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SwiftTech
01-22-2006, 09:14 PM
Just wanted to throw up a few pics for you all to look at. This is a spare swirl head that I had laying around. I decided to do a little port work. Both sides are gasket matched. The intake was left rough but the exhaust was polished to a near mirror finish. After I finished with the fine cross buff I hand polished with some wenol just for kicks. On the cyl head I decided to get a little daring. I deshrouded the valves and reshaped the combustion chamber more into a heart shape. I folled that by polishing the same as the exhaust runner. Feel free to comment, be it good or bad. I plan to flow the head when I'm done, hopefully with a friends flowbench when he gets it built.

zshadow
01-22-2006, 10:00 PM
so fresh and so clean clean!

it looks fairly good, you might want to get the intake part smooth (IMO), for when u put the gasket on it seals nice. the porting is a plus, but only if your going to use it, and put it to good use (going by what other people say)

when i started porting i asked people on td.com if it would be worth it, considering im only running a 87 t2 swapped 2.2. it didnt really do much.

according to some research the head flows enough air in/out up to around 20 psi.

but hey it looks good, and its super clean! :)

~Kevin

cordes
01-22-2006, 10:02 PM
Looks nice, but I will leave the technical comments to the experienced guys. :nod:

SwiftTech
01-22-2006, 10:56 PM
Thanks for the kind words guys. Those spots you see on the manifold surface are from the old gasket and will come off pretty easily. I plan to have the head resurfaced and a valve job done after all the work is done. Mabey I'll have them true the manifold surface too.

turbovanmanČ
01-23-2006, 01:14 AM
Looks good. Remember though, when you modify the chamber like that, your lowering compression ratio, :thumb:

I wouldn't worry too much about smoothing out the intake ports, they say roughness is good for turbulence.

87glhs232
01-23-2006, 01:53 AM
I wouldn't worry too much about smoothing out the intake ports, they say roughness is good for turbulence.

Yep. The only benefit to be had with a really smooth port is on the exhaust side...it gives less purchase for carbon built up.

2.216VTurbo
01-23-2006, 10:25 AM
Looks good so far, though I prefer to unshroud at the 'sides' of the valves instead of the tops. Don't think there is any problem with your way though. Have another look at the bowl are in the exhaust throats. Are all those ridges gone? There will be a slight one left at the base of the turn (the side opposite where you unshrouded) because if you take it all the way out you will be adding too much turn back there. You'll see what I mean. Them go back to the throat area where bowl transitions to port and make the ports WIDER there. As you are looking down the throat, head is like you have it in the picture, you want to take off material at the 1,2,3 oclock position on the right and the 9,10,11 oclock position on the left. Those walls and follow that into the ports themselves for a smooth transition. I will give up compression for flow every time:thumb: but you don't want to take out material just to take it.

The Pope
01-23-2006, 12:12 PM
http://boostedmopar.com/forums/showthread.php?t=451

All the flow is in the bowl, at the pinch point. Look in your intake and look at how large the opening is at the gasket and look how big it is at the guide. The open area at the valve is tiny. At the gasket it looked fine. Use a caliper to measure depth to make the 1/4" cutt in the roof of the port equal. The exhaust gets an 1/8". As is you gained about 10 CFM from polishing, should be about 155 CFM and now equal to a stock 2 piece for flow and more than what a 1 piece flows:thumb: Take the caliper and scribe a curve in the combustion chamber around your valves between 1/8" - 1/4", I do a 1/4" with big valves. 1/8"-3/16" is fine for a stock valve, the problem isn't as bad. Then useing the head gasket mark the diameter of the gasket. You will cut out to the lines and make an angle right to the seat. Pretty easy, then polish it, there is allot of gain in the combustion chambers. Look at my porting section for some ideas

Rob Walsh

86 GLHS 76
89 CSX 187
84 DC Shelby Rampage
86 goverment issue turbo Reliant wagon
70 Challenger R/T SE
72 Challenger Rally
93 Cummins 4x4 club LE
head porting
http://pnw-sdac.org/gallery/view_album.php?set_albumName=mods
the cars
http://pnw-sdac.org/gallery/view_album.php?set_albumName=album16

Clay
01-23-2006, 12:36 PM
I wouldn't worry too much about smoothing out the intake ports, they say roughness is good for turbulence.

thats true for carb cars, but with fuel injection cars it doesn't matter. Fuel atomazation is taken care of by the injectors, not by the fuel/air mix flowing through the manifold/head like it would on a carb car.

clay

2.216VTurbo
01-23-2006, 12:51 PM
Wow, nice hand work Rob:thumb:

I didn't realize the intake port roof could be raised that much, that much room and no H2O jacket eh? I'll spend a little more time there on my next SOHC head.

Not saying that I know what the best intake vs exhaust flow 'ratio' is, but there is a bunch of theory out there that says to make sure the exhaust numbers stay in line with what the intake can do. Are you getting way ahead on intake numbers with a head like the one in your pics?

I have to use restraint on the DOHC Masi heads, the exhaust will outflow the intake with relatively little effort, and all the experts agree that scenario is less than optimal:o

Nice Ex manifold too, I hate working with Iron:(

turbovanmanČ
01-23-2006, 01:30 PM
thats true for carb cars, but with fuel injection cars it doesn't matter. Fuel atomazation is taken care of by the injectors, not by the fuel/air mix flowing through the manifold/head like it would on a carb car.

clay

I knew someone would say that. Granted theres no fuel in the air but they say you still want some turbulence in the air to help carry the fuel where the fuel meets the air and help the air swirl into the chamber, :eyebrows:

The Pope
01-23-2006, 01:45 PM
I didn't realize the intake port roof could be raised that much, that much room and no H2O jacket eh? I'll spend a little more time there on my next SOHC head.

Not saying that I know what the best intake vs exhaust flow 'ratio' is, but there is a bunch of theory out there that says to make sure the exhaust numbers stay in line with what the intake can do. Are you getting way ahead on intake numbers with a head like the one in your pics?

Nice Ex manifold too, I hate working with Iron:(

The water jacket is near 3/8" at the pinch point, where most is removed. It is a matter of making the port the same size all the way to the valve, not making one end bigger than the other. The exhaust is a different story. Most use a log manifold and headers don't fit well. The TBI header works well but flows low volume. It all amounts to cylinder pressure for more HP on a 8v engine. It is good to make more exhaust flow, mine does, but the battle in the combustion chamber during overlap is where the power is. Cram allot more in with allot more intake flow and you'll get more power. There is a wash or exhaust and freash air and fuel in the combustion chamber from overlap, the bigger intake makes for the ratio of freash air and fuel higher. I've been broke for a couple months up here where it snows. Soon I'll have new valves in the head and be getting some good testing. Then people can see one way or another. If the head is good enough it can be copied with a CNC machine as it doesn't have matterial added to it. But big valve heads are allot more money. Valve cost is high, new seats, then some serious cutting. A stock valve head can be opened up allot and see a gain. The jump in flow between this head and a stock valve head with the same tricks is narrow, the jump in price is big. My self I charge $500 more for a big valve head so nearly twice the cost for a marginal increase. I was thinking about just adding big intake valves and running stock exhaust valves. You go up 4mm in intake valve, a big jump, the exhaust goes up 1.5mm? I debate whether or not it is worth the $45 a piece for custom exhaust valves:(

Clay
01-23-2006, 01:59 PM
I knew someone would say that. Granted theres no fuel in the air but they say you still want some turbulence in the air to help carry the fuel where the fuel meets the air and help the air swirl into the chamber, :eyebrows:

Yeah, but by that time the air is being pushed/drawn into the combustion chamber :eyebrows: Thats the big thing about turbo engines, there is alot of shoving going on in front of the intake valve.

we could probalby go back and forth on this forever Im sure. :p

The Pope
01-23-2006, 02:21 PM
Yeah, but by that time the air is being pushed/drawn into the combustion chamber :eyebrows: Thats the big thing about turbo engines, there is alot of shoving going on in front of the intake valve.

we could probalby go back and forth on this forever Im sure. :p

sure 10 PSI of intake pressure and 65 PSI of exhaust pressure and both valves open at the same time,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,:thumb:

SwiftTech
01-23-2006, 03:48 PM
Most use a log manifold and headers don't fit well. The TBI header works well but flows low volume.

I thought the tbi outflowed all other when chris tested them though? I will be using the tbi header for this.


Stock unported TII Exhaust manifold- 325
Stock Ported TII Exhaust Manifold- 335 (+3%)
Alabama Man Header- 355 (+9%)
TU Hybrid Header- 399.6 (+23%)
TBI Header- 412 (+27%)