys sells them for ~$35, but they had to order them last time. They come in a beautiful shade of OEM gray and black, if you're into stealth.

[GMCTRUCKS]

MSD you can't go wrong im MSD all the way.

[302 Z28]

Originally Posted by GMCTRUCKS

MSD you can't go wrong im MSD all the way.

Just don't get the MSD 8.5mm wires, I could not find any wire holders to fit them that I liked. Sold them and bought a set of Taylor wires...could not be more pleased.

Vince

[red65mustang]

reality check?
the coil will charge to a voltage level high enough to jump the sum-total resistance of the dist rotor gap (gazzillion ohms) plus the (minor) wire resistance plus the plug gap(gazzillion ohms) and the A/F resistance and pressure in the chamber (gazzillion ohms)....on a typical mild 350 with HEI and a plug gap of .045 that is roughly 15,000V (not 40,000).....

anything around 1,000 ohms per ft is fine....basically over the counter Borg Warner or Bosch ($35) or NAPA or any other quality brand spiral wounds.....

"if" your gona mess with the plugs alot.....then boot construction is a priority...and Taylors are well made....

"if" one set is a little more ohms per foot...it will force the coil to build to a slightly higher V (maybe 16,000V?) before it can jump the gap and that can burn a slightly bigger initial hole thru the mix to make a bigger flame kernel.....(ex: old weak points systems were 2,000 ohms per ft to try to "boost" coil output at a .032 plug gap)

"if" you add a msd 6al CD ign box or similar....then you need less resistance and more insulation for emf/rfi due to the extremely high voltage......

note that most of the new cars have gone back to carbon wires of atleast 3,000 ohms per ft....(to protect the ecu and SS devices)....and many are down to 5-6 mm insulation handing much higher spark V with even bigger gaps.....