disc0monkey

iTrader: (10)

people have been doing this for longer than you and me; imo this is what hotrodding is. your right, there is a limit to how extreme you can go without a flowbench but thats not what this threads about.

how much difference are you going to see just by doing what he did? doesnt cyl 7 and 8 flow more than the others bc of the intake? wheres the problem there?

Marcello7x

iTrader: (10)

I feel looks can be deceiving, i run my fingers over the ports and determine that way. That way it also helps me visualize the flow.

Those bits do take a while, but i rather take my time. Almost done with the first head and ill put money down that they would easily stack up to aftermarket heads if i got a galve job.

pwrtrip75

iTrader: (8)

I use the bit as a gauge. The width of it is how much i went down around the bowl, exactly that, and then just smoothed it up and blended it. I didnt actually dig down, just down far enough where the bit touched the bottom, and doing so it opened the sides up enough.






Same with the exhaust, I didnt actually remove material to reshape the walls... you can see the factory casting line all the way around. I just smoothed the bowls and around the guides. Everything was then sand/polished with 80 grit after this to smooth it a little and thats it.
All mine i would say are very close to each other....VERY.

gtotoocool1

iTrader: (6)

are you going to get any flow #s?would be interesting to see what the results are.

Marcello7x

iTrader: (10)

I took out a bit more material. Removed all the casting lines and evenly removed all the material around the elsewhere. Only thing i didnt touch was the short side, i just cleaned off the casting and blended the walls down to it. Im starting to prefer the bits removing material slowly. Its actually smooth to tje point i will barely need the sanding rolls.

disc0monkey

iTrader: (10)

marcello those bits we used i feel get smooth enough not to require sanding rolls for the intake ports.

next time i will start by taking the big chunks out wit pwrtrps bits, then move to the slower carbide i used before, then for the exhaust polish with sanding rolls.

Marcello7x

iTrader: (10)

Yes

I will since my plans changed as of yesterday. I decided to sell my lm7 and get a 6.0. I had planned a turbo 5.3, then drove it stock and lit up the tires too easily, so i dropped the turbo idea and go na. My goal was 400rwhp. Buy all the parts i accumulated were a little overkill. So either sell my parts or my motor, and i really rather have a 6.0. I decided to throw in these heads for an extra 100 for anyone that buys the motor. If i sell the motor w/o them they will be flow tested and sold.

Solid motor if anyone is interested, only 56k.

disc0monkey

iTrader: (10)

are you gonna do this to the 6.0l heads?

Marcello7x

iTrader: (10)

Yea i agree completely. At first i thought it was rough, then after i finished my first full exhaust port i realized it doesn't need much sanding at all.


Im sure i will at some point. Thats if i can sell my motor and recoup some of that money, or if someone wants to buy these heads for some decent chunk of change. Im open to offers.

The only reason im working on these now, is because my car is in a carport and its way too cold out to work on it and i need something to keep me busy.

To be completely honest i think its really relaxing. Im thinking its not something to bad to do on the side for some spare cash to throw at my hotrod. I expected to royally screw this set up, but its coming out great. Wish i could have done a before and after dyno just to see how i did. Flow numbers is one thing, you can just hog out tons of material and get high flow numbers, but to actually get an increase in power is another.

Mart00SS

iTrader: (19)

Its not as round as that picture makes it look. Thats a picture from the heads I ported. Here is another picture of the same port from the intake side.

disc0monkey

iTrader: (10)

yeah thats what mine looked like and general cncd heads for the most part.

fwiw this is exact opposite of what the old pontiac guys do, they leave that area you thinned out to take the air around the valveguide very wide to send that stream to the valve. thats what i meant by that. im pretty sure none of the old stuff is relative anyway lol.

Marcello7x

iTrader: (10)

Second time someone has brought up old pontiac methods. I read something on another forum a couple of weeks ago. I know most of the old stuff doesn't apply but there may be something to their tribal knowledge that we could benefit from, even if its just that their method doens't work as well

garygnu

buy a 5.3 head for cheap for a practice head.get a good pic of head cross section, so not cut into a coolant passage.

Marcello7x

iTrader: (10)

I thought about junking a head just to see how much material is really there. But with a 5.3l head, the vj becomes the restriction, and even just removing a small amount of material is an improvement.

My next set my be either another 862, or a 243 if i can get my hands on a set for a fair price.

Marcello7x

iTrader: (10)

My longer bits came in yesterday, along with my sanding rolls. Should be finishing up this weekend if all goes well.

Marcello7x

iTrader: (10)

can this much material be taken off stock castings?

98mysticZ

iTrader: (11)

ttt... subscribing... i am cleaning up my ported 317's and they didnt even touch the floor/short side right? what is the reasoning in this.. just very odd...

GuitsBoy

iTrader: (4)

In order to keep the carbide from loading up with aluminum, spray it, as well as the port walls with WD40. It will make a big difference.

A.R. Shale Targa

iTrader: (2)

Air flows most efficiently in a straight unrestricted line and according to an old
article I read about Ken Sperling(sp) spiraling like a cyclone through round
shapes....That being said a wedge-design head's worst transition is the tight
bend @ the shortside. If you can picture why for years cylinder head gurus
have been raising the intake port roof AND epoxy filling the floor it is to
straighten the tight transition from a horizontal flow path to vertical past the
valve. Many kick *** heads even cant the floor as it approaches the short
side to promote swirl (again to simulate a smoother path @ the back of the
intake valve). Lastly as the intake valve opens in a wedge head the air
coming past the valve @ or near the short side happens to be positioned near
the middle of the cylinder(bore) which is ultimately what you're filling and we
know air flow like inertia flows faster in the middle(center)...or so I'm told

98mysticZ

iTrader: (11)

also are yall cleaning these ports up with a 120 grit flap roll after? just wondering how yall are getting the ports to look so uniformed with the sanding