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Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 12:28 pm
by Carnut1
randy331 wrote:I meant header pipe size, Do you think a bigger pipe showing more cfm on the bench is going to show up as power on the engine ?

Do you think there's a connection there ?

Randy
Sorry Randy, Even running 8000 rpm I would run the 1 5/8" tube for road race and for drag depending on combo I would still run 1 5/8' tube header.
Do I think there is a connection? I test each exhaust port the same way, all lifts without pipe, ft/sec center of flange @ .7" lift, flow with 1 5/8" pipe @ .7" lift and 1 7/8" pipe @ .7" lift. Why? I think it gives me a good Idea of what the exhaust port will do in application. Some pickup more with the big pipe than others. I think in reality the bigger pipe will show a few extra ponies but at a large loss of torque throughout the usable rpm range. I will take the usable torque please!

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 12:30 pm
by Carnut1
RevTheory wrote:Don't take the bait. You know where this is headed and why.
I know, no matter what I write I will be wrong!

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 12:45 pm
by randy331
Carnut1 wrote:
randy331 wrote:I meant header pipe size, Do you think a bigger pipe showing more cfm on the bench is going to show up as power on the engine ?

Do you think there's a connection there ?

Randy
Sorry Randy, Even running 8000 rpm I would run the 1 5/8" tube for road race and for drag depending on combo I would still run 1 5/8' tube header.
Do I think there is a connection? I test each exhaust port the same way, all lifts without pipe, ft/sec center of flange @ .7" lift, flow with 1 5/8" pipe @ .7" lift and 1 7/8" pipe @ .7" lift. Why? I think it gives me a good Idea of what the exhaust port will do in application. Some pickup more with the big pipe than others. I think in reality the bigger pipe will show a few extra ponies but at a large loss of torque throughout the usable rpm range. I will take the usable torque please!
I'd tend to agree with that. At least on smaller cubes like the 306 you mentioned.
Even on larger cubes with the same ex port I kinda wonder if bigger tubes would help all the time. Like maybe optimum tube diameter is as much connected to the ex port as it is to cubes.

I like to test with a pipe on ex too. It raises speed in the port and to me that's the best way to test. Try to see if there is a problem.

I still remember back in 1982 or so going down from 1 7/8 tube to 1 3/4 tubes on my Camaro and the smaller tubes were about 1/10 th faster in 1/8 mile, even though the bigger ones flowed more on the bench. 355 cube with 5500 stall. Kinda one of my first bigger isn't better moments.

What was it your sorry for ?

Randy

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 1:08 pm
by Erland Cox
It is an interesting question as the flow bench responds to the outlet area of the pipe and the diffusion will change the flow.
Something to think about.

Erland

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 7:59 pm
by Carnut1
0828171738c.jpg
65 289 1.85" port outline drawing. Not thrilled with the ssr. Input welcome. Thanks, Charlie

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 8:02 pm
by Erland Cox
I would try to make the SSR a constant radius from floor to seat.
It is usually possible without hitting water.

Erland

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 8:10 pm
by Carnut1
0828171738.jpg
65 289 1.6" exhaust drawing profile. Slightly smaller bowl and lower roof than first design. Input welcome. Thanks, Charlie

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 8:29 pm
by Carnut1
Resized_20170704_100630.jpeg
Carnut1 wrote:0828171738c.jpg65 289 1.85" port outline drawing. Not thrilled with the ssr. Input welcome. Thanks, Charlie
Interesting to compare with cutaway.

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 11:00 pm
by randy331
RevTheory wrote:Don't take the bait. You know where this is headed and why.
Pretty sad post .

Randy

Re: Ported Ford 289 heads with port energy discussion

Posted: Mon Aug 28, 2017 11:37 pm
by cgarb
[/quote]Interesting to compare with cutaway.[/quote]

Why Ford Motor Company must you put so much cooling water around the SSR on a 289 head?...lol. I'm not sure why the OEM's don't think about head porters more and cast some meat in these heads to work with. The grass is always greener on the other side and the air always wants to flow where there is no material to grind.

Re: Ported Ford 289 heads with port energy discussion

Posted: Tue Aug 29, 2017 6:29 am
by BILL-C
Anyone change the shape of the exhaust port exit to work better with headers that take a sharp downturn?

Re: Ported Ford 289 heads with port energy discussion

Posted: Tue Aug 29, 2017 6:31 am
by mag2555
Here's a example of designing / reworking, or assessing what you have already off of Throat size.

Re: Ported Ford 289 heads with port energy discussion

Posted: Tue Aug 29, 2017 12:28 pm
by Carnut1
Sometimes the bench gives you tunnel vision. Just read how these little heads easily handle a set of gen1 bowties unported as far as airflow with a 30 cc smaller intake port! They may not be failures after all! Thanks, Charlie

Re: Ported Ford 289 heads with port energy discussion

Posted: Tue Aug 29, 2017 12:29 pm
by turbo2256b
cgarb wrote:
Interesting to compare with cutaway.[/quote]

Why Ford Motor Company must you put so much cooling water around the SSR on a 289 head?...lol. I'm not sure why the OEM's don't think about head porters more and cast some meat in these heads to work with. The grass is always greener on the other side and the air always wants to flow where there is no material to grind.[/quote]


In the mid 90s working at ford advance engine design (not sure about back in the 289 days) A designer came up to me asking about the water passages in a cylinder head. The answer he got not from me was water passages should be used to lessen the amount of metal which cost X amount per cu centimeter. This concept produced several head designs that wouldnt cool hot spots because the water flow would take the path of least resistance. They had to kinda rework the cores with like baffles to redirect the coolant flow.
One reason for smaller spark plug threads had to do with better coolant passages around them.
Also did a project baseed on what was called precision cooling were passages flow was kinda figured out like a complicated electrical circuit. It was dumped to some extent as it didnt do much to improve emissions. Casing also had issues as the passages in the block were below minimum thickness. There were fixes to that issue I explained to ford but they wouldn't go for it.

If you were to collect all the OEM SBF heads one would find lots of variations in port designs some flowing better than others out of the box.

Re: Ported Ford 289 heads with port energy discussion

Posted: Tue Aug 29, 2017 12:59 pm
by mag2555
When I know I am port a Exh side that will need sharp bent tubes off the flange I first head for getting the most flow gain by means of port width increases at a certain point around the short turn, and this still all hinges on how much lift is being used.