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7MM Head
https://slantsix.org/forum/viewtopic.php?t=56342		 Page 3 of 7
Author:  DKD [ Thu Oct 09, 2014 7:06 am ]
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Re flow benches. I remember when first got my flow bench up and running. That was for many of us a heartbreaking experience. Many of the things we had been taught or led to think were good were bad. The gains come little by little and losses are huge and come with a couple of grinds in the wrong place. I tested a lot of stuff. Professionally ported heads sold by DC. (That was a disappointing shock!)All the BB castings including 518s 286 346 452 big and small plug 906s Small block and Indy and Stg 6 aluminum. Learned an awful lot. And I learned the flow bench could care less about opinion. It gives the results. I learned to trust it and tried a lot of experiments to see if the result were valid or not. To date it never lied. After awhile you actually learn what to do (and what not to do) on your own. When I sold all my machine shop equipment my bench was included in the package deal. I have explored buying it back but so far without even a price being set so I let it be.
Back when we first went to unleaded gas the valve seat thing was a huge problem. It drove us nuts in the industry for awhile. But in a few years it became a none issue. I haven't seen a recessed valve seat for a long time now even when I visit my pals machine shop. I don't know exactly how many for sure but over the years that I ran my last shop I would have done hundreds of oversize valve installs in mopar heads during prep and all without seats. And without problems. Problems reflect on me so I didn't want any. They also cost you money and business. If I thought there was a risk here I would have done otherwise.
Author:  the_engineers [ Thu Oct 09, 2014 7:48 am ]
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As the problems went away, was that due to changes in gasoline content or technology changes in the heads you were working on?

My heads are from 1971, so they won't have any post-lead technical evolution to benefit from.

As for fuel, I still haven't ruled out running E-85. Overall, my goals for the motor are a simple 100 hp/L (flywheel). With a turbo and an otherwise mild motor, I'm projecting 18 lbs of boost to get me there...Things are going to get hot.
Author:  CNC-Dude [ Thu Oct 09, 2014 10:47 am ]
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The fuel issues of the early 70's literally happened overnight, so it took the industry totally by surprise. It took the oil and gas industry a little bit to figure out the no-lead and octane requirements to find a happy medium, as it did the automotive industry time to figure out modified tuning and timing changes needed to compensate. And from that day forward almost 40 years ago, technology and knowledge have also continued to improved. The hardened seats were only a precaution, not a requirement to solve the problem. Ford and Chevy didn't have to do it, they figured out the problem and went on their way 40 years ago.

Back then when your car was detonating and dieseling when you shut it off, what did people do about it....nothing, they kept driving it until it beat the seats out of it, instead of fixing the problem correctly with proper timing and tuning and maintenance. Installing hardened seats didn't fix the problem, it only fixed the results of the problem. Today, people are more hands on with these older cars and this just isn't a problem any longer, plus gas is much better than back then and its just harder to detonate an engine with alcohol in it. And again, Ford and GM have never had to do that with their engines, because they actually fixed the problem and not just the results of the problem. Engines are just more resistant to those issues than they were 40 years ago.

Occasionally today you will still see a flattened valve seat, but it is more from poor engine maintenance and lack of proper tuning than no-lead gas.
Author:  DKD [ Thu Oct 09, 2014 2:13 pm ]
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Well said. Nothing more need be added.
don
Author:  the_engineers [ Fri Oct 10, 2014 11:49 am ]
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Below are pics of the differences between stock and proposed pieces. After looking at the groove arrangement on the Navigator intake valve and Windstar exhaust, I think my best bet is to go 2.5L Ford valves across the board.

Springs:
Image

L to R: Stock, 3.8L Ford Windstar

Intake Valves:
Image

L to R: Stock, 2.5 Ford Ranger, 5.4 SOHC Lincoln Navigator

Exhaust Valves:
Image

L to R: Stock, 2.5 Ford Ranger, 3.8 Ford Windstar

I bought cheap valves for mock-up. Once we've got a clear plan, I'll either have these back cut or find better pieces.

It's hard to see from the pics, but the 7mm valves are almost "dainty" by comparison. The weight difference is insane.
Author:  emsvitil [ Fri Oct 10, 2014 8:27 pm ]
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Are you going use stainless?

I did some researching on valve seat recession, and one of the reasons given for it was micro-welding of similar metals.

I think this is where stainless (or titanium) valves help. The valves don't want to weld to the head.............
Author:  emsvitil [ Sat Oct 11, 2014 2:20 am ]
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http://www.custom-car.us/cylinder-head/valve-train.aspx
Author:  Dart270 [ Sat Oct 11, 2014 5:56 am ]
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Nice pics, Brooks. For the navigator valves , the long stem above the valve lock worries me concerning geometry of the spring and binding.

Great thought/info, Ed.

Lou
Author:  DKD [ Sat Oct 11, 2014 6:48 am ]
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The 7mm valves look good. You are thinking ahead of the curve. Go for it.
don
Author:  the_engineers [ Sat Oct 11, 2014 3:37 pm ]
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Thanks Lou, All.

Interestingly enough, if I get down to a 1.8 - 1.9" valve spring height, virtually any LS spring will work. Lots of possibilities then...
Author:  Dart270 [ Sun Oct 12, 2014 6:26 am ]
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Just be careful of coil bind or crashing the retainer into the guide boss at full lift. Otherwise, I'm curious as to how this will work!

Lou
Author:  CNC-Dude [ Wed Oct 15, 2014 12:01 am ]
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Here's the valves i'll be using for my 7MM conversion.
Image
Author:  Rick Covalt [ Wed Oct 15, 2014 3:33 am ]
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What are they from Scott? No lock grooves on them yet?
Author:  CNC-Dude [ Wed Oct 15, 2014 9:09 am ]
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Rick, these are race quality valve blanks, so they are pretty much universal at this point and can fit most any application. I'm not sure if you can see in the pic that well or not but they are also swirl polished. Once I am set on the length, I will cut the tip length and lock grooves in them to match my needs more precisely.
Author:  the_engineers [ Wed Oct 15, 2014 11:01 am ]
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What's the cost on blanks? I've reached out to 2.3 specialist about their stainless valves, but haven't heard back.
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