*This is from a email* he said the comp test was around 74psi but thats because the streetport n corner seals????????? I only use Mazda 2 piece apex seals. I was in their competition parts program and got good deals on the comp parts. issues were the little rubber plugs in the corner seals- not the apex seals. rubber plugs seal up at low cranking speeds. They also blow out at high rpm and boost. I replaced these corner seals with solid seals that dont seal as tight at low speed. Atkins web site and look up his race corner seals. All this is explained there. The real way to measure compression pressure on a rotary is a special precording unit that Mazda dealers have. wouldnt be suprized that the pressure is higher than what the bouncing gauge has. the gauge for an indication if a apex seal is blown or not- (in reality you can hold your thumb in the hole and tell if a seal is bad. boost rises. This car will spin the rear wheels in a second gear upshift- Compression is not an issue in my opinion- great hot or cold. The seals are about 10mm high and I have never seen much wear- certainly not enough to cause low compression. both cold and hot starts. send another if you want. you have a PC or apple? I can test it again The onlt time when I have any apex seal breakage is when the hose came loose from the boost controller and the boost was unregulated. Too much boost will certainly break any seal. Thats the reason I liked the Mazda seals- if something does go wrong the seals crumble rather then shatter and there are nor little pieces of super hard steel tearing up housings etc, Each seal is about $60 from Mazda so its not too bad to replace a set. I understand if you are gun shy-Dont know if you do you own work or not. I have raced rotaries for many years and probably underestimate a lot of this. Still I dont like to repair motors if not necesary- thats why I spent so much time on the support systems like oil temp, oil pressure, baffling and intake air temp.
Posted on: Mon, 24 Mar 2014 00:42:03 +0000