FelPro Stopper gaskets
http://www.aftermarketnews.com/Item/...d_sealing.aspx
http://www.corvetteonline.com/featur...-head-gaskets/
Their website seems totally useless.
I know Cosworth have been selling "stopper" gaskets for a while for some imports, and they've been working very well on some big power cars. I assume they too must be Felpro if using this same "Stopper" feature.
There are a few guys with 800+ Subarus using the Cosworth Stopper gaskets in the UK with great results, although with heavier head studs. They work far better than the normal MLS gaskets so far.
Higher rpm's and power will create higher thrust loadings on the bores and more risk of bore flex. It doesnt say it will help the higher rpm's. They basically say it is designed to withstand the harsher environment of modern day powerful engines before a failure may occur..






