[UR2L8]

Here are some pictures of a head before and after porting.These heads are going on a 400 with 236 in. and 244 ex. @.050 .538 lift in. .550 lift ex. with a 4 spd. RPM limit of 6500.


All new pictures added as of 12-25-2001. Includining pictures of the short turn radious, I would like advice on the short turn radious and exhaust ports especially. where can I get more performance out of these heads?
http://communities.msn.com/79superch...oto&PhotoID=15
click next to view ported head and prev to veiw unported head.

[This message has been edited by martin (edited 12-25-2001).]

[UR2L8]

Here are some pictures of a head before and after porting.These heads are going on a 400 with 236 in. and 244 ex. @.050 .538 lift in. .550 lift ex. with a 4 spd. RPM limit of 6500.


All new pictures added as of 12-25-2001. Includining pictures of the short turn radious, I would like advice on the short turn radious and exhaust ports especially. where can I get more performance out of these heads?
http://communities.msn.com/79superch...oto&PhotoID=15
click next to view ported head and prev to veiw unported head.

[This message has been edited by martin (edited 12-25-2001).]

[larry davis]

It's hard to tell w/ the shadowing & grainy appearance of the furnished photos.
I would recommend shining a flourescent work light into the intake ports, exhaust ports, & combustion chambers from the the opposite side of what your photographing. Try this w/ & w/o flash for best results.

[Ockhams Electric Razor]

What Larry said. It's hard to tell exactly but it looks like you could cut back the pushrod ski jumps much further then what they are. Also, there is a lot of sculpting you could do around the guides. I'm no expert, though, not even close, just my .02. The throats look fairly large, how big did you cut them? Did you touch the short turn at all, at least widen it to fit the new throat size and maintain that radius and "waterfall" effect?

[UR2L8]

I tried to use a light in the port but the shine from the light is too bright, the ports look white. Same with the flash.It is a cheap camera. I didn't open the throat much I tried to just smooth it from the widest point to the narrowest, opening the narrowest just a little. I didn't grind on the short turn at all, I just ran over it with an 80 grit roll untill I took all of the soot off. I just tried to flaten out, then blend the bump in front of the intake valve and behind the exaust valve (The exhaust valve bump seems huge) I knocked down the push rod bulge by .040 I tried to get the port to look as rectangular as posible. The heads are 670's and there is a hole in the exhaust valve bulge that seems to go through the head to the top of the head. The holes are caped. Does anyone know why the holes are there? Please give your opinion freely as I took these pictures and made these posts to learn. Thanks for your experience.

[This message has been edited by martin (edited 12-23-2001).]

[Will]

Definitely need better pictures to get an idea of what's going on in those ports, but from your description it sounds like you stayed conservative, which is good.

Even if you take really good pictures, the 2-dimensional nature of a photo and the inability to look at the port from any angle other than what the picture was taken at makes assessing what's really going on in there difficult.

I took quite a few pictures of the ports in my old 400 heads and in the 6X heads I did for a friend and you can tell they've been ground on and opened up, but you can't really see how much or what the short side looks like, etc.

The holes in the exhaust bulge that go to the top of the head are for AIR, which most engines weren't equipped with (California only in '67 I think), thus yours are capped. My '67 #061s have that same thing. What's interesting is that those holes are all interconnected by a gallery that runs the entire length of the head just above the exhaust ports. Freaked me out when we were vacuum testing the exhaust ports on my heads, we couldn't get any seal until we plugged up those holes.

[Larry Navarro]

#16 D-ports...277cfm@.550", widened intakes with pushrod tubes installed to match SD/RA4 gasket. http://community.webshots.com/photo/...7542cYrLThxCvm http://community.webshots.com/photo/...3571JEfGhWKTmk http://community.webshots.com/photo/...7398SGtCnVzVgV http://community.webshots.com/photo/...7658DMoINsYSpy



[This message has been edited by Larry Navarro (edited 12-24-2001).]

[larry davis]

Larry N, nice lookin' & consistant radius' along the intake corners.
What # of heads were those of the original poster? Try turning the light, so it doesn't directly shine in the port if it's too bright.

[Larry Navarro]

i believe martins heads are 670's.

[Tim Corcoran]

Larry,

I noticed that you went through the pushrod holes and inserted brass tubes. It is not necessary to go to this extreme to get the numbers you have. This is not meant as a crticism, just sharing of information. Most of your increase air flow comes from the bowl work and properly shaping of the short turn radius. The runner work is only of minimal significance. In the runner you want to try to maintain consistent shape and size throughout the run, concentrate on smoothing out the turns and not going for maximum size. You can remove some of the pushrod bulge but you don't have to go crazy to get the numbers. The short turn radius should be pretty much just as wide as your bowl and smooth out this radius to make a more gentle turn. It is very difficult to work the short turn radius, as it is difficult to see and to get a roll or cutter in there. This is where the flow number are made though. Try to maintain a smooth and getle turn, you have to go pretty much by feel. My 16's flow 190 cfm @28 on the intakes and the push rod bulge did not cut through. I did not port these heads.

Tim Corcoran

------------------
65 LeMans 11.13@120

[larry davis]

Tim, is that 190 cfm right?

That's pretty low.

[Bruce Meyer]

I think Timmy has dyslexia. Ive seen his heads and the flow sheets. His heads flow 290 cfm @28". They do not have pushrod tubes.

[UR2L8]

Larry N.Those Pictures are great. I was hoping someone had something like that. Those pictures helped me, I see I need to do some more blending and "sculpting". Does anyone have pictures of the exhaust port and short turn radious? I haven't really done anything to the short turn (minor blending) because I have read so much about the possiblity of hurting flow.

[Half-Inch Stud]

martin, I looked, tried to think, but nothings happening.

My first thoughts were on the valveguides being long enough to support the valves. I just cannot tell from the picts.

My second thoughts were on the center exhaust ports having a straight shot. Tough to do with the bolt boss on the roof. Pictures don't allow the 3D imagination to flow.

Overall, I guess they are OK.

[Half-Inch Stud]

Larry,

for some reason, your photos are far more clear to interpret. I see an excellent Intake shot...exactly what I strive for. My best attempt was the 5C head..achieved an Intake shot like you 16's have. My 16's didn't get anywhere near you shot.

My 48's are almost that good.

Misus's Ram IVs are probably the best iron I've ever seen. Sheesh.

[Larry Navarro]

HIS...glad you like them. i just need to get a bottom end together to utilize them.
added a shot of the chambers to my first post.

[This message has been edited by Larry Navarro (edited 12-24-2001).]

[UR2L8]

I took more picture that can be seen in the origional post check them out, hope they are better. Thanks Martin

[larry davis]

Martin, your new pics. are better.

Looks like your on the right road.
I am concerned that your hitting the valve seats too much. Not knowing if they have been cut before or not, remember that the more damage done to the seats , the deeper they will have to be machined. If it's too deep, they'll have to be replaced; as it makes getting the proper run out impossible.
My other concern is that the intake ports appear to be rough or uneven around the edges. Refer to Larry N's photos in this same thread. See how he has layed his out prior to grinding? You need to do the same to establish the outer perimeter, so you can blend the runner into the actual outer port dimension. See how his sides & top & bottom are parrallel & perpindicular? With consistant radius' on the corners? That's what your after. If you don't have machinists dye to use for the layout a permenent marker works fine. Just use a scribe to dimensionally layout the ports or trace it out from a properly situated intake gasket of the same type you'll be using.

[UR2L8]

I hate my camera! It's quality stinks. I did not hit the seats at all. (after looking at the pictures again it does look like I did) I added a another picture of the ports with the scribes. The quality sucks, but I hope it helps. http://communities.msn.com/79superch...oto&PhotoID=21
I cleaned up the port entry on the intakes do they look beter?



[This message has been edited by martin (edited 12-25-2001).]

[Rocky Rotella]

What's the second hole in the exhaust port in the pic of the chamber? Is that the rocker stud boss breaking through? I'm guessing so since it's in line with the valve guide.

[This message has been edited by Rocky Rotella (edited 12-25-2001).]