Do Heat Shields Really Work?

[packick]

I don't know if this topic has come up before, but I was wondering if those metal heat shields that bolt top of the fuel pumps on our vintage cars really work?  Or are they a gimmick?  I have heard arguments both ways.  Some say they work, and others say they trap the hot air and prevent air flow circulation that's required to keep the fuel pump cool.  And still others say they do nothing at all.

 

Any opinions?  For the sake of argument, let's assume we are using non-ethanol fuel.

Edited August 15, 2016 by packick (see edit history)

[Mark Shaw]

Factory heat shields do work for specific applications; otherwise, manufacturers would not include them in their cars.  Aftermarket products work sometimes; depending on the application and expectations of the user.  The best way I know to keep fuel cool in the engine compartment is to install a bypass at the carb. so fuel does not sit in the hot area waiting to be used.  Constant replenishing with cool fuel from the tank will prevent vapor lock in most cases. 

Edited August 15, 2016 by Mark Shaw (see edit history)

[smithbrother]

On a couple of my cars I have starter heat soak not from non-cast iron headers, but STEEL tube headers.  I made heat deflectors, and had good results, I installed them so there was distance between the starter and the header, and so air could flow between both.

 

Yes designed and installed correct they can/do work, IMHO

 

Dale in Indy

[raydurr]

Heat shields should deflect or absorb radiant heat only.Heat transfer from block or contact with other components will occur with or without heat shields. A gap for air flow between the shield and the subject part should be maintained.

[FLYER15015]

On ‎8‎/‎15‎/‎2016 at 9:21 AM, Mark Shaw said:

Factory heat shields do work for specific applications; otherwise, manufacturers would not include them in their cars.  Aftermarket products work sometimes; depending on the application and expectations of the user.  The best way I know to keep fuel cool in the engine compartment is to install a bypass at the carb. so fuel does not sit in the hot area waiting to be used.  Constant replenishing with cool fuel from the tank will prevent vapor lock in most cases. 

OR, you could coil about 6' of copper tube in a coffee can between the pump and carby (for our down under friends) and drop in some dry ice, like our racer friends used to do. Makes for lots of stops to reload though.