Vortecs can't rev?
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Vortecs can't rev?
No matter what head you choose, on which American V8, at some point you will find more cam adds no HP while still hurting the lower RPM.
That's way past the point at which you should have stopped adding more cam, unless you're running a 6000-stall torque converter.
You want the highest average power through the RPM range you actually use. If you're running a T56 or T5 and shifting at 6000, then you also hafta care what your engine gives at 4000 RPM, for racing. For daily, you gotta care what it makes down around 2500 because a 3000-stall sucks in commuting.
So, giving up 15 ft-lbs at 2500 to gain how much at 6000?
Noone can decide that for you, it's personal preference.
What I can tell you is there's no point in camming a Vortec-headed 350 for 6500 RPM. If that's what you want, get better heads.
When you run a couple dozen cans through a Vortec 350, on an engine Dyno, with an 850 on RPM Air Gap and 1.75" long tubes with extensions, you can find the point at which you obviously went too far.
With enough tuning, you can get a 230/236-110 to work in a Vortec-headed 383. 450 at 5600 has been done, I did it when I didn't believe the magazine results. It took hours of tuning, excellent ring seal, valve lapping, and a lot more.
But that's not a build I would ever do again.
If 400 isn't enough, it's time for better heads, or boost, or an LSx, or a big block. Of those options, the truly cheapest option is a pair of Dart 180 heads. AFR works as well but costs more.
That's way past the point at which you should have stopped adding more cam, unless you're running a 6000-stall torque converter.
You want the highest average power through the RPM range you actually use. If you're running a T56 or T5 and shifting at 6000, then you also hafta care what your engine gives at 4000 RPM, for racing. For daily, you gotta care what it makes down around 2500 because a 3000-stall sucks in commuting.
So, giving up 15 ft-lbs at 2500 to gain how much at 6000?
Noone can decide that for you, it's personal preference.
What I can tell you is there's no point in camming a Vortec-headed 350 for 6500 RPM. If that's what you want, get better heads.
When you run a couple dozen cans through a Vortec 350, on an engine Dyno, with an 850 on RPM Air Gap and 1.75" long tubes with extensions, you can find the point at which you obviously went too far.
With enough tuning, you can get a 230/236-110 to work in a Vortec-headed 383. 450 at 5600 has been done, I did it when I didn't believe the magazine results. It took hours of tuning, excellent ring seal, valve lapping, and a lot more.
But that's not a build I would ever do again.
If 400 isn't enough, it's time for better heads, or boost, or an LSx, or a big block. Of those options, the truly cheapest option is a pair of Dart 180 heads. AFR works as well but costs more.
Joined: Jan 2005
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From: Hurst, Texas
Car: 1983 G20 Chevy
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Re: Vortecs can't rev?
No matter what head you choose, on which American V8, at some point you will find more cam adds no HP while still hurting the lower RPM.
That's way past the point at which you should have stopped adding more cam, unless you're running a 6000-stall torque converter.
You want the highest average power through the RPM range you actually use. If you're running a T56 or T5 and shifting at 6000, then you also hafta care what your engine gives at 4000 RPM, for racing. For daily, you gotta care what it makes down around 2500 because a 3000-stall sucks in commuting.
So, giving up 15 ft-lbs at 2500 to gain how much at 6000?
Noone can decide that for you, it's personal preference.
What I can tell you is there's no point in camming a Vortec-headed 350 for 6500 RPM. If that's what you want, get better heads.
When you run a couple dozen cans through a Vortec 350, on an engine Dyno, with an 850 on RPM Air Gap and 1.75" long tubes with extensions, you can find the point at which you obviously went too far.
With enough tuning, you can get a 230/236-110 to work in a Vortec-headed 383. 450 at 5600 has been done, I did it when I didn't believe the magazine results. It took hours of tuning, excellent ring seal, valve lapping, and a lot more.
But that's not a build I would ever do again.
If 400 isn't enough, it's time for better heads, or boost, or an LSx, or a big block. Of those options, the truly cheapest option is a pair of Dart 180 heads. AFR works as well but costs more.
That's way past the point at which you should have stopped adding more cam, unless you're running a 6000-stall torque converter.
You want the highest average power through the RPM range you actually use. If you're running a T56 or T5 and shifting at 6000, then you also hafta care what your engine gives at 4000 RPM, for racing. For daily, you gotta care what it makes down around 2500 because a 3000-stall sucks in commuting.
So, giving up 15 ft-lbs at 2500 to gain how much at 6000?
Noone can decide that for you, it's personal preference.
What I can tell you is there's no point in camming a Vortec-headed 350 for 6500 RPM. If that's what you want, get better heads.
When you run a couple dozen cans through a Vortec 350, on an engine Dyno, with an 850 on RPM Air Gap and 1.75" long tubes with extensions, you can find the point at which you obviously went too far.
With enough tuning, you can get a 230/236-110 to work in a Vortec-headed 383. 450 at 5600 has been done, I did it when I didn't believe the magazine results. It took hours of tuning, excellent ring seal, valve lapping, and a lot more.
But that's not a build I would ever do again.
If 400 isn't enough, it's time for better heads, or boost, or an LSx, or a big block. Of those options, the truly cheapest option is a pair of Dart 180 heads. AFR works as well but costs more.
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