|Dave Dodge - DRP Rebuilds and Racing Engines
Tue Jul 31 11:12:29 2001
To clarify the engine rebuild and building process. A Stage 1 engine blueprint/rebuild freshens the engine to better than new performance levels and condition. Most engines I receive for rebuilding barely make 90 HP at the rear wheel. A V65 Magna in good condition prior to a rebuild consistently makes 96 HP at the rear wheel. After the rebuild and blueprint with stock cams these engines make 98 to 100 RWHP. In other words you should not expect a huge HP increase when using stock parts, but it is better than when you bought it.
Stage 1 cams are used by me as a replacement to stock cams when needed. These cams are close to a stock Sabre grind, but have .010" more lift and 2° more duration. These specs make for a better lobe shape that contacts the rocker arm better. It's an upgrade for when cams are needed.
Stage 2 cams are the biggest you can use with stock pistons and valve springs, but they do need to be degreed-in for best performance and clearances. Installing these cams in a freshly rebuilt engine is good for 8 more horsepower.
Stage 2 engines is when we start adding components to make more power. Typically a Stage 2 engine gets Stage 2 cams and porting. For porting to work at its best you must also address carb jetting and exhaust flow. Keep in mind that increasing head flow does little if it can't get through the engine. Typically a Stage 2 engine makes 110 to 113 RWHP with a header and dyno-tuned jetting.
Stage 3 is the stage when higher compression pistons are used. Stage 4 is the badest engine you can run on pump gas.
Stage 3 and larger (up to 5) cost in excess of $4000.00, so unless you want to spend that kind of money you are limiting your total capability.
The Stage 4 engine for one of the listmembers is being built for street and strip use and will be run on pump gas.
Stage 3 porting and cams, bronze guides, valve springs, titanium retainers, 12:1 compression forged pistons (1134cc), cyro treated crank/rods, racecut trans, and the main part that makes it all work is the 37mm Keihin FCR flat-slide carb set. The carbs alone are $1500.00 and custom built by DRP. The power range on this package will be 125 to 130 RWHP. I will have dyno sheets once complete and the tuning finished.
I hope this explains a little more. BTW, the V65 Sabre typically makes 2-3 more HP than a Magna stock.