I don't think I'd waste those heads on your current bottom end. I agree that you need a bigger cam. Maybe something in the .480-.500 lift range and 290-300 duration. I'd probably step up to a 750 carb too.pillability said:
horsepower guess
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Driven, thank you. That's pretty much where I was hoping. I have a 2400 stall, (and only 2.56:1 rear right now), and with the 200-4R, I am hoping for mid 20's hwy mpg, but decent overall power. Now to get it wired and plumbed, and driving!
Driven, thank you. That's pretty much where I was hoping. I have a 2400 stall, (and only 2.56:1 rear right now), and with the 200-4R, I am hoping for mid 20's hwy mpg, but decent overall power. Now to get it wired and plumbed, and driving!
Driven, thank you. That's pretty much where I was hoping. I have a 2400 stall, (and only 2.56:1 rear right now), and with the 200-4R, I am hoping for mid 20's hwy mpg, but decent overall power. Now to get it wired and plumbed, and driving!
Sorry all for the duplicate posts....my phone had a mind of its own. When I get on the pc tomorrow, I will clean up the posts.
Sorry all for the duplicate posts....my phone had a mind of its own. When I get on the pc tomorrow, I will clean up the posts.
so you dont think i can hit 300 with those heads? if i can ill stick with that cam the thing is i need some numbers so i can make sure i get the right stall because obviously the bigger problem than that cam is the heads.
I don't think the heads alone will get you to 300hp. They'll probably cost you some torque too. Even though you aren't making big hp numbers now you're making great tq with the combo you have. Right now you have a great engine for a 3 speed and tall gears. Don't think of your engine as a problem that needs to be fixed. There's much more to performance than peak hp numbers. Depending on the gearing etc, a 300hp/400tq can "outrun" a 400hp/300tq. As far as stall speed goes, you're probably safe with an RV type 2200ish convertor.
Another thing to consider is mpg. Typically you can maximize this by cruising where your peak tq is. Yours makes peak tq at 2000rpm. That tells me that you need tall gears to get the best mpg. The 400 in my El Camino still gets 20+ because it's geared to do 70mph at 2200rpm. My peak torque (440) is between 2000-2200rpm.
Another thing to consider is mpg. Typically you can maximize this by cruising where your peak tq is. Yours makes peak tq at 2000rpm. That tells me that you need tall gears to get the best mpg. The 400 in my El Camino still gets 20+ because it's geared to do 70mph at 2200rpm. My peak torque (440) is between 2000-2200rpm.
DRIVEN said:
He's correct Horsepower sells but Torque wins races. Torque is what gets you off the line. Horsepower really doesn't come in to effect till 5,252 RPM.
John Lingenfelter often used to say "Build for torque and the horsepower just takes care of itself".
If you compare Chevelles to GTOs in the 60's you'll see that the Chevelles frequently had lower (3.73-4.11) gears. They needed them because Chevy engines are more peaky and usually make higher hp numbers. The Pontiacs are famous for making torque so 3.55s can be considered a deep performance gear in a GTO. In '66 a 396 and a 389 ran very similar quarter mile times. They just went about it differently.
If you compare Chevelles to GTOs in the 60's you'll see that the Chevelles frequently had lower (3.73-4.11) gears. They needed them because Chevy engines are more peaky and usually make higher hp numbers. The Pontiacs are famous for making torque so 3.55s can be considered a deep performance gear in a GTO. In '66 a 396 and a 389 ran very similar quarter mile times. They just went about it differently.
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