I Have a 1985 AH Civic Runnin 1.5L 12 Valve Motor.. Got the rev tacho, Digital clock , Import taillight RED Middle strip,Sunroof,Grey with colour coded bumpers,5spd.. All Emissions junk removed

Have been Thrashing Around with it for a few years now.. Only mod being a 32/36 webber on it ..Whats a safe rev limit cos iv found i can rev pretty high(7500rpm) but have blown a few Cam belts ,hole in piston , head gaskets,and generally killing it all the time . Thinkin maybe i should stay under 6000rpm.. Iv got a standard carb back on it , but it runs like shit , so goin back to the webber.. but dont wanna kill it again ..Also got some extractors but never got em on ..Thinkin maybe a cheap straight thru and them would help.. Iv got a few parts and a spare car wrecking .
So if i get 1 PQ point i can make a F/S Advert ..Help a Brother Out