[pastry_chef]

To add to my above information.
Increased rocker ratio to 1.8
.400 lobe HYD ROLLER.
Asked for best power from 4500 to 6500 RPM.

Ended up adding about 14 HP to the averages.


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[slowbird]

Pastry Chef how accurate is that simulator?

[pastry_chef]

Originally Posted by slowbird

Pastry Chef how accurate is that simulator?

It is excellent to compare trends, used by many pros.
I don't rely on any one tool I have, it is just one more.

[slowbird]

Originally Posted by pastry_chef

It is excellent to compare trends, used by many pros.
I don't rely on any one tool I have, it is just one more.

Im just curious why it added 5-9 more degrees just because you added 1.8 rockers

[pastry_chef]

Originally Posted by slowbird

Im just curious why it added 5-9 more degrees just because you added 1.8 rockers

The simple answer is insufficient valve lift is a top end bottleneck. So the bias leans towards improving lower range power to get the best average it can.

[slowbird]

Originally Posted by pastry_chef

The simple answer is insufficient valve lift is a top end bottleneck. So the bias leans towards improving lower range power to get the best average it can.

Interesting, with a high valve to bore ratio i wouldn't think it would be that lift sensitive

[pastry_chef]

I can say increasing port velocity can reduce the net valve lift required.

[Formulajones]

Originally Posted by Dragncar

Nice post, you get it. The LS is a fantastic engine with some similarities to our Pontiacs. We need to learn from them and use it where we can in our old engines.
Your BBC makes great power for a 242/ 248 cam. I do not know of any Pontiacs getting that (600-600) done with such small a cam.
Cam-ing a engine is about keeping the air accelerating so you can accelerate the car. And that does not mean max lift-max cfm.

Thanks, I agree it's a pretty small cam. AFR makes an exceptional head, helps this engine make the power it does, even though the head is on the large side for the engine.

[Formulajones]

Originally Posted by pastry_chef

Don't look at CC volume, BBC have longer ports.

The AFR 305 has a small throat, a min CSA of 2.993 sq. in. The mean CSA is just a bit larger, close to 3.
This said, For a 461 engine the AFR 265 will kill an AFR 305 on the dyno up to 5000 RPM. All things the same. Peak power not much different if correctly cam'd.
The AFR 290 is the beast I'd want to make BBC power up to 7000 RPM. minCSA 2.895 sq. in. An explosive head.

Only some of them. They aren't all the same length on a BBC, unlike a Pontiac. Regardless, the port is still fist size and according to most here, should be horrible at making low speed power. But that hasn't been the case That's why I used the example as it directly related to the OP's original question.

The AFR 265's and 290's weren't even around back when I bought my 305's. And while I don't doubt the 265's may be a great head, as I've never seen a junk AFR anything, I'd sure like to see them on the dyno compared to a 305 before I made any claim that they "kill". Coming from a lot of years using the 305's myself they do a pretty damn good job on a little engine. It's for these reasons a wide port that is said to be about 275cc wouldn't scare me in the least on a 461 Pontiac, especially with a 4.210 crank.

[slowbird]

Originally Posted by Formulajones

Only some of them. They aren't all the same length on a BBC, unlike a Pontiac. Regardless, the port is still fist size and according to most here, should be horrible at making low speed power. But that hasn't been the case That's why I used the example as it directly related to the OP's original question.

The AFR 265's and 290's weren't even around back when I bought my 305's. And while I don't doubt the 265's may be a great head, as I've never seen a junk AFR anything, I'd sure like to see them on the dyno compared to a 305 before I made any claim that they "kill". Coming from a lot of years using the 305's myself they do a pretty damn good job on a little engine. It's for these reasons a wide port that is said to be about 275cc wouldn't scare me in the least on a 461 Pontiac, especially with a 4.210 crank.

Just to compare apples to apples a 305cc bbc head has a rough average cross sectional area of 3.10, while a Butler wide port is 3.25. A bbc with that average would almost be 325cc.

[Formulajones]

Not enough to sway me in a decision either way. I've never been of the opinion heads in this range are too large for a 450-470 ci engine based off what I've done with them in a street car.

Just an FYI, the 305's turn into 315's with the CNC port option. So your nearly into your port dimension comparison with very little CC gain.

[slowbird]

Pasty Chef can you run a cam similar to what Stan should from 4500 to 6500 like the others. Just wondering how it stacks ups

[Dragncar]

Originally Posted by slowbird

I never ran ti valves! Your so full of misinformation and fake news its just stupid now.
Please show me a 496-505 that has made 850+hp with wilcox heads and backed it up with track results. And DON'T say Gach!!
I have saw a text from wilcox where he says he had bench issues and never had a 400cfm port his bench was wrong.
Not even sure why you're posting in this thread, you have offered now useful info.

No Ti valves on your High Ports ? You mean the ones you had in the For Sale section ? The Barton High Ports with both Ti valves for 6000$ . The add is still there ?

[steve25]

Going back to the op's first post/ question, it's not a matter so much of the Cam specs to run,but gearing!

Even with Enough effective Caming to make good use of those heads to the tune of 70% of what they can do, your taking about a torque band even with 461 cubes under the heads that does not really shine until 4000 rpm

On the street you want a minimum of a 5 speed manual trans and 4.11 gears assuming a 28 to 29" tall tire.

[slowbird]

Originally Posted by Dragncar

No Ti valves on your High Ports ? You mean the ones you had in the For Sale section ? The Barton High Ports with both Ti valves for 6000$ . The add is still there ?

Umm those were for racing and saw 9000rpm. The pump gas 496 had stainless and ran fine to 8200rpm. You really need to get your facts straight.
Or are you saying people should turn there e-heads 9000rpm with stainless valves?

[slowbird]

Originally Posted by steve25

Going back to the op's first post/ question, it's not a matter so much of the Cam specs to run,but gearing!

Even with Enough effective Caming to make good use of those heads to the tune of 70% of what they can do, your taking about a torque band even with 461 cubes under the heads that does not really shine until 4000 rpm

On the street you want a minimum of a 5 speed manual trans and 4.11 gears assuming a 28 to 29" tall tire.

Why a manual? An auto with a 4000-4500 stall and 3.73 should be just fine imo.

[Formulajones]

You don't even need that much.

I run a very snug driving Continental in mine that flashes around 3400. Remember this is a street car in the street section, with a small camshaft. There is no need to run a 4500 stall. With the big heads and little cam mine makes peak torque at 3900 and is extremely flat from there and makes peak power at only 6300 rpm. It's a very broad and flat curve with a nice spread between the peaks, despite what some say it should be with large heads. Even with the tight stall it still pulls the wheels and runs 1.5 short times in a 4100 lbs. car. It's still a docile street car. Actually the snug stall works to my benefit, flashing just below peak torque, even though it's still in the 500's at that point, makes it a bit easier to launch and manage the heavy car on the small 275 radial tire I run.

In a Pontiac with a much longer crank for the cube size, a snug stall like this should be even less of an issue. Everyone talks about how much torque their Pontiacs make, it shouldn't have a problem carrying it.

[pastry_chef]

Originally Posted by slowbird

Pasty Chef can you run a cam similar to what Stan should from 4500 to 6500 like the others. Just wondering how it stacks ups

Sure, I can post results tonight.

For best accuracy if you can provide the port minimum CSA and CSA at port entry.

[slowbird]

Originally Posted by pastry_chef

Sure, I can post results tonight.

For best accuracy if you can provide the port minimum CSA and CSA at port entry.

Butler wide ports are roughly 3.35 from entry to pushrod

[Bill Eveland]

What was the projected average hp for this group of cams?

Originally Posted by pastry_chef

To add to my above information.
Increased rocker ratio to 1.8
.400 lobe HYD ROLLER.
Asked for best power from 4500 to 6500 RPM.

Ended up adding about 14 HP to the averages.


268 / 268 @ .050
109 LSA - 107 IC
----------------------------------------------------------
264 / 276 @ .050
106 LSA - 105 IC
----------------------------------------------------------
264 / 268 @ .050
107 LSA - 105 IC
----------------------------------------------------------
268 / 272 @ .050
107 LSA - 106 IC
----------------------------------------------------------
264 / 272 @ .050
107 LSA - 105 IC
----------------------------------------------------------
268 / 272 @ .050
108 LSA - 107 IC