Bernhard

If you are looking for flow numbers on a well ported small block head Rally Bob posted them on ROP.
I look forward to track numbers from these heads

67 Cutlass Freak

I think welding in the dividers we got from Lars will be easier and have a good finish. I would be worried about the aluminum breaking away without being pinned in as described by Mister Kwik. How do you like the valve job posts I made?

coppercutlass

I got a system that might work to hold the alloy down. I didn't read how quick 442 did em but if you made serrations along the stock divider then drilled holes into the bottom of the serrations the entire pour would have something to hold onto . Kinda like what they do in wood work for good furniture to hold the ends together. I made a quick template and it actually looks pretty damn air tight. if we where to do this I think some of that high heat shield putty will work so stuff don't ooze out. I'll post pics of what I made. I was bored and went down to the basement lol.


Dave the valve job looks great and you are going above and beyond what I ever expected you to do. I would have been happy with just a simple valve job lol. Im gald you are doing what you are because it has changed the direction of the build. With work being slow im gonna hold off on buying stuff. I got the money to send the rotating assembly and the block out but I don't wanna spend any money until work picks up or after tax return .

67 Cutlass Freak

Yeah 247 & 149 @ .500" lift looked pretty respectable. It also explains why he chose to run the Rocket Racing heads.

coppercutlass

he still ran 10's with the irons ! Which blew my mind the first time I went to the track with my buddy years ago.

coppercutlass

Here is what I came up with. The real deal will have to be a two piece deal so we can use one for the center and one to over the port. Having a 2 piece set up will also allow the use of some form of putty to avoid slag to come through the slight cracks. I know welding and filling the whole thing with welding take a lot of work this might be easier and quicker to clean up. I also figured the allow wont stick to well to a slick surface like smooth sheet metal and maybe a wax coating before use will help it not stick. Just a thought.

firefrost gold

coppper won't the contour of your head be different now that he has cut it ? Race logic
had a template that you put on two stroke jugs to get a idea of how far to cut and open up transfer ports I know Mondello and others have talked about porting is there a rule you use or one other porter said he just got a mind set of being a little air molecule going down the intake track and out the exhaust after combustion .

coppercutlass

Well I wanted to see how well I could get it to seal. There maybe a slight difrence but I think we can use something like common mudd for example to cover the little crevices while you pour in the alloy. Sheet metal is cheap enough and you can always leave alittle material. And grind to fit. One of the body guys I used to work with used to use mud like dirt and water and he would used it as a heat sink to lead seams on cars when we replaced 1/4 panels. He would mix it to a thick mixture kinda like dough and put it adjacent to the welding aread so the heat would not travel far and warp the metal. I think this would work to fill the crevises as getting a perfect seal would be very hard to do with just the sheet metal. If not I think there is a heat resistant putty for welding .

Bernhard

There was a clay that we used in the body shop to stop heat transfer when there was a lot of welding required. The use of the clay and proper stitching kept the repair from warping.
If you go with a pour I would make sure the surface was sand blasted clean. The one that was posted with the aluminum divider looks sweet, the only concern I would have is dose it stay in place?

Lars

this is a slick design, ends up being one piece not 2 sides, the one piece would be held in by the pins and header also. looks good!



And copper, just use dirt or sand to full the port after you set the template, I would grind down the center devider to make the poor stronger, the wings will have more support.


if you in reader land don't have torches or a stick welder you can make a clip out of 3/8 flat stock, it'll just take a week to grind and fit in

coppercutlass

I like the sand idea but the valve job is done. Idk if that would be the best idea but I guess a simple clean up will also do the job. I'm gonna start transfering my cardboard template on to sheet metal. Also I feel if you grind its the same thing as the cast texture because both offer mechanical adhesion. If anything maybe some x style serations along the sides of the diveder along with the dove tail style joint at the very tip of it would hold. I think the header will hold in the poured in aluminum divider and it it broke it would blow into the exhaust. I'm not too worried about it if I we chose to go this route.

Smitty275

Well, I admit I've not read this entire thread, though I have skimmed through it. I've got a few things I'd like to share for the home porter.
Having a set of dividers is an absolute necessity. You can use them like the snap gauges only they are easier to hold to a scale (ruler) and you just drag them through the opening. Try to make each port the same width and height in the same areas.
Cut the intake mouth as straight in as you can. Avoid the pushrod on the hook side though. IF you hit the pushrod hole all is not lost. You can use a high quality epoxy or sleeve it with brass tubing sold in hobby stores. On the area behind the pushrod hook blend it into the mouth of the port as best you can. Also straighten out the walls of the port to remove the core taper. The walls should be straight up and down, not concave, and have a nice small radius blending into the roof and floor. On the roof remove the "bulge" and smooth it into the rest of the roof. You can safely straighten then out until you have removed the "parting line" where the cores came together. DO NOTHING to the floor of the port on the intake side. Absolutely NOTHING.
When you get to the intake bowl you want to cut the bowl area so it is round behind/beside the valve guide and nearly all the way out to the seat. Very little bottom angle under the seat angle is needed if any. But it takes patience to get it close. Better to leave a little than get into the seat. As far as the valve guide goes it is honestly a PIA to work around and shows absolutely no gain by tear dropping it unless your into that extensive stage of porting in which case your going to be using a bench to verify the results. With all the work people put into the guide area thinking it makes a big difference you'd really be disappointed if you could flow the port before and after just working the guide. Make the short turn as short and low as you are comfortable in taking material away while keeping it blended into the port floor towards the intake.




On the exhaust side it's all in the bowl, the guide, and blending them into the port exit. Cut straight down from the seat and make the guide as small as you can while blending it into the roof. Going from the bowl into the port you should be able to feel a ridge on the walls with your finger. The better you get rid of this ridge and blend the bowl into the port the better off you'll be. As with the intake ports straighten up the walls of the port so they are straight up and down, not concave. You can safely straighten them until the "parting line" disappears just as on the intakes. Next put an exhaust gasket in place and scribe the openings. Get a small machinist square and cut the port walls straight in from those lines. Blend them into the roof and floor with a small radius of about 1/4". You'll have to re-blend the area that comes from the bowl at this point. Now for everyone's favorite exhaust port modification. The A.I.R. "BUMP", Protrusion, or what ever you like to call it. Make it as purdy as you want. Just don't get carried away with it. Removing the bumb is worth an entire 2 CFM. Yes, ladies and germs, you read that right, an entire TWO CFM. Almost hard to believe isn't it for all the fuss that has been made over the years about grinding it out. As I said in the beginning it's all in the bowl, the guide and how well you blend them into the rest of the port.


Always pour the crossover if you can. You don't need to get it all fussy and super elegant. It has minimal effect on flow, but it has MAJOR effect on making the motor function with 8 separate exhaust pulses so each cylinder has the same scavenge effect. It also gets rid of excessive heat from the center of the head since the exhaust is funneled out of the head instead of just popping back and forth between those two cylinders.


On the exhaust divider. I've been pouring them for years something similar to what was shown on the previous page or two. Drill two 1/4" holes through the iron for the aluminum to grab onto, put up shields to shape it from the bolt hole to the end and pour it. I've yet to have one come out or melt away. I have had one that was wiggly after a few years of being run hard though. The header will keep it in place even if you don't drill the holes through the iron.


As for what to pour with..................ZA-12. I know we've all used old pistons and melted them down to pour with and ya it works more or less. But the ZA-12 melts easier, because it is cleaner, and pours much easier, because it is cleaner, filling voids and such that the pistons won't. A chunk of ZA-12 is a whopping $25 bucks and will do 2 pairs of heads if you don't waste it.


For valves: Always put the biggest intake in that you can and keep the exhaust side to 1.625 unless seat damage forces you to go larger. That goes for big or small block. Seats narrower than .060 don't help a thing, flow or otherwise, be it intake or exhaust.


And as with anything there are always exceptions to the rule. I.E. Some heads had 1.680 exhaust valves from the factory. But they were a 30* seat and usually it's no problem to change that to a 45*. So on and so forth. And no matter what the exception might be, do not over think it. This stuff really is simple and easy to work around what ever you might come up against can be solved.



So that is the best "simple" advice I can give to those of you who home port. This info will not get you anywhere near a full race head but it will make for a very productive head be it a SBO or a BBO. If someone lives close enough and would like to come over for a Saturday or Sunday and port a port or two, cut valve job, etc. with my guidance and take pics of it to post here just let me know. There is only one catch. You have to FEED me......... all day. We have decent places for breakfast, excellent pizza shops, and only 12 minutes from Texas Road House.

67 Cutlass Freak

Wow that is a really cool offer. I wish I lived closer. I would definitely take you up on that. I'd even buy the beer. Thanks for your very informative post Smitty. This is exactly what I was hoping for, and just what this thread needed. The only thing that would be better is if someone got there butt to your shop and snapped off some photos. Now I think you better get over to the debate thread and tell everyone what you think about the performance capability of our beloved cast iron heads.

captjim

It isn't about the capability, it is about cost-effectiveness. I don't think anyone will argue that you can't make these engines run good with iron heads.

Great post, Smitty. You confirm several things I have said numerous times, big intake valve, focus on the bowl, and removing the "bumps" does very little.

Bernhard

Smitty What are your thoughts on removing the valve guild boss altogether and using sold bronze wall guilds for support.
This mod for a race only car or also for a street strip car?

Smitty275

Its a 50/50 proposition. I like to maintain the integrity of the casting as much as possible. Therefore I use guide liners the majority of the time. I tend to only use solid bronze guides when I have to. Like when the top of a guide has been completely broken off.

67 Cutlass Freak

Well guys I've finished the valve job on Copper's heads and I think they turned out real nice. The exhaust valve is pretty much just like the intake except the seat contact area is wider and I like to locate it right in the middle of the valve. I went .060" on these-
CIMG4352.jpg
CIMG4344.jpg
We have decided to do a poor on these for raising the divider. I will try to get some decent photos. The next thing I wanted to discuss was measuring installed spring height and adjusting valve stem height. These things are really crucial if you're going to run the stock valve train. I think I will try to document this on this next set I'm porting. I've already got three of the intake ports and bowls done. This next set I'm doing are for J (Chicago). He really wanted to run the stock rockers. This does pose a challenge. With stock type valves from a BB the stem height is too low after enlarging the seat. Aftermarket valves are typically .010" taller to allow for adjustment. I picked up a new set from ProComp for dirt cheap. They were advertised as 2.07" with .341" stems. They are the perfect length, but they measured 2.068" and .339" stem. They fit way too sloppy in the guide. Jeromy contacted Milan, who has informed us this is very common for aftermarket Oldsmobile valves. This pretty much forces you to do guides or spend big money with Mondello's. That's where I got the valves for Copper's heads, and they fit perfect. The guys at ProComp told me these valves were designed for their heads or their bronze guides.

oldcutlass

So now that his heads are basically done, do we have cost estimate to run with and an approx. amount of time spent. This way people can make a judgment call for budgeting.

67 Cutlass Freak

Well puting a price on the port work and valve job might be a little tough, but I'll do the best I can. First I want to say that I did this as a big favor to Copper Cutlass, because I was impressed with his budget performance build. I was going to show him some porting techniques and help him do his first valve job. After the first time we met, I decided to basically do the work for him, because I didn't think he had all the necessary porting equipment, or knowledge to do it. I really wanted to help him reach his performance goals and stay within budget. We have a gentleman's agreement, that he's going to help me with the paint and body work on my race car. He's already done a bit of work on the roof. To date no money has exchanged hands.
The biggest expense I have in these heads were the stainless steel valves from Mondello's. They were $300 for the 1.99" intake and 1.64" exhaust valves. They are real nice but over priced in my opinion. The Pro Comp valves that I just picked up were $54 per set. The performance spring retainer kit he already had, but I think they sell for $75. The Viton seals he got were $30 from Summit. The special intake gasket was $24.
Obviously I wasn't punching a clock while working on these heads, but I think that I have close to sixty hours into them, including the porting, and valve job. If I charged $10 per hour, than we could say the value on these heads would be close to $1000. My friend is going to resurface them for $40. It's hard to put a dollar figure on what it cost to heat my garage or the electricity usage for my compressor. The cost of keeping my garage refrigerator stocked is mind boggling. The other costs that are tough to calculate are the porting supplies. I've been collecting bits and abrasives for years.
To do a fair comparison, if someone had good used valve train components, and all the equipment to do home porting, or a basic three angle valve job, than the cost would have been less than $100 for gaskets and seals. We were going to go that route, but I had the new valves here, and wanted to do the best job possible. The way I see it is, after all that work with porting, to throw in some used valves, would be like frosting a cake with poop.

coppercutlass

BTW thanks dave. You went above and beyond what I wanted to do with these heads. I really appreciate all the help and time you have put into the heads. Hopefully once the weather gets nicer we can put in a few long weekends on the 67 which im looking forward to being able to help you out .

captjim

I think what oldcutlass was getting to is what would a regular machine shop charge to duplicate the work you did on these heads for free. Then, a fair comparison can be made. Also, $10/hour is not a realistic labor charge for porting. If you double it, which is still about half the going rate, you are at $2,000.

67 Cutlass Freak

Jim I've never paid a machine shop for porting service, so I really can't say first hand what they would charge. Back on page one, I posted a price sheet from Mondello's, listing different porting services. Maybe Smitty or CJ would like to comment on what they charge? You say $10/ hour is not a realistic labor rate, well for a guy working at home, in his spare time, I would be happy to get that for porting service.

captjim

That is fair, but I also think it is fair to post what the average guy who has to pay a shop to do it would pay. Maybe Smitty or Mark will chinme in, but I'm thinking based on my experiences that it is closer to $40 an hour. Granted, a professional porter will probably have less than 60 hours in them.

If you are willing to provide that service for that price, you shoukld have more work than you can handle.

cutlassefi

Around here the going rate is about $60.00/hr.

oldcutlass

So in parts, $425.00 + labor in hours for performance valve job + labor in hours for porting. Because you did both functions.

coppercutlass

I think fwiw most guys who will build a street strip set up appx 400 hp can get away with less work. Thus costing a lot less. But an all out set of competition heads will run a lot more. My heads done by rrp can support appx 400 hp and the whole top end ran me 1600 bucks and that's with paying the upcharge on parts all they did was bowl work and big valves . A set like what dave did will clearly run more but let's face it most guys running sbo's bearly scratch the 400 hp surface that's not to say they are duds but that's how I see it. I'm yet to run et's that refelect 400 hp and my previous set up could have possibly scratched 12's. That's my take on it.

coppercutlass

I might add daves thread is not about budget its about porting at home atleast that's how I see it. The budget end is on my build which I'm going to adress the prices but what we/I did to spend less on my thread. The reaity is for an iron headed small block you don't need a whole ton of port work to get 400 hp.

oldcutlass

I agree with you copper, I was just curious on about what it took to do it. After all is said and done, we also have to see if it is really worth going this route in the long run. At least that's my take on what the opposing argument is. The questions are is it better performance wise? Can you realistically do it at home and have get everything matched correctly, even if you farm out the valve job and the machine work associated with it, because most of us don't have that equipment in our garage. And are the gains achieved worthwhile compared to say an out of the box pair of aluminums. And a comparison of cost differences between the 2 approaches. I think that covers all the questions. Please correct me if I'm wrong.

captjim

Not sure I agree with that.

captjim

I think your questions are rhetorical (meaning you already know the answers) Ported iron ends up where the aluminum starts. Plus all of the other advantages.

captjim

So, $325 for a good valve job plus $125 for guides and you are at $925 before porting? and the Pro-Comps are $1100? And the dividers are welded? And the crossover is filled? And they are lighter? And .....

I will agree that for a stockish SBO with decent valves that can be re-used, rebuilding the iron with a little bowl work and a good valve job might be a better approch with lesss hassles. But, realize that you ARE leaving performance on the table. IMHO.

holiday88

Question about blocking the crossover passage. Would I get the same effect by blocking the passage with a shim and gasket covering the passage? It seems that flow increases on the center ports when the passage is filled with aluminum. Or is the only benefit in preventing the heat from rising into the intake?

coppercutlass

I'm going to post up the whole detailed parts and cost list for the heads rrp did for me. This way we can all see what that ran. I think those heads can hold up to 400 hp. With no issues really imo. RRP told me to do a street strip port job that would run 600 .

455man

Filling it with aluminum is best because it separates the exhaust ports and increases flow. Blocking it off from going into the intake separates it from the other two exhaust ports on the other side and does not put as much heat to the intake. So there is some benefit to just blocking off the crossover but not as much.

captjim

I agrre, it also helps with scavenging as the chambers are separate. Also, whatever you use to block the crossover will probably burn through in a short time.

holiday88

thanks 455.

Freak, where did you get the procomp valves from? Were they stainless as well? The price is good. I'd like to have a look. thanks.

coppercutlass

I hope you guys can see it I don't have a scanner but here is my receipt from rrp. That's 1445-50 for the main bearings. that's 1395 I also did not pay tax.

captjim

The link did not open for me and I have no idea what this post is about.

coppercutlass

I'll fix it sorry for that. Its suppoused to be what my total was for the #6 heads rrp did for me. The link worked for me.




Edit : fixed it jim now you get it .

captjim

Gotcha, I see it now, thanks.