Will an alternator "shield" alter performance?

[Cardboardcat15]

one of the few problems with 1UZ's. Always known for power steering pump lol. I'm jelly of your car btw.

Aside from that, if I were in your situation I would fix the pump AND fab up a nice shield. I'd contact the H/O company of your choice though and run it by them, that way you can get a professional opinion on whether or not a shield will alter performance at all. Plus, if it does happen to amass a bunch of heat & hinder performance, something like that could possibly void a warranty which is never a good thing. It's far-fetched, but you can never be too safe.

[Renman]

So, I am the guy making the Alternator Shields, and thought that I would offer some insight. I have had this same shield on my 93 SC400 for 3 years now with no issues whatsoever. I have purposely not repaired the power steering pump leak to test the shield long-term. The shield is performing as it should. I have sold about 50 of these shields, and no customer has reported any issues.

Yes, it looks cheap. It is cheap, and it works great! Mounted, it is hardly noticeable since the alternator is mounted low and mostly unseen. I have had a few buyers return the shield when they received it - failed to realize that it is a bleach bottle which it clearly states in the listing. My mechanic even likes it. The shield has plenty of airflow, and the plastic probably shields the alternator from radiant heat (versus metal heat soak), perhaps neutralizing an airflow temperature increase. I live in Hotlanta, GA with tough driving conditions. The pictures are from the first shield that I made, and it is still on my car. I have refined it a little bit.

Sure it's best to fix the leak. But how about some insurance when you don't know when a leak is going to occur? It's interesting that the conventional wisdom is that a shield will cause heat to the alternator, and everyone has an opinion. This seems to be mostly without any direct experience - at least on these cars and under these conditions. If my alternator fails, it will be disassembled and tested for the cause and further evaluated, and the facts will be presented as they are. I think that actual experience and usage of the shield shows that the product works.