Fiberglass Hoods and RFI

**65 Fastback** · 01-03-2008, 08:24 PM

I was watching the Barrett-Jackson auctions the other day, and they mentioned that a 1970 Cuda had a factory fiberglass hood. The antenna had to be moved to the rear since the car no longer had a metal hood to block RFI's.
Is this true on modern day cars as well that have aftermarket fiberglass hoods? I have never heard of this before.

**Ares** · 01-03-2008, 11:05 PM

Most newer mustangs up to '04 use fiberglass hoods. They do also have a grounding strip from hood to body.

**65 Fastback** · 01-04-2008, 08:49 AM

Originally Posted by Ares

Most newer mustangs up to '04 use fiberglass hoods. They do also have a grounding strip from hood to body.

Does this mean that if I put a 'glass hood on my '87, I should ground the hood? Wouldn't the metal hinges ground it to the body?

**mikeymustang** · 01-04-2008, 10:54 AM

I am an RF tech by trade...

In the 70's when the Cuda came out most cars came with AM radios. AM is very prone to ignition noise. When you cover the engine/ignition with a METAL hood and ground it it shields the noise from getting into the radio. We all use FM ( not prone to noise for several reasons)... one being MUCH higher in frequency.

Any other questions?

Mike

if you want to try an experiment...take a cell phone stick it into a grounded metal mail box and close the lid...it probably won't work unless your very close to a cell site

**65 Fastback** · 01-04-2008, 11:57 AM

Originally Posted by mikeymustang

I am an RF tech by trade...

In the 70's when the Cuda came out most cars came with AM radios. AM is very prone to ignition noise. When you cover the engine/ignition with a METAL hood and ground it it shields the noise from getting into the radio. We all use FM ( not prone to noise for several reasons)... one being MUCH higher in frequency.

Any other questions?

Mike

if you want to try an experiment...take a cell phone stick it into a grounded metal mail box and close the lid...it probably won't work unless your very close to a cell site

Thanks Mike, I never thought about the AM versus FM feature. I was just curious about this whole idea. John