mike1111

this is for a 1984 crossfire with ported intake manifold
low-cost simple flow bench. heads are summit/dart 165ss. I wanted to know if porting job did anything, it did. just comparing the manometer reading before and after porting. picture shows the lip left after valve job was done. made some covers to protect valve job during porting, there crude but they work. I bowl blended the lip and skinnied up the valve guides and removed casting imperfections. haven't de-shrouded the valves yet. need get some old valves for de-shrouding and make a cover to protect the head surface. Even the best can lose control of grinder and I'm a beginner, although I fabricated metal for over 40 years that included finishing with die grinders, so I'm very familiar with die grinders. maybe de-shrouding will give low lift gains.
after I take the intake and exhaust manifold off car, will then test them on the head. test those diffusers for sure.
this is fun stuff

Highwayman9011

So your a Super Genius!!! Cool job building the bench !! It nice to see what you are doing actually works out when porting!!

mike1111

thanks . did a lot of reading and watching videos. david vizard books and so on. Its actually fun to me. It was nice to see gains for sure. It was just a bowl blend. the exhaust really needed it. very curious to see what ported intake manifold does

Highwayman9011

Keep it up and post it up. This is interesting post info,,

mike1111

will do as soon as I take manifold off

Tom400CFI

In for learning. LOVE IT!!

cv67

Boy are you in for an education!! lol
Heres some decent info for the DIY person
Youll find deshrouding isnt always needed....lots to learn youll dig it.

http://www.flowperformance.com/system.html

mike1111

I haven't made the ports bigger other than the bowl blend and slightly making the valve guides smaller. Pinch point stock, throat is on the smaller side. this is a very conservative port job. Eric Weingartner flowed one of these heads unported, intake @.5 lift 237cfm. Main reason for porting heads was the exhaust port. 138 cfm @.5 lift. a .0625" lip left after valve job was done. I think the heads will out flow intake manifold already or flow the same. have to test with intake manifold now. I'm not looking for big numbers. I have stock and ported intake manifold. going to compare them. did enlarge the intake manifold from1.39 CSA to 1.77 CSA. using csa and math, stock should flow 1.39x133=184 cfm and that is optimistic because of all the inconsistency in the port. Ported 1.77x133=235cfm. there's still enough material on manifold to get 2.1 csa. 2.1x133=279, don't need that. Looks like the work is now with the intake manifold. diffuser looks like a choke point, if it is, I'm going to make a step sleeve for the diffuser so it will flow more air and still diffuse mixture. not sure if I'm going to block off balance ports yet. hopefully this will translate to HP. if it doesn't that's life. never learn anything if ya don't try.

mike1111

been there and also
PTS Flowbench Forum - Index page (flowbenchtech.com)

cv67

Ah, PTS thats the one I was looking for,been yrs since Ive been on there. my mistake!

Shame one of the best areas for gains is a pain to get to and cant see it. The all important short turn
Have a similar mentality such as yourself..not about a max web hero flow# its about quality of flow, where it starts and gives up
Ea application is different. The "hogging out" look how big I got it mindset is decades old thinking.
Bet you know what can look impressive on a bench doesnt always work good once the engine is in the car.
Keep us posted always love reading about others projects.

mike1111

did a basic bowl blend on dart 165ss heads. modified crossfire intake manifold. welded on top of ports and welded round rod to runner entrance. blended the ridge left by valve job on heads. the exhaust ridge is pretty big. intake has a ridge mostly on left side if looking at these photos. exhaust got bigger gains.
intake manifold has more finish work to do. But it was good enough to test. cleanup work isn't going to make it flow better, it will just look better. Did flow each intake port and there all about the same flow. not sure if i'm going to block balance ports. could slot the top and drive in a piece of aluminum, then weld the top.
connected to dart heads the intake head combo flows 196 cfm at .425. At .500 its at least 200, but I'm not sure about that. using stock head to compare. Could be more. more testing to do.
exhaust tested about 180cfm at .500. its way more then the stock dart port 138cfm.
stock exhaust manifold flowed 125cfm @ .500. I cut the header tube at the collector where its pinched down and hammered the pipe out and grinded about an .125" out of the collector.it flowed about 155cfm after that. thats about max. the Id of the pipe is 1.325". should get headers.

Tom400CFI

Looks good. I like the radiused runner mouths.

mike1111

they actually worked to my surprise. tried putting clay radius on stock manifold, it did nothing. cutting back the runners must play into it working.

Tom400CFI

Interesting. Cutting 'em back would increase the available space for air to get over the adjacent runners to get to the mouths of the "sucking" runner(s). I guess?

84 4+3

I should get myself a real welder... looks good.

mike1111

its hard to weld. slower process because its dirty old casting. But doable.

84 4+3

Yeah. I had a friend TIG what was done on mine and he said it was one of the worst he's seen as far as dirty. I have a 160 amp MIG but I know that won't even touch the thing... I won't bother my friend with it again as for him to tell me it was bad, it was pretty bad.

mike1111

there is a little different technique welding old manifolds

mike1111

thought I was done with manifold, but after testing today, going to fill holes. test with and without tape over hole. without tape cfm drops. put vacuum on adjacent runner with no tape it drops a little more. going to drill a slot in from the top ,then weld a piece of aluminum in from the top. after that

Tom400CFI

I love how you sort of "wrapped" the runner pair mouths toward the TB's.