Another Porting Thread

[34blazer]

Hi all

Im going to dig into a set of 8445 heads soon, and need a little bit of guidance. First of all, im not going to buy champion irons, and any other expensive hardware. The set of heads I have seem to be in great shape, just need to upgrade the springs, that's about it as far as hardware. Also, I've ported a few other sets of heads so all the tools I need are in the tool chest. Now on to the specifics...

Pocket porting: What is a good size to open up the throats to? A few pros gave me a rule of thumb of 85% to 89% size of throat to valve size, but has anyone here found a good size for the stock size valves? I just don't want to open them too far and run into reversion problems.

Port size: Other than the bottleneck at the entry of the port, is there any reason to enlarge intake port any further? I was thinking of raising up the roof a little, but that's about it.

Profile: Some people choose to leave the finish in rough carbide finish, and it seems that Larry Meaux has found some horsepower in a rough finish as well. Just not sure how well it will work with a turbocharged application, and im thinking of only leaving the intake port with the rough profile.

link... http://hotrodenginetech.com/pipemax-creator-larry-meaux-on-race-engine-head-porting/

That's it for now...

 

[34blazer]

bump

 

[earlbrown]

Keep in mind his hammered finish is for wet ports. In his own words the power seemed to come from keeping fuel in suspension instead of letting it blob up on the port walls. That doesn't apply to our plenums and intakes.

On the bowls, you'll see just how horrible they are with a big ass ring of iron choking the throat. Since you're there, I'd open them up to match a set of Ferrea stainless O/S valves, lower the guides and cut the exhausts for seals. Bowl port the intakes and do the same on the exhausts with a tapered bowl cutter. Clean up any oddball bumps and casting flash in the ports, polish the combustion chamber about 80%, machine the deck and call it a day. After the heads are on, set the intake in place, start the bolts and shove it to the rear as far as it'll go. Scribe the head ports to the intake and knock off anything hanging in the way. (you'll notice 6 stupid little lips on the leading edge of all the ports). That way when you put the intake back, you can use the 'shove' method and not have to worry about pinning it and whatnot.

These aren't N/A engines. Obsessing about every little nuance won't really gain you a thing. Once the turbo gets on the pipe, it'll blow right by any thing small.

 

[The Radius Kid]

Earl is right about most of this except for one thing IMO.
These ports are wet flow .... at least the lower section.
Only GDI engines run dry flow ports and they tend to have their own problems such as Carbon build up on the valve stems and back faces....no fuel wash.
The throat is one of the large areas of gains to be had as far as flow goes.
You also need to remember that the port walls aren't real thick either.
I always though some reshaping of the chambers in these Iron heads wouldn't hurt either.

 

[larrym]

Pay attention raising the roof.......

 

[34blazer]

How much can the bowls be opened up before encountering the water jacket? Im going to be conservative with any port work, ive been studying the cut aways at the .org and there isnt much room to play with.

Earl, when you suggest lowering the guides, are you talking about shortening them close to the roof of the port? I was going to bring the exhaust guide almost flush with the roof of the port

Any measurements will also help as I intend to make a couple of templates to keep things somewhat uniform.


Thanks!

 

[34blazer]

Here are a few pics from a SBF E7 head with the exhaust guide cut flush with the roof, and a chevy 2.8/3.4 iron head. This is what I intend to accomplish with the 8445 heads.

 

[earlbrown]

I'm talking about topping the guides on the spring side while you're there cutting the exhausts for seals. That way if you ever wanted to kill your bottom end and gas mileage with a big ass cam and hi-ratio rockers, you won't smack the retainer into them.

 

[34blazer]

I'm talking about topping the guides on the spring side while you're there cutting the exhausts for seals. That way if you ever wanted to kill your bottom end and gas mileage with a big ass cam and hi-ratio rockers, you won't smack the retainer into them.

Oh, yes, standard with these. I can cut the guides for a .500" Viton seal? Pretty sure that's what I used for the 2.8 heads years ago...

Thanks!

 

[34blazer]

Started on one head so far, pocket porting is 90% and ports have been deburred and somewhat smoothed. Have a lot going on right now so I may not have enough time to gasket match, but this will be a fairly large improvement. Just need to sand smooth, and touch up.

Pics

 

[34blazer]

Only had about 30 minutes to sneak out into the garage, so I started to sand the bowls with some 80 grit and decided to move on to the chamber. Stepped up to 180 grit and then to a crossbuff/WD40.

 

[34blazer]

Bowls sanded, started working on the ports. Going to leave the intake with an 80 grit finish.

 

[BOP4ever]

Nice work !!!

 

[34blazer]

Need to find cutters for the guide to cut it down lengthwise and widthwise for posi seals, sources for the cutters at a good price? One head almost done....

 

[ek02]

Decide what diameter seals you are going to use and then check out Comp Cams catalog. They have what you need and you can get them from Jeg's or Summit. I use 1/2" Viton seals and the 1/2" cutter (4715) and the 11/32" arbor (4732). They will cost you about 85.00 for both pieces. There may be cheaper cutters and arbors around.

 

[slamming 6]

Hi all

Im going to dig into a set of 8445 heads soon, and need a little bit of guidance. First of all, im not going to buy champion irons, and any other expensive hardware. The set of heads I have seem to be in great shape, just need to upgrade the springs, that's about it as far as hardware. Also, I've ported a few other sets of heads so all the tools I need are in the tool chest. Now on to the specifics...

Pocket porting: What is a good size to open up the throats to? A few pros gave me a rule of thumb of 85% to 89% size of throat to valve size, but has anyone here found a good size for the stock size valves? I just don't want to open them too far and run into reversion problems.

Port size: Other than the bottleneck at the entry of the port, is there any reason to enlarge intake port any further? I was thinking of raising up the roof a little, but that's about it.

Profile: Some people choose to leave the finish in rough carbide finish, and it seems that Larry Meaux has found some horsepower in a rough finish as well. Just not sure how well it will work with a turbocharged application, and im thinking of only leaving the intake port with the rough profile.

link... http://hotrodenginetech.com/pipemax-creator-larry-meaux-on-race-engine-head-porting/

That's it for now...

You will get more from the roof so you are right with that just pay close attention to the consistency of the shape of the ports.

 

[34blazer]

You will get more from the roof so you are right with that just pay close attention to the consistency of the shape of the ports.

I didn't do much(if any) port re-shaping, just what is shown in the pictures. There isn't much real estate to raise the top of the port to make a big difference, well, not without spending a bunch of time measuring with calipers and blending. I just don't have the time to spend 40-50 hours porting anymore, not with having a family and a hectic work schedule, there's about 5 hours total invested in one cylinder head right now, and it took almost two months to get this far. I could spend 40-50 hours doing side work and buy a set of nice CNC heads. This should still be a big improvement in flow, though. Still need to cut the guides too.

EK02, thanks. The comp cutters and arbor is what I will be buying, just need to sell these wilwood rear brakes first.

 

[turbofabricator]

The finished intake port you show needs the right side of the port wall straightened out. If you look at the picture you can see it narrows where the head bolt hole is. There is a fair amount of material in that area. If you go too far and find the head bolt hole.........don't panic....just ream up 1/64" and epoxy a brass tube in there. I usually only break through if I am doing a "max" port job. In that case I install pushrod tubes, too. I also use the 1200 Felpro gasket. Turbo engines love port volume if they are mostly track cars. I remove the entire exhaust guide out of the port. Widen the intake SSR but be careful as there is water under that there hump. Just remove 80% and smooth it out. The back side of the intake guide boss needs a big radius behind the valve guide. Search some of my posts on porting the Buick V6 heads. There are proven mods that do not show on the bench but do at the track.

 

[turbofabricator]

I need to add.........you are doing a good job. Tool control is very difficult, especially if you are not grinding often. Extended shank stones do a great job of finishing port work. Faster than sanding rolls. Be safe and wear hearing, eye, and lung protection when grinding on heads, especially iron heads.

 

[34blazer]

I see what you are talking about, unfortunately, that's is going to be the finished product if I ever have a chance to get these heads on by the end of winter. The back side of the intake guide has been tear-dropped to help keep turbulence to a minimum, actually, most of the time was spent on the pocket porting. Had to free hand the CC, didn't knick the seat on this seat so far, knock on wood.