[KSZR]

Originally Posted by SD455DJ

Thanks W.S.GTO! If we built the 400 to the max the pure stock rules allow, I could run as much as 11.5 to 1 compression (1.5 over advertised 10.0), and any hft cam (actually have a 2801 in it now) that maintains 16 in. vacuum at 1200 rpm (changing to 18 in. this year). Higher compression would allow a bigger cam to maintain 18 in. vacuum, so possibly the 2802 could work, but I think the small valves and log manifolds would be corks (with the 2802 cam) above 4000 rpm and counter productive...not to mention the tradeoff of less torque for higher horsepower wouldn't allow better et's in this particular engine (would work well in a RAIII with bigger valves and RA exh. manifolds!). A 3.73 or 3.90 gear would be more ideal too. With some front suspension work along with all the above, it could run 12.70's at 108 mph. If it weighed closer to 3650 lbs, there's a another .15 seconds lower et!

Dennis

Dennis,

My 72 Lemans with 400 .030 over, 068 cam, cast iron intake, log manifolds, HO racing carb and distributor kits, dual snorkel, crush bent quiet exhaust, 3.55 12 bolt, 200 4R does a best 1/4 mile on my dragy of 14.59 at 95.

Going to upgrade to a 2.5" Pypes mandrel system, which sounds like a huge improvement.

What would I gain by going to ram air manifolds over logs? Wondering if its worth it.

Kent