The Only 3300 lb. Buick V6 in the 8s using...

[Alky V6]

I don't believe you did.

If you answer yes then it means your heads are not a restriction. If you answer no then it throws out the argument that you can make more power with more stroke. Either answer will go against what your claiming in this thread.

To fill the extra cylinder volume to make more power requires more air in the cylinder. If your head is holding you back as you claim then you can't gain power. Extra stroke can only make more power when it can get the air required to do so.

I did, Dusty. You just aren't paying enough attention. The answer is NO to your specific scenario. Now, go back and answer the two engine comparison questions I put to you. Pay very good attention to how the questions are phrased. It's like an ASE question. You have to pay attention to the details of the question to hope to answer them correctly, AND learn anything from the exercise. It's all in the details. After you answer the questions, I will clue you in to what the true variable is that makes the difference, AND why cubes is king, all things considered.

key phrase; All things considered.

 

[Alky V6]

I actually did a lot of sim work on the very question Dusty put to me. For my own project, and also for someone else on this board. If you go back and pay better attention to what I posted you may just be able to pick out what I learned from the exercise.

key phrase; Pay better attention.



turbo nasty does NOT like this very much.

Sorry 'bout that. Pick up your reading comprehension skills.

 

[Dusty Bradford]

I did, Dusty. You just aren't paying enough attention. The answer is NO to your specific scenario. Now, go back and answer the two engine comparison questions I put to you. Pay very good attention to how the questions are phrased. It's like an ASE question. You have to pay attention to the details of the question to hope to answer them correctly, AND learn anything from the exercise. It's all in the details. After you answer the questions, I will clue you in to what the true variable is that makes the difference, AND why cubes is king, all things considered.

key phrase; All things considered.

That's all I was looking for. You said you could make more power with more stroke and I disagreed. You have to change the heads as well to gain power from stroke change alone. I just don't want you telling these guys they can put a 3.625 stroke on a stock headed engine and gain power. That's the impression you were giving.

On to the other issue with ci. Take the 281ci mod motor example. Just say he shifts at 9200 rpm to maximize the power. He won't gain power by changing the stroke to make it 352ci but he will be able to shift the motor at 8500 for example to get better durability from the combination. It makes the same power, runs the same et, spools the turbos faster and will be a more durable motor. He can do the same with the smaller motor but it has to make more revs during the 1/4 pass to get equal filling of the cylinder.

 

[Alky V6]

That's all I was looking for. You said you could make more power with more stroke and I disagreed. You have to change the heads as well to gain power from stroke change alone. I just don't want you telling these guys they can put a 3.625 stroke on a stock headed engine and gain power. That's the impression you were giving.

On to the other issue with ci. Take the 281ci mod motor example. Just say he shifts at 9200 rpm to maximize the power. He won't gain power by changing the stroke to make it 352ci but he will be able to shift the motor at 8500 for example to get better durability from the combination. It makes the same power, runs the same et, spools the turbos faster and will be a more durable motor. He can do the same with the smaller motor but it has to make more revs during the 1/4 pass to get equal filling of the cylinder.

Very good, Dusty. I like this post. Finally you worded it in a fashion that I can agree with. Again, if you go back and pay very good attention to what I wrote on the subject, I think you will figure out that I was making VE a very important part of the subject of 'cubes is king'. I wanted people to realize that simply adding cubes is not always the answer. Take my project for example.

If you will remember, I stated that I wanted to rev my engine to a higher operating range than what was typical in the Buick community. I just don't consider an engine that redlines at 6500 rpm to be a 'racing engine'. Sorry if that upsets some out there. That's just how I feel.
Knowing the flow capabilities of the heads, I picked a stroke that would get me to, what I considered, a reliable rpm limit for a racing engine. 7800 rpm redline has proved to be a very reliable and durable rpm limit. I made the right choice there. Camshaft and manifolding design was then picked to support the stroke and rpm limit I picked. As you can see from the results, my very first major engine configuration and design project turned out to work out pretty good. I'm very proud of my first effort.

 

[Alky V6]

I need to add that if one chooses a relatively high rpm operating band for their engine, the right components need to be picked to support that effort. I don't want to see 109ers going out and revving their stock crank and rods to 7800 rpm. They're dealing with a time bomb as it is. Don't make it worse.

 

[Street Lethal]

Wow, lot's of haters in this thread lol. I will say that I entered this thread giving an opinion as to why Don achieved his results, but I left learning a great deal from everyone here. In the end, everyone here are enthusiasts, so can't we all just get along... :tongue:

Again, nice work Don!

 

[Dusty Bradford]

Very good, Dusty. I like this post. Finally you worded it in a fashion that I can agree with. Again, if you go back and pay very good attention to what I wrote on the subject, I think you will figure out that I was making VE a very important part of the subject of 'cubes is king'. I wanted people to realize that simply adding cubes is not always the answer. Take my project for example.

If you will remember, I stated that I wanted to rev my engine to a higher operating range than what was typical in the Buick community. I just don't consider an engine that redlines at 6500 rpm to be a 'racing engine'. Sorry if that upsets some out there. That's just how I feel.
Knowing the flow capabilities of the heads, I picked a stroke that would get me to, what I considered, a reliable rpm limit for a racing engine. 7800 rpm redline has proved to be a very reliable and durable rpm limit. I made the right choice there. Camshaft and manifolding design was then picked to support the stroke and rpm limit I picked. As you can see from the results, my very first major engine configuration and design project turned out to work out pretty good. I'm very proud of my first effort.

6000-6500 rpm is typical for the 109 guys. 7500 range is normal for the Stage 2 guys so I call 7500 or so typical for the racing community. I have several customers who spin them over 8000. 9000....yes, some go there as well.

 

[Alky V6]

6000-6500 rpm is typical for the 109 guys. 7500 range is normal for the Stage 2 guys so I call 7500 or so typical for the racing community. I have several customers who spin them over 8000. 9000....yes, some go there as well.

Now that is something that really irks me. A Stage II headed racing engine with a redline of 7500 rpm. What a complete waste. I can understand the turbo spooling point of lowering the rpm limit, but still, what a little nitrous wouldn't do to take care of that and allow one to push those heads to where they really want to live.
If you're going to bother with Stage II heads, make us proud and push those suckers to 9,000!

You guys are SO lucky I didn't start my project out with bitchin Stage II heads.

 

[Alky V6]

With stroke and a given small port or valve, you have 2 choices. Increase stroke and have the port choke earlier in the rpm band, or decrease stroke and have the port choke at a higher rpm. Of course, there are trade offs in both situations. Engines optimized for each stroke scenario, but using the same intake valve and port would end up being very closely matched as far as 1/4 mile performance.

Here you go, Dusty. Here is the answer I made to your question that you and some others chose to ignore way back in this thread. Post 107, page 3. I admit, I kinda snuck it in there to see if anyone was paying attention. None the less, there it is.




turbo nasty really, really, REALLY does NOT like this.

Sorry.

 

[Dusty Bradford]

Now that is something that really irks me. A Stage II headed racing engine with a redline of 7500 rpm. What a complete waste. I can understand the turbo spooling point of lowering the rpm limit, but still, what a little nitrous wouldn't do to take care of that and allow one to push those heads to where they really want to live.
If you're going to bother with Stage II heads, make us proud and push those suckers to 9,000!

You guys are SO lucky I didn't start my project out with bitchin Stage II heads.

It's not a waste. It's simple reasoning. The maint on a 9k rpm motor is alot different than on a 7500rpm motor. Now consider an engine that makes 1600-1700 hp at 7500 rpm compared to one that makes 1800-1900 at 9000rpm. Durability is a big driver in sticking with the lower rpm range.

I can understand the turbo spooling point of lowering the rpm limit, but still, what a little nitrous wouldn't do to take care of that and allow one to push those heads to where they really want to live.

How would lowering the rpm limit help with turbo spooling? In the real world raising the rpm limit helps to spool the turbo. With the extra rpm range you can loosen the converter to help spool and then the rpm brings the efficiency back in line. If a car shifts at 8500 vs 7500 but makes similiar power, I can loosen the converter nearly 1000 rpm.

 

[Alky V6]

It's not a waste. It's simple reasoning. The maint on a 9k rpm motor is alot different than on a 7500rpm motor. Now consider an engine that makes 1600-1700 hp at 7500 rpm compared to one that makes 1800-1900 at 9000rpm. Durability is a big driver in sticking with the lower rpm range.



How would lowering the rpm limit help with turbo spooling? In the real world raising the rpm limit helps to spool the turbo. With the extra rpm range you can loosen the converter to help spool and then the rpm brings the efficiency back in line. If a car shifts at 8500 vs 7500 but makes similiar power, I can loosen the converter nearly 1000 rpm.

I'm just saying, durability would have to take a back seat if I had the chance to build an engine with heads that rocked the world. I would make the heads the limiting factor, much the same approach I had with this present engine.
There is nothing that I've learned from this build that I would hesitate to apply to a set of Stage II heads.

Dusty, you need to learn how to not contradict yourself. Read your post #303, second paragraph.

 

[Dusty Bradford]

I'm just saying, durability would have to take a back seat if I had the chance to build an engine with heads that rocked the world. I would make the heads the limiting factor, much the same approach I had with this present engine.
There is nothing that I've learned from this build that I would hesitate to apply to a set of Stage II heads.

Dusty, you need to learn how to not contradict yourself. Read your post #303, second paragraph.

He won't gain power by changing the stroke to make it 352ci but he will be able to shift the motor at 8500 for example to get better durability from the combination. It makes the same power, runs the same et, spools the turbos faster and will be a more durable motor.

LOL. I assume your talking about the part in bold??

Nothing contradictory, just your lack of understanding. A longer stroke crank spools a turbo easier. That's something you don't learn from sims.

I'm sure your just trolling for input from the Stage 2 guys with your comment about the heads. Truth is there's nothing that rocks the world about a Stage 2 head. It's just a large sloppy hole that flows a respectable amount of air. It's being proven that a raised runner conventional style GN1 will make similar power. And the GN1 will boost low end torque over that large sloppy port of the S2.

 

[Alky V6]

LOL. I assume your talking about the part in bold??

Nothing contradictory, just your lack of understanding. A longer stroke crank spools a turbo easier. That's something you don't learn from sims.

I'm sure your just trolling for input from the Stage 2 guys with your comment about the heads. Truth is there's nothing that rocks the world about a Stage 2 head. It's just a large sloppy hole that flows a respectable amount of air. It's being proven that a raised runner conventional style GN1 will make similar power. And the GN1 will boost low end torque over that large sloppy port of the S2.

I see. Thanks for clarifying.
I was looking at it from the point of view that if someone was shooting for a lower rpm band to operate at, the different cam specs would allow for more cylinder pressures at lower rpms, following the argument that less duration cams will spool a turbo quicker.

No trolling. Actually, I worked out a Stage II configuration years ago. I'd have to take a good hard look at the current heads available myself before I passed on using a Stage II head, if the target was an ultimate Buick V6 build. Low end torque would really be of little concern to me. I happen to have a way around that problem.

That being said, I do have a lot of investment in manifolding, so the most inexpensive way for me to upgrade performance would be to stick with a Stage I style head. A raised intake port would be part of the plan. Mike's heads have plenty of meat to take the port up a good amount. Don't know how high anyone has taken a Stage I intake port actually. I wouldn't be constrained by intake manifold design, so I'd shoot for as high as possible to get the best numbers, then just redesign my present intake to match.

 

[bison]

A Stage II headed racing engine with a redline of 7500 rpm. What a complete waste.
If you're going to bother with Stage II heads, make us proud and push those suckers to 9,000!

You guys are SO lucky I didn't start my project out with bitchin Stage II heads.

Apparently you dont see the valvetrain limitations of this engine. 9000 rpm. Yeah right. Why dont you go and pick up a set of stage 2 heads and humor us? Why dont you nail down your suspension issue(s) and turn the boost up to the 45-50psi it needs to really crank it out. You would be just about right there with those bad ass stage 2 (and TA) head guys and still have the small valves.

 

[Alky V6]

Apparently you dont see the valvetrain limitations of this engine. 9000 rpm. Yeah right. Why dont you go and pick up a set of stage 2 heads and humor us? Why dont you nail down your suspension issue(s) and turn the boost up to the 45-50psi it needs to really crank it out. You would be just about right there with those bad ass stage 2 (and TA) head guys and still have the small valves.

You really think it has it to do that?

 

[bison]

You really think it has it to do that?

I see about another half second there. The fact that you have that wide power spread up top says enough about the airflow through the engine. If those valves were hurting it that much it would drop power. If you increase the boost you aren't increasing the flow through the engine. Maybe only to a small extent because of the intake to ex pressure you have currently. The piston will be enough to clean out the cylinder with the low backpressure. The low backpressure is effectively increasing the intake duration for you which is exactly what you need with those heads. Quit posting and simming and go make some suspension changes and throw power at it.

 

[KL Mallender]

For consideration: 3150 lb vehicle trapping 158 mph looks to need right close to 950 hp to accomplish it, perfected ET would be 8.60 for that mph.

So, that would work out to 4.24 hp per cubic inch on Donnie's 'lil screamer. and only being off by 0.17 in ET say's he's making damm fine use of that hp.

Power number per cube should put most 276 cubers at 1170 to be comparative.
That power should put the same weight vehicle(3150) down the track at 8.10 @ 168 mph, that's what I come up with comparing apples to apples.

Kevin.

 

[bison]

Haterade just sent me a pm and said you don't have the balls to turn it up

 

[Alky V6]

Apparently you dont see the valvetrain limitations of this engine. 9000 rpm. Yeah right. Why dont you go and pick up a set of stage 2 heads and humor us? Why dont you nail down your suspension issue(s) and turn the boost up to the 45-50psi it needs to really crank it out. You would be just about right there with those bad ass stage 2 (and TA) head guys and still have the small valves.

Yes, 9000 rpm. I'm not going to argue with anyone about my Stage II setup. That configuration is not up for discussion.

 

[Alky V6]

Haterade just sent me a pm and said you don't have the balls to turn it up

Hah! You both would have lost that bet. I already have. Guess what happened. Man, some of you guys just don't pay attention.
Still ignoring track conditions, I see.