My 1984 Trans AM has 10 ohm speakers in front & 4 ohm in rear.
My grandson just purchased a 1988 Firebird. Are the front speakers still 10 ohm? Rears 4 ohm?
tkx

 

My 91 has 4 ohm all around.

 

My grandson just discovered that the speakers are 4 ohm aftermarket jvc.

 

Factory Delco should have 2 10-OHM in front and 2 10 OHM (Chevy) -OR- 2 4-OHM ( Pontiac ) in back.

DO NOT CONNECT 4 4-OHM SPEAKERS TO A FACTORY RADIO !

Most aftermarket speakers are 4-OHM and most aftermarket radios call for 4 4-OHM speakers.

 

My factory speakers measured 9 ohms front and 3.5 rear...

 

A point to remember about speaker resistance;

When you see "8 ohms" or "4 ohms" those are the speaker's average DC resistance as measured with an ohmmeter (which is using a very small DC voltage to achieve the measurement) This is a test condition only and is presented as a "center point" measurement to properly select a speaker to match the amplifier's output specification. In the real world of listening to the audio produced the speaker isn't being fed DC, if it was the speaker would be destroyed in short order. All audio coming from an amp is an AC signal of varying frequency, whose impedance is measured differently than a simple DC circuit.

John's advice is spot on, use the ohm rated speakers that properly match the amp's rated output, I just figured you all may want to know that there is a bit more to speaker impedance than a simple DC reference measurement. A device working on a variable frequency AC signal will never present a perfect 4 or 8 ohm load to the driving source, as the impedance will vary with the varying frequency of the source audio.

 

Use a 4 ohm against a 8/10 radio's output & bye bye internal amp in the radio.