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Trevor Triumph
05-11-2003, 08:42 PM
As summer nears and I have time again, my wife's Spitfire is calling... We're rebuilding the 1500 engine and have installed high compression pistons, secured a 4 into 1 header, bought a twin carb manifold and two S.U. carb puzzles. I don't know what is in the car now... actually the cam is in a box on the garage floor... I figure since the engine had the low compression pistons, the single Stromberg carb, and the cast exhaust manifold, the cam is stock as well. Now my questions, do I want to add a hotter cam? Is there a way to determine if the old cam is stock? We don't intend to race the car but we would use the car to travel to Triumphest, Las Cruses NM, and such; in other words hundreds of miles often on the Interstate. Any suggestions? (Our current Spitfire, Trevor, a MkI screams at Interstate speeds and the automatic hill detector works very well: forty-five MPH up the hill into Flagstaff AZ is quite scary.) T.T.

Bob Claffie
05-12-2003, 12:44 AM
Trevor; Based on Spitfire experiences quite some time ago and using fuzzy math, my best guess that your 1500 will be turning around 4500 at 75 mph. It doesn't make any difference which cam you use- speed equals revs. If you have OD that would chop a few hundred revs off my guestimate. (My FP SCCA Spitfire would just about hit 100 at 7200 rpms with a 4.55/1 rear end gear, no OD). Bob

MDCanaday
05-12-2003, 11:42 PM
Trevor, the best thing to do is contact integeral cams they can re-grind your cam to whatever you want.Also have the old lifters re-faced, much cheaper than AM lifters & much superior(many bad AM lifters out there). You might also want to invest in some balancing of the crank& rods, that way at 4500 you and your fillings wont part ways.
MD(mad dog)