Max N/A power from Gen 3

[rottenronnie]

Someone check my bench-racer math: A port that flows 285cfm at 28", on a 505cid V10, should be good for 670+hp. Subtract 30hp for accessories (I made that number up, so any read data is welcome) and an additional 13% for RC SRT10-like drivetrain losses, and a stock Gen III head should support around 550rwhp, correct? Based on that, a fully ported Gen III head (330cfm @ 28") should be good for right around an additional 93rwhp.

Man, I've seen those tables and, well I guess they could/should work. Do they?
I don't think so, not in the real world.

High cylinder head flow, sells heads when you are in the market for them. Remember the Viper engine already HAS a performance head and Mopar spent a TON of money on development because POWER sells performance vehicles. Can you make improvements in flow and power on a stock head? ABSOLUTELY but only up to a point.

Pro Stock used to "race" flow benches until they found an increase in c.f.m. was producing LESS power than the previous version of the ported head they tried, that actually flowed less.

There is quality of flow.
There is quantity of flow.

And then there is what the engine wants/needs which is a head that produces MAXIMUM power and NOT the maximum possible c.f.m. numbers.

 

[caveman]

Man, I've seen those tables and, well I guess they could/should work. Do they?
I don't think so, not in the real world.

High cylinder head flow, sells heads when you are in the market for them. Remember the Viper engine already HAS a performance head and Mopar spent a TON of money on development because POWER sells performance vehicles. Can you make improvements in flow and power on a stock head? ABSOLUTELY but only up to a point.

Pro Stock used to "race" flow benches until they found an increase in c.f.m. was producing LESS power than the previous version of the ported head they tried, that actually flowed less.

There is quality of flow.
There is quantity of flow.

And then there is what the engine wants/needs which is a head that produces MAXIMUM power and NOT the maximum possible c.f.m. numbers.

I agree with you regarding quantity of flow vs quality of flow. This is where the term "power under the curve" comes from, IMO. That's why I used a stock head (285cfm) for my baseline. Interesting to compare that to a 906/452 RB casting (220cfm)!

 

[rottenronnie]

I agree with you regarding quantity of flow vs quality of flow. This is where the term "power under the curve" comes from, IMO. That's why I used a stock head (285cfm) for my baseline. Interesting to compare that to a 906/452 RB casting (220cfm)!

Yeah the 440 head (stock trim) didn't have much going for it, back in the day.
I saw some radically ported 906s that had a piston burn pattern about 2" across, the rest of the piston top had no indication of combustion, only fuel wash in the form of a shiny aluminum surface.
Big c.f.m. numbers though but no 1/4 mile m.p.h. numbers on the top end (the engines failed to produce good power).

 

[caveman]

Yeah the 440 head (stock trim) didn't have much going for it, back in the day.
I saw some radically ported 906s that had a piston burn pattern about 2" across, the rest of the piston top had no indication of combustion, only fuel wash in the form of a shiny aluminum surface.
Big c.f.m. numbers though but no 1/4 mile m.p.h. numbers on the top end (the engines failed to produce good power).

Is it fair to say that quantity makes WOT peak horsepower (and thereof MPH) while quality of flow produces torque, drivability, responsiveness, etc (E/T)?

 

[rottenronnie]

Higher c.f.m. than what the engine wants will produce LESS power.


Liquid fuel DOESN"T burn so if the A/F mix is upset by a shearing effect (in the case of a poor port design or excessively ported cylinder head) where fuel and air separate, a portion of that A/F mix won't burn.
That will drop power. Burn as much of the A/F inside the cylinder and you will have maximum efficiency.

Quality flow produces power.

 

[Wastelands Warrior]

Thank you for the informative posts, gentlemen.

 

[Greg Good]

Needless to say, Trainman has set the bar for n/a power, but I was wondering what kind of numbers could be had with a more conventional n/a build, as in utilizing the Gen 3 heads and intake.

A decent Viper with a smallish' 232 @.050" cam will routinely make 625-645 without cats.


I think JTS has about the best power I've heard of on a truck with 600'ish.

 

[Greg Good]

A Striker headed Gen 3 could match Jerry's max power levels. Keep in mind that Jerry's build isn't a "max effort" build. All people involved have worked to make sure it's a street able combo that will work well in Jerry's 4400 pound truck.

No. A Striker head will never get a sniff at Jerry's Gen 4 heads.

 

[rottenronnie]

No. A Striker head will never get a sniff at Jerry's Gen 4 heads.

The (unported, in this case) Striker-Rs (Dom's) have no rivals.

 

[Greg Good]

The (unported, in this case) Striker-Rs (Dom's) have no rivals.

Sorry to disagree with you.

 

[caveman]

No. A Striker head will never get a sniff at Jerry's Gen 4 heads.

I was under the impression that Jerry's engine was a street engine, designed with maximum mid range torque, not with maximum horsepower in mind? If that's the case, I would assume that a ported striker R, in a full race application, would build more peak power then Jerry's Gen 4 street heads? I apologize in advance for any strange spelling or punctuation. I'm driving down the road and voice texting because this conversation is just too interesting to leave alone.

 

[rottenronnie]

Sorry to disagree with you.

No problem.

 

[Greg Good]

I was under the impression that Jerry's engine was a street engine, designed with maximum mid range torque, not with maximum horsepower in mind? If that's the case, I would assume that a ported striker R, in a full race application, would build more peak power then Jerry's Gen 4 street heads? I apologize in advance for any strange spelling or punctuation. I'm driving down the road and voice texting because this conversation is just too interesting to leave alone.

Jerry's engine is a racing engine with lowered compression for pump gas and a small cam for street manners.

Put 13.5:1 in it, race gas, and 10 degrees more cam and it would probably make 1000 flywheel.

Non of the Striker heads I have wet flowed did well. They have what I call an "internet port" that is crafted to sell heads to novices who shop for the most cfm per cc of runner volume.

 

[caveman]

Jerry's engine is a racing engine with lowered compression for pump gas and a small cam for street manners.

Put 13.5:1 in it, race gas, and 10 degrees more cam and it would probably make 1000 flywheel.

Non of the Striker heads I have wet flowed did well. They have what I call an "internet port" that is crafted to sell heads to novices who shop for the most cfm per cc of runner volume.

Noted, thanks. Slightly off-topic, but how do the GEN four heads compared to an LS seven GM head?

 

[Greg Good]

They're nearly the same. Except the exhaust port on the Gen 4 head is much better. Mike Chapman of Chapman Racing heads designed the intake ports and chambers on both.

 

[caveman]

Non of the Striker heads I have wet flowed did well. They have what I call an "internet port" that is crafted to sell heads to novices who shop for the most cfm per cc of runner volume.

I have actually heard this before. Do you have any data that you can share with us from the strikers that youve flowed?

 

[rottenronnie]

Non of the Striker heads I have wet flowed did well. They have what I call an "internet port" that is crafted to sell heads to novices who shop for the most cfm per cc of runner volume.

Wow, that is the polar-opposite of what Jeff Morys stated about flowing the high c.f.m. heads you were producing when he checked them on Chrysler's flow benches.

And the ports stalled (which would abruptly limit power).

Also, the c.f.m. numbers were considerably lower than claimed.

Somebody must be wrong here.

Regards.

 

[caveman]

Wow, that is the polar-opposite of what Jeff Morys stated about flowing the high c.f.m. heads you were producing when he checked them on Chrysler's flow benches.

And the ports stalled (which would abruptly limit power).

Also, the c.f.m. numbers were considerably lower than claimed.

Somebody must be wrong here.

Regards.

I don't think anyone is wrong. It's merely a case of different people interpreting the same data differently.

Ironically, I'm about 12 hours from home on my way to look at a striker headed SRT10.

 

[Greg Good]

I have actually heard this before. Do you have any data that you can share with us from the strikers that youve flowed?

The Street Strikers usually flowed about 335. some of the race versions went 355, some more. It seemed like there were two different ports on them. Some of the Race heads had the street ports, just with a bigger valve.

Ported without welding I can get 390 cfm out of a Striker head and make it wet flow good.

 

[Greg Good]

Wow, that is the polar-opposite of what Jeff Morys stated about flowing the high c.f.m. heads you were producing when he checked them on Chrysler's flow benches.

And the ports stalled (which would abruptly limit power).

Also, the c.f.m. numbers were considerably lower than claimed.

Somebody must be wrong here.

Regards.

You're the master of second hand information. That's one reason why you've been on my ignore list for several years. You don't like me. I get it. I don't care much for you either.

Please don't try to pit Jeff and I against one another. The last time he and I spoke was about a set of Gen 4 heads I did for a customer in Ohio. Car had 3.73 gears and made 623 with heads, headers, and a Mopar Controller. Not all that bad. It ran 10.50's at 135 and change in the 1/4. Guy was very happy. He hurt the shortblock and sent it to a shop to have it rebuilt. The shop sent the heads to Dodge to have looked at, and supposedly the report was that they were "Junk". The shop refused to put them back on and made the guy buy a set of their CNCD heads. 20,000 dollars later the car lot 4 tenths and slowed to 10.90's. You be the judge. I say it was politics.

I'm posting from a position of a modest amount of experience. What about you? Talk is cheap...what have YOU done?

I know a little bit about Viper engines. I can make a set outrun a 2000 hp TT Lambo.