Kappi2907

...are these really bad?

Steve Weiner-Rennsport Systems

Yessir,...they certainly are. Unfortunately, there are cases where there is no good alternative.

Vandit

I installed some and so far so good, but you guys make me doubtful, so periodically I'll make sure the car runs with either ignition module disconnected (i.e. isolate each distributor).

Super90 and others have share their conversion to 993 coils. I'll go that route should I ever encounter an issue with my silver coils.

deadendd9009

These silver coils are the reason 993 upgrade has become a popular modification. Smaller, lighter and more reliable.

Goughary

Agreed. I went through three sets of coils in just a few years. We did the 993 coil conversion to most of our cars. And all are so far happy. I’ll need another few years to determine if they are really that much more reliable, but you don’t see a lot of coil issues w the 993 guys, so i am optimistic

Super90

I have the 993 coils in hand and other bits, but have not yet installed. Every knowledgeable 3.6 mechanic I have spoken with says the 993 coils are better, not only better than the current 964 replacements, but even better than the originals.

A few write-ups included, where the coils were put back in the 964 location. Others have mounted them on the engine carrier like the 993 does. As I recall, based on a phone conversation, that is Steve Weiner's preference as it provides more airflow around the coils to help keep them cool.

Still have not decided which route I will go.

Also, the 993 coils are Bosch part #0221502460 which is both coils. I bought them off Amazon for maybe $130.

https://rennlist.com/forums/964-foru...nto-964-a.html
https://rennlist.com/forums/964-foru...-to-964-a.html

Kappi2907

Any one used the silver ones with No issues?

Peteinjp

I hope so because I Just shelled out for two of them!

Pete

John McM

I’ve just done the same. I check my ignition periodically after having had one original coil go out and hamper performance. It’s a subtle reduction in power from this fault.

Kappi2907

How do you check the correct workjng?
I Use a ‘induction’ pen to check, very handy but doesn’t provide accurate information.

John McM

i have a vehicle digital multimeter with a RPM input. I just put the induction probe over a lead off each distributor and see if I get a reading.

You could just just take a coil output lead off the distributor and see if there are any changes, but I don’t like disturbing wiring if I can do it another way.

Kappi2907

Ok, that ‘s the method using an induction pen.

Silvertarga

bench testing isnt the best, heat gets to the coils and then its tow truck time