How am i doing? This is my first time porting heads so all sugestions are welcome!!

This pictured bowl is semi-done, im still shaping and stream-lining the valve guide boss and going to smooth out all the cutting with cartridge rolls.

These will be cut for 1.94 intake valves when i'm done.

I'm going to pick up 2 more cutters tonight hopefully. The one i've been using is a flame shape with a point and its dug in a few times. what i'm wanting is a round nose tree shaped cutter with a 6" shank and a ball shaped one.

a few questions for you pro's! ;

Did i open up the bowls too much?

Is the sort side radius cut down too much?

Can i safely shorten the valve guide boss?


These photos are all the same bowl.

 

2

 

3

 

Anybody??

 

Comments?

Sugestions?

Anyone?

Need some advice here

 

I would say good job, but i have never ported heads before. I hope they turn out good for you. I'd like to port mine to hold me over until I get the vortec heads put on. have to save $$

 

Looking good. It's not about how much can I take out, but instead how can I open these up and allow a smooth air flow. Keep going, I think you will be satisfied when you are done.

 

Looks like what i did to mine - not that I would know whether or not it's good - I had never done it before either! But the machine shop said it looked good when I was done, and the car has run for the last year, so it must be OK.

On the cutters - the 6 inch shank - BE CAREFUL WITH THIS ONE! I was using an 25,000 rpm electric grinder, with an RPM reducer, but let me tell you that when that sucker came out of the chuck at 15,000 rpm's, it really flew! It literally cut it's way through the woods and flew out across the neighborhood - I estimate about 6 houses away is where it landed - I never saw it again. I'm just happy my head (or the neighbor) wasn't in it's path!

 

k, first of all, I second camaronewbies thoughts, I had my 6" cutter go bent on me at 20k rpm or so, and the vibrations before I shut it off made my hands shaky for hours.... VERY BAD.
Don't use much pressure on it.


I'm sorry i'm not of much use here, as i'm a few weeks behind you, i'm still practicing on some 993 heads.... But I was going to ask the same question about the valve guide, as mine is still taller then that now.... Is there a limit as to how much you can shorten it? smooth it right out? bad idea?


There are some VERY knowledgeable people on this matter (no offense to anyone), and I really hope they chime in.... (F-bird, Sitting bull, etc.)


oh yea, did you get tapered cartridge rolls, or straight? what are your plans for the rocker studs?

 

Looks like a good start but you have a ways to go yet.
The pointed cutters are nut for doing the bowl. they are for doing the corner radii of the runners etc.

I use a blunt curved ended straight cylindrical shaped cutter for the whole bowl rework. You can and should open up the area between the port wall and guide boss on the common wall side a lot more. See how this wall is curved as it passes the cylinder head bolt hole. You want to create a flow path there by straightenin that wall and carving that side of the guide boss.

Get the garden hose out and flow some water thru the port and you'll see that the roof/ common wall area is a high flow area. Other than that the guide boss contouring looks good.
You don't need to shorten the guide boss too much either. remember that supports the valve.

Look at some other pic of aftermarket heads, even vortecs and you'll see how nice and open the bowl area is near the guide boss.

You only need one long shaft cutter for deep in the intake port. a oval shape or flame shape is best. Not a sharp point.
You don't need to run it a@ 20K rpm either.

 

The green arrows are the high air flow path that comes along the common wall and roof past the guide and swirls into the chamber twards the plug.
the red lines are where I'd cut some more.

Don't worry you really can't make these heads too big.
The only risky area is right where the wall curves past the bolt hole. You want to straighten out the wall there about 85%. 100% will get you into the bolt hole. use common sence.

 

The cutter pic F'Bird shows I used alot, in both a long shank and a short shank The long shanked one was the one that went flying - and I had to get another). It was the most useful overall for me.

Again - Just be careful! If I ever do it again - I'll find a football helmet to wear! And make the neighbors stay inside!

 

I finally got out to buy new cutters and they didnt have the one i wanted with the 6" shank. But i did pick up a short shaf double-cut radiused cylinder and it cuts very fast. almost too fast! i'm using a 25,000 RPM air die grinder so it can easily get out of hand.. What i done was wrapped a shop paper towl around the grinder, under the trigger making it harder to press down.

tonight i got 5 more bowls cut out real good. i done a rough cut, just to remove metal and i'm going to touch up when i get the porting kit with all the abrasives.

I'll get some more pics so you can see my progress. I opened up that high flow area more that you drew Fbird. The valve guide boss is slimmer and more streamlined as well. Thanks for your help and effort!!

Should i sqaure up where the floor meets the walls in the runners? Or give it rounded corners?

Does the short side radius look good? I feared i cut it down too much..

Sonix, the rocker studs will probably end up getting pinned..

thanks for the help everyone

Good news is these heads are being cut for 1.94 valves and getting new seats for "free" (getting block mantianced too).. cant beat that..its always nice when manchinist return favors!!

 

I have all of the intake bowls cut rough and i picked up a standard abrasives delux porting kit over the weekend at JEGs. they stopped carrying it for some reason, i got the last one.

I'll get some photos ASAP. They are shaping up nicely, that flow path between the valve guide and wall is over twice the size it is in that previous picture.

Could someone answer some questions for me? I'd really like to get the best out of my efforts here..

Should i sqaure up where the floor meets the walls in the runners? Or give it rounded corners?

Does the short side radius look good?

Any tips on getting the exhaust to really flow good?

Hopefully i'll be able to pick up the new valves, springs, locks and retainers this weekend. Would undercut valves be worth it since i'm replacing them all already??

 

damn website stopped emailing me when someone posted....


upload more pics, i'm dying to know more of what mine should look like at the end...

F-bird has recommended a 5/16" rat tail file in a drill, for elongating your pushrod slots, *and* for squaring up the port sides.

i'd say yes to the undercut valves. I can scan/upload something from vizard in his how to port SBC heads, about 7 different things done to valves, and what the result was.... one that I thought was neat was to chuck the valve in a drill, and use a stone in your die grinder to backcut the valve *manually*.... kinda scared me, but it seemed to provide good results...

 

Im done doing the bowl and port work, Im going to purchase a tapered abrasive kit and do the finishing touches on the chambers and exhuast sides.

Today I f'd up and slipped and hit a intake valve seat. I was going to install the heads with the stock valves and just lap them on my 305 engine untill I had a 350 shortblock built.

What will happen if I have a nicked seat? Bad things, major power losss... I guess I should have a valve job done on just one valve? Full valve job is $220 by me. And all guides are $132. Id rather just get these installed with stock valves now untill I feel like laying out more money. What shoudl I do?

 

If it is a real light nick then the valve should flatten it back out. Otherwise a valve job is in.

 

I thought you were getting new valve seats for free?

wait, this is a different member, WTF is going on???

 

Sonix i'll get some more pics soon. It only has to wait because my heads are a 20 minute drive away, at the garage. Soon enough though, hopefully i'll get out to work on them tonight.

I'm getting my machining done for "free" (not really free, just not costing money). cut for 1.94 intakes and 3 angle valve job, seats, tanking. He's even doing my block and crank for me too. All for some spare th350 parts.

 

What a deal!

 

its almost a steal, vrtc350. we'll see if he comes through!

Bad news though, our air compressor blew up, it smashed a piston and needs rebuilt now... bad timing! my uncle said the parts should be in, in 5-10 days.

more bad news, i forgot my camera out there last night.. lol.. sorry again.

Could someone answer these questions i've been asking?

Does the short side radius look good in the photos?

Any tips on getting the exhaust to really flow good?

 

I did the same thing, 1.94s and full porting on 416s. look at my website on the engine build up section for pics of my intake and exhaust ports. IMO this is a major waste of time porting beyond gasket matching on our cars, you have a greater chance of doing more harm then good, these heads flow well enough on their own. The 305 and tpi will only give you minimal gains even on a well built motor, we are talking 15HP tops.

 

these are going on a newly rebuilt 350 with XE268 cam, Performer RPM Qjet intake, Hedman hedders, and full 3" exhaust. Hopefully it will be pretty decent once its all together and running. As soon as my heads are done we'll see because its the only thing stopping me from putting it together.

Id like to get back out to the track once more this year before it closes to see how good it runs.

Could someone answer my questions??

Does the short side radius look good in the photos?

Any tips on getting the exhaust to really flow good?

 

FYI I just dropped a 350 with performer rpm intake in my 1992. Know now that this will NOT fit under a stock camaro hood, at least not with new ploy motor mounts. I've tried every dropped base air cleaner I can get my hands on, and nothing fits.

 

My Performer RPM fit under my hood with the 305 in there. I removed the hood insulation and put a drop based air cleaner on. fits fine, even some room to spare.

 

doom, that's Exactly what i'm doing (350, 268 cam, reworked 416 heads with 1.94/1.5 valves, headers, single 3" exhaust, same intake, etc...)
You HAVE to let me know how that works when you're done.


I think your short side radius looks good, you blended it into the area right below the valve seat. If it feels like a nice smooth radius, that's what you want. I'm not sure how much material you took out, or how much you should.

the exhaust: same thing as what you did for the intake
port it! do the same with the intake guide, etc.

 

From what little there is to be seen from the pix, it looks fine on the short side radius. Removing gobs of iron there is not what we want. We want a nice smooth transition from the bowl to the runner. Use your finger to feel how smooth it is. Just take out any hard edges or sharp transitions.

I documented my porting adventures; you can read it over by following the link at the end of my sig.

 

I have read your thread a few times, sitting bull. Anyone with half a sense and intrest in porting should have by now!

My concern was that i shaped the short side radius too much. Its very smooth, but i removed some metal there and flattened it out some.


Sonix you will know how its running soon bro! I dont know if you remeber talking about the budget 350 im building, but i finnaly decided on the XE268 because JEGS has it for 70$USD now! almost a steal IMO. If you buy the lifters seperately you can get the cam/lifters for 140$..

 

today i got a lot done, one head is completely "rough cut", minus the combustion chambers. The other is about half rough-cut.



i ran into a problem though... i struck water in one of the intake bowls. Its the only one cut even remotely this deep, its from when i first got the double-cut cutter and had troubles with it digging in. well last night, while shaping the valve guide boss the grinder "jumped" off smasing into the wall, making a hole. it was pretty thin here apearently.. Is there anything, like an epoxy, that i can use to fix this???

I've seen some high-temp epoxy's good for 1200F, would one of them work?

Can i use epoxy to fill in the gapping hole under the rocker studs inside the intake runners??


Thanks for any help here, i need to get this done so i can get my car back on the road.

 

yes, epoxy works on the intake side.

Good job so far, dont let this discourage you

 

You're getting way to carried away on that side of the guide boss.

 

Look at the blue arrows in the pic. You do not want to hog out the one ide of the bowl to match the other side.
By doing this you are destroying the port bias. Port bias is good. gives you swirl.

Do not try to make the wall vertical on that side of the bowl( (purple arrow)

 

you got way too carried away opening up this side of the bowl. (red square) The wall appears vertical now. it should be a funnel. Post another pic of that bowl from staight down the bowl from above.
i think ya F**** up.

 

that side being so cut down was a total accident. It was the first time using that good cutter and it kept digging ruts from my lack of control.

So a high temp epoxy would be ok to repair this and not leak?

Do you know if i can fill in those gapping holes under the rocker studs in the intake runners?

Sorry everyone whos intrested, i took many pics, but none turned out good. I'll get some more with better lighting soon.

thanks again for the help!

 

Yes you can use the expoxy to fill the gap in the port roof.
Got ton get the carbon off the metal first thou. Sand blasting and then brake cleaner is good.

 

Thanks Fbird88 you are a great help here


I'll get you some pics from different angles tomorrow. I hope it isnt too bad..

 

You might try brazing the hole up.

 

since you've ground it, you shouldn't have to sand blast (unless you mean from the other side?) but yes, degrease for sure.

there are epoxy putties, that cure under heat, and can withstand the 1200F stuff.... (according to their ads), but like these guys are mentioning, the intake side doesn't get very hot, so it's not a huge worry...

I'd like to hear more info about this "straight wall = bad" thing...


FWIW - looks like the guide boss itself is well done.

 

heres some photos for you all;

 

That looks good so far

I hope you arent done (or the lighting is just being wacky and making me see things) cuz it looks like you still have more straightening to do.


Keep up the good work, it's showing off !

 

thanks sellmanb, your right, they arent done yet. lots of clean-up needed still..

where are you talking about that needs straightening though? The place im thinking of is where the head bolt goes between what i thinks called the common wall near the bowl. Its tough to get too though, not having a 6" shank carbide. I can just get to it with cartrigde rolls that came in the SA porting kit, but the grinder hits the intake entry too.

the other pic i forgot to upload ;

 

on your first (new) pic, does anyone think you can bring the valve guides lower then that?

I like that last pic, very good looking IMHO.

one dubious question I have (as so far i've only played with my 993 practice heads...), is what is that?

EDIT:
oh yea, and remember, a lot of flow is gained from porting very close to the valve seats (of course, where you can do the most damage, go figure...), just avoid the actual seat itself, but I think you can remove that ride 3/16" below the valve seat.... anyone concur?

 

im no expert sonix, but those viods you labeled are "under" rocker studs as far as i can tell.

i've read that filling them in is good for a lot of flow.

I think the valve guides are short enough. As long as they are streamlined and thin they are good. thier hieght doesnt mean much once the valves are installed, from what i've seen.

when i went to JEG's to pick up my cam and valvetrain stuff i stood there looking over an AFR head for a long time. thier valve guides are probably even taller then mine are. also they have a really nice radiused transition from the runner to bowl, a long gental slope nearly all the way to the valve seat.

 

there's still a little more straightening you can do there on the runners. Dont go hog crazy, but it looks like you're at about 70%, where you can safely go about 80-85% straight on those.

 

these are 416's done using vader's templates and alot of other members advice, you can go quite a bit further on the common wall.

 

here is another pic of what I did with the intake guides and the deshrouding. it doesn't show the port bias very well though, it looks alot smaller than it really is.

 

the six inch bit with the yellow tag on it is the money maker
f-bird88 is talking about

 

That would be the one.

 

hey f-bird, would you believe those are the same heads I started with almost a year ago.

 

becuase the port roof has been scooped out and made deeper ( Blue arrow) the whole roof ( green x's) needs to be raised to straighten it all the way from the bowl to the inlet.
The point at the red arrow needs to be straightened as much as possible.