header to head sealant

[Happy Pappy]

Hey All,
I am going to have to use a sealant between the header & my cast IRON HEADS. Is there a preferred silicone or whatever material that really works well for this gasket.
I have used the orange stuff before just not for this application, and the black for oil pan and intake end sealing. Just not sure what works the best for exhaust.
Thanks,
Chris
Should add this is for an AIR Roadster so no sensors.

[manta22]

Red RTV is the highest temperature grade.

[jimmy six]

Yep...... If it's a SBC the multi-layer aluminum ones are the only ones worth a damn on our dirt track car with the long rear crossover headers even supported.
 The only seal on our GMC 12 port nitro engine was the red RTV and 3/8" header flange.