Y2K2LS1

I've done alot of reading with regard to DIY head porting for LS1's. Learned alot. Saw some good pics from people which helped me visualize how I am going to shape/blend the ports. There are just a few things i'm not completely clear on, because from what I have read and the pics I have seen, people have shaped things differently. I'd like to adress some of these things now.

Shaping around the valve guides

Is the basic idea to take material from the sides of the guide and leave a sharp peak? I have seen some people just take out material, but leave the shape of the casting around the guide the same, round. But most I have seen take material out on both sides leaving a sharp edge. How do the experts do it? What are your thoughts?


Swirl ramp

To take it out or not to? From what i've gathered it is there to create the turbulence necessary for low end torque. Is this right? Some take it out completely and have good peak results, some take about half of it out, and some leave it alone. After reading J-rod's timing thread, i'm wondering if the swirl ramp is necessary for proper high velocity in the combustion process to combat detonation. It could be there for a reason, to get the mixture to go to a certain area in the chamber? What do you guys think? Take it out or not? If some people take it out completely, there can't be a water passage under there right?

Blending seats

I've noticed on the heads i'm about to port, the area where the seat meets the casting is less than perfect. I just want to make sure I can blend the seat to the casting as long as I don't touch the part of the seat where the valve rests. Any tips on this? Should blend more agressively where the port floor rolls down into the seat (short side radius)?


The heads i'm working on are LS1 241 castings. I do not have a professional set of ported LS1 heads to look at, only the pics I find online, so it makes it difficult to visualize the right way to do it. Any advice or input is really appreciated!

Thanks

Lostpatrolman

iTrader: (3)

Here are a few pics of my felberracing heads. I have no idea how they flow yet, but here is what was done to them. Hopefully you will find some of it useful.


The seats seem to have blended, this one looks liek it was hit with a grinder though
The front of the valve guide was made into a sharp peak, I believe the rears should have been also.

Lostpatrolman

iTrader: (3)

Oh yeah, Where is the swirl ramp, the upper D area where the injector sits?

ChucksZ06

iTrader: (9)

My new patriots look pretty good.

Lostpatrolman

iTrader: (3)

umm... got any pics?

M6HuggerSS

here are some pics

M6HuggerSS

a few more...

M6HuggerSS

here are MY heads...

M6HuggerSS

hope those helped!

Slowhawk

iTrader: (12)

On the intake ports the floor has been ground down alot.I hope they pressure checked the heads.I've had 2 set's leak coolant from the ports being cutdown too far--hairline cracks.

M6HuggerSS

which pics are you refuring to?

Lostpatrolman

iTrader: (3)

Hugger, could you label the porter for each set of heads?

M6HuggerSS

these are mti's

M6HuggerSS

these are jantazer?

M6HuggerSS

i dont remember whos these were?

but they are awsome.

foff667

iTrader: (2)

[QUOTE=Lostpatrolman]Here are a few pics of my felberracing heads. I have no idea how they flow yet, but here is what was done to them. Hopefully you will find some of it useful.


The seats seem to have blended, this one looks liek it was hit with a grinder though
The front of the valve guide was made into a sharp peak, I believe the rears should have been also.

did they go all the way through to the stud on this pic?

Lostpatrolman

iTrader: (3)

lol, these are the ones I was wondering about. They look like no expense was spared.

Lostpatrolman

iTrader: (3)

[QUOTE=foff667]Yes, all the intake ports on those heads hit the rocker arm holes. Once the studs are installed, the remainder of the bolt sticking into the port will be ground down flush with the port. No big deal. Just have to make sure to put some sort of sealant on the threads so oil doesnt seep down the threads and find its way into the intake port.

leaftye

FWIW, here's a copy of the head porting links I've placed out here: http://forums.corvetteforum.com/showthread.php?t=984927

Head Porting:
Articles
Angling For Power
Bench Racing
Combustion Science and Theory
Compressions Ratio -vs- Compression Pressure
Standard Abrasives - DIY Cylinder Head Porting Guide
Do-It-Yourself Small-Block Cylinder Head Porting
Fire in the Hole-How combustion chamber design relates to engine performance
Go With the Flow Part I: Making Sense of Cylinder Head Flow Testing
Go With the Flow Part II: Making Sense of Cylinder Head Flow Testing
Head Porting at Home
Magnificent Quench
Quench Quest
Go With the Flow Part I: Making Sense of Cylinder Head Flow Testing
Go With the Flow Part II: Making Sense of Cylinder Head Flow Testing

Threads
Good books or articles on head porting???
Head Porting
Head Porting At Home
Head Porting Book?
Here are the head cross section pics
Home heads Porters Come In
Home porting on heads?
Pics of ported and polished heads
Porting At Home
Porting stock ls1 heads?
porting tips for LS1 heads
PP LS6 Style Head Review (flow, specs, comparison inside)
Who's ported their own heads?

itchygomey98

iTrader: (2)

If this is the first set you are porting and do not have access to a flowbench, here is what I would do.
1. Cut the rocker bosses - you'll go through here, but don't worry. Just use thread sealer on the rocker bolts.
2. Blend the exhaust guide to a point.
3. Cut the long side of the exhaust port so it's more of a straight shot. There is about .100 material here, so you have an idea of how much to take off.
4. Polish the exhaust port and the combustion chamber
5. Leave the intake swirl ramp. You could cause problems here without something to guage your success (a flowbench)
6. Blend the seats
7. Pay for some good valves and a valve job if needed.
This is just my personal opinion, but with this approach I think you will be pleased with your first set.