Well, typically a good strong spring is a good thing for a highly modified motor...BUT you don't want the spring so stiff that it won't flex down...if your spring is too tight it can cuase the apex seal to brake down prematurely and also scratch the housings walls rendering them useless in a rebuild. The apex seals are made of many different types of metal. You can get them in iron, ceramic, carbon fiber, steel, aluminum(i think), and many other combos. I think stock on the 13B was steel...older 12As used cast iron ones...I'm not positive though...when I rebuild mine..I'm probably gonna use 3mm seals so I can run a higher boost w/ the bridgeport and t78 turbine https://www.nopistons.com/forums/pub...IR#>/smile.png

Rotaryman are you going to or are currently running a bridgeport with a turbo. I thought you could only run a turbo with an extend port. I could be wrong tho, id be interested to see if its possible.

I'm not currently running the bridgeport w/ large turbo...its just a future plan. It is possible...I think its Jbridge and peripheal that you cant do...dunno..could be wrong..

It would be interesting to see the outcome of a bridgeport combined witha turbo. I have never seen it done. Have seen lots of turbos with large extend ports. My gut feeling is that it would run particularly well.

I know of a few people with both a bridegeport and large turbo. One car was spinning warmed up slicks! :wow: