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Marco, It would be great to blabber about my engine! The car setup stems from past autocrossing and winding mountain roads that I used to drive, my dream used to be to run the Chimney Rock hillclimb in NC before they cancelled it. I wanted an engine to be as light as possible with a broad torque curve. The max HP number isn't important. When I use a car in an autocross or road coarse, I find that it is a huge advantage to sometimes stay in a gear when you might otherwise shift, a car with better low end torque can be faster than one with a big max HP number. It is hard though to design an engine and force yourself to pick a slightly smaller cam etc.
I bought my block and rotating assembly from Kieth Craft and did everything else myself. I used Dynosim to determine valve timing.
Dynosim shows that it should be 536@6000 HP and 528@4500TQ . but I haven't dynoed it yet. I think it would be much less because I haven't yet had good headers made. Stock headers are limited by narrow bolt pattern, my AFR heads have an extra set of bolt holes further out to allow headers to match the port but I haven't found a supplier yet.
I wanted a durable engine that wasn't going to do stuff like bend pushrods.
The valvetrain is hydraulic roller and was actually somewhat designed around the valve springs. The springs are the new Comp beehive that have lighter pressure but better high speed bounce prevention. The valves and retainers are titanium. The cam is a custom Comp with 240, 244 @ .050. It has the fast acceleration ramps of a roller but gentle enough to be able to use the softer springs. The lifters are stock dogbone types that I modified the hydraulic travel to be much less. The have to be setup with care like a mech. but they don't have all that extra travel to create pumping up and collapsing. here's the engine specs:
Dart Alum block 4.125 bore
Eagle 4340 crank 4. stroke, Eagle H-beam rods.
Custom JE pistons 10.8:1
AFR 205 heads
Comp hyd. roller 240, 244 @.050 (set at 3 deg. retarded)
Victor jr
BG 850 carb.
MSD dist. 32 degrees total (also has 8 deg vacuum advance, 16 deg mech. , I could write a book on why I want it just that way)
MSD 6AL 6600rpm limit
Alum. flywheel with Mcleod street twin clutch, tilton hyd. bearing.
The engine seems to be a pleasant daily driver. It always starts right up, never gets hot and has good road manners. It's a given that any engine like this has power that can overwhelm the car. I measured gas mileage on a road trip and it was 18mpg hwy. It has been a sucsess beyond my expectations and it's almost boring because it just works well, except for headers, there's nothing more for me to do to it!
It would be a pleasure to meet up sometime, your vette sounds like somthing I'd like to hear about as well.
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