Posted: Mon Apr 20, 2009 4:45 pmI've decided to try get some more midrange from my 1949 Power Wagon truck. It's equipped with a 230 cu in flathead that was rated for 95 hp at 3200 rpm- this in a 6800 lb vehicle with a 5.83 rear end. Presently, 45 mph is achievable with the accelerator flat on the floor. The 230 underwent several upgrades over its use in Dodge vehicles that eventually resulted in 120 hp at 3600 rpm by 1960. I want to get more torque in the 25-2700 rpm region, so I'm going to be looking at increasing intake/exhaust flow via indvidual carburetion with 38 MM Mikuni motorcycle carbs, a split exhaust manifold, and valve & valve seat work. The engine has siamese intake ports, so intake tuning is limited to restriction reduction.
I have to flow both the block and the head, and that combo probably weighs in at 200 lbs- a fully equipped 230 is about 600 lbs- it's tractor motor heavy. I'm thinking about bolting the block/head assy to an engine stand, with a cam in the engine. The sparkplug hole is located over the intake valve, so I can get intake valve opening measurements from that hole. Don't want to bore any holes for the exhaust side in my heads, so I'll have to dream up another way for exhaust lift numbers.The flow setup I had in mind closely resembles the David Vizard's original flow bench as pictured in the GFN "floating depression" discussion. I'm quite interested in SEEING what the flow is actually doing, especially at depressions similar to those encountered in a running engine, so I"ll probably try to make a transparent head casting for one cylinder. Valves and valve seat shape is about #1 on the list to investigate. From what I've heard, the engine responds well to induction improvements and supercharging (Don't see myself going there), so with more HP in the midrange I may be able to see 55 with 4.89 diff gears or an overdrive tranny. Anybody "Been there, Done that-Got the T-shirt And the Hat"?
I have to flow both the block and the head, and that combo probably weighs in at 200 lbs- a fully equipped 230 is about 600 lbs- it's tractor motor heavy. I'm thinking about bolting the block/head assy to an engine stand, with a cam in the engine. The sparkplug hole is located over the intake valve, so I can get intake valve opening measurements from that hole. Don't want to bore any holes for the exhaust side in my heads, so I'll have to dream up another way for exhaust lift numbers.The flow setup I had in mind closely resembles the David Vizard's original flow bench as pictured in the GFN "floating depression" discussion. I'm quite interested in SEEING what the flow is actually doing, especially at depressions similar to those encountered in a running engine, so I"ll probably try to make a transparent head casting for one cylinder. Valves and valve seat shape is about #1 on the list to investigate. From what I've heard, the engine responds well to induction improvements and supercharging (Don't see myself going there), so with more HP in the midrange I may be able to see 55 with 4.89 diff gears or an overdrive tranny. Anybody "Been there, Done that-Got the T-shirt And the Hat"?