Thread: encourage bbc 509ci

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Alex, you have made the same mistakes that tens of thousands of other fellows have made when it comes to increasing the performance of their vehicles. You have failed to view your car as a system. You cannot change the camshaft in a motor without changing the torque converter and rear gears to compliment the cam's characteristics. Matter of fact, most fellows would do well to leave the motor alone and change the torque converter and rear gears. I have always championed doing that first and leaving the motor stock until you see if a converter and gears will give a fellow the performance they are looking for.

Originally Posted by Alex-grand

Hello guys
i build big block 509ci, 10.3 compress,
rear gear(stock impala67) - 2.73

Wrong gears. Needs 3.42:1 / 3.55:1 with limited slip.

[QUOTE=Alex-grand;573239] th400 with stock converter(stock stall speed) engine idle^550-650rpm [QUOTE]

Wrong torque converter. Needs 10" diameter, 2000 / 2500 stall unit. Purchase a true 10" converter, not a 12" unit with the fins bent over. Here is an example of what I would use.....10" that stalls about 1,000 rpm's over stock, with anti-ballooning plate and furnace brazed fins. I'm not saying to use this exact converter, just showing you the type of converter that I might use if I wanted a little more power for street driving. Assuming the stock converter stalls at somewhere around 1200 to 1400, then this unit would stall at around 2200 to 2400, which should work well on the street.
https://www.summitracing.com/parts/tci-240901/overview/

Originally Posted by Alex-grand

I have a manifold Edelbrock 7161 range 1500-6000rpm, oval port, Dual plane.

This is the correct intake manifold for a performance street machine.

Originally Posted by Alex-grand

Edelbrock Performer RPM Cylinder Heads 604519
carb: edelbrock 750cfm

750 CFM will not make maximum power with a 509 cubic inch motor, but should provide enough volume to make good power on the street.

[QUOTE=Alex-grand;573239] today I have a camchaft COMP Cams 11-407-8(range idle-4600rpm, lsa110, Dur050 Lift: 200/206, 0.510 int./0.510 exh. [QUOTE]
This is a great street cam for a motor with about 9.0:1 static compression ratio. You are using it with a static compression ratio that is far too high and I would suspect that your cylinder pressure is through the roof. If not operated on very high octane fuel, I would think that you would be detonating the motor.

Originally Posted by Alex-grand

i whant buy new camshaft: edelbrock 2263 . Range: 1,500-6,500, Dur050 Lift: 248 int./256 exh, LSA112, 0.629 int./0.643 exh.

If you think the car is a pooch now, just go ahead and install more cam with the stock gears and converter. You won't even want to drive it any more. The camshaft is not a stand-alone part in the motor. It requires all the other parts and systems in the motor and on the car to be coordinated to work with a certain cam timing. For all you other fellows who are reading this thread, start at the back of your vehicle, with gears, then converter, before you ever change one part in or on the motor.

Originally Posted by Alex-grand

Maybe this Cam aggressive ?

You don't need that much more cam, you need more gear and more converter. With more gear and more converter, the motor could use more cam, but not as much as 248/256, more like 220 or 225 to match up with the static compression ratio a little better.
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