Manifold flanges

I converted this into the following DXF file. Save the file, change the suffix from txt to dxf and you should be good to go. The file did change a smidge, the overall part length went from 394.43mm to 394.46mm which should be an acceptable level of variation over the parts at least to start. I can spend a bit more time and improve that if needed.
 

Attachments

  • 20130004_Uno_14_Turbo_InletOutlet.txt
    1.8 MB · Views: 76
I had problems with burn through on my gaskets and after the second attempt to solve I decided to do the feel/meely on the flange. The ceramic coating was applied to the flange and my dad installed without removing the material. Much it cracked off and until I filed the flange clean I was never getting a seal!
Not sure what I have for manifolds... When I get back to my stuff(Wednesday) I can let you know.
If you are going to use a stock downpipe and beyond you will need the Fiat manifold gasket for a pattern. If not you can just buy a two holer from mandrel bends... Two actually, one from header and one to exhaust.
Either way I will check back in Wednesday and let you know what I have.
Regards

How about a graphite gasket that is good for 3000° F and crushes from 1/8" to 1/16" which pretty much will seal any reasonable surface defect or mild flange warpage?
http://catalog.remflex.com/FIAT_MANIFOLD_HEADER_GASKET_p/37-001.htm
 
perhaps contact this chap
Simon, amazing! Thank you for bringing this to our attention, absolutely perfect.

I converted this into the following DXF file
Karl, nice job. Thank you for doing this. I'll forward it to my contact and see what's next. I also need to check the diameter of the ports for comparison with standard U.S. tube OD's (being from Europe I'm not sure what materials they built it for).

a graphite gaske
Dan, nice find. I've never heard of this place. According to their site they have been around for a long time but new to the automotive market. Sounds like great material. By chance anyone have experience using it? I will contact them to discuss other product ideas. Hopefully they come to SEMA this year so I can get a first hand look. Thanks.

[Karl, I know, I'm cat herding again...can't help myself when so many exceptional people pitch in. Thanks everyone.]
 
I can go in and adjust anything that needs it to better meet the materials used
 
I used the dxf Karl provided and am in the process of cutting a flange, My plasma table is grumpy this morning so it may take a couple try's to get it set up. hopefully I'll have one today so you can see how they look.
 
Let us know how it goes. I will be out touch quite a bit over the next two weeks so I won't be able to make adjustments until after the weekend. Hope it turned out well.

I might be able to do some government work at work and have one lasered out when I get back from vacation around the 21st.

Karl
 
Last edited:
The DXF is fine, I cut 2 flanges but the cut quality is crap, the grumpy plasma... Something in the post processor has taken a dive and the touchoff isn't working right which destroys the tip on the cutter and it cuts like crap. Back to programming 101... I'll get it straightened out and get a cut to test fitment soon. Grumpy machine makes for a grumpy operator, maybe I should start drinking....
 
Brian, sucks the machine is acting up on you. Speaking for myself, there is no rush on this whole thing. If you get it working right then a test piece can be cut for a comparison fit on a head. Then if everything is good we can decide how to proceed. However if you prefer I can see if the overseas contact will cut a test piece from what we have so far. Thanks for your involvement.
 
Finally got the machine to submit. Here is the first cut.
20170803_080502.jpg

and on the engine.
20170803_084255.jpg


The pattern is close but needs some tweeking, you can see the bright silver through the flange on all 4 holes, that's how far off the holes are. I have no idea how far off stock manifolds are or aftermarket headers for that matter.

I cant seem to edit the DXF file or measure anything on it so I'm thinking about pulling the head on this engine, I can fixture it up on the mill and use the DRO to locate all the holes, then I can model the port side of the head with all the correct placements then I can move the holes as needed.

Anyone in the Portland OR area have a head off that could be used for this so I don't have to break down this engine?
 
Brian, I have the head from my '86 off in SE Portland; I got a performance head from MWB, old head is just sitting around.
+1 on the Remflex gasket, working quite well, I got one when I redid my motor from a recommendation from Dan made before; I want to get a header flange gasket made of this stuff too.

Jeff
 
Last edited:
Hey Jeff, You going to be anywhere near Vancouver anytime soon? You know I have an allergy to Portland... I would only need the head for a day or so.
 
I just put the flange up against the exhaust manifold and it was farther off than the head. it appears that the manifold has a bigger port than the head to compensate for manufacturing tolerances so the .050" the flange is off may be within tolerance for a stock head casting.
 
Brian, nice that you got your machine working. If possible it would be great if we could tweak the file to fit better. That way the data file could be used as needed by anyone in the future.

Do you happen to have a manifold gasket to compare with the head, the manifold, and the flange? I'm thinking if the gasket proves to be a great pattern (accurate fit to the head dimensions) then maybe it can be used as a measurement template by someone that can tweak the data file. Unfortunately I am no help with this type of file.

By the way, I've often found on many different engines that exhaust manifolds have slightly larger ports than the heads they fit. Guess it is as you say to help with tolerances because the ports on the two usually don't line up that well. And manifold gaskets are typically even worse for the same reason. Therefore it would be best to measure off the head rather than the manifold or gasket, but see what you find out.

Thanks for keeping this going.
 
I'm working on getting a Head from Jefco this weekend so I don't have to break down my engine. If this works out we will have a file based on the center points of the openings so we can adjust however we need and cut the holes any size we want for the different tube sizes people may want to go with.
 
Just like to say that exhaust flange port holes are best to be slightly larger than the port size to help prevent back flow into the head.
 
Finally got the machine to submit. Here is the first cut.
View attachment 3967
and on the engine.
View attachment 3968

The pattern is close but needs some tweeking, you can see the bright silver through the flange on all 4 holes, that's how far off the holes are. I have no idea how far off stock manifolds are or aftermarket headers for that matter.

I cant seem to edit the DXF file or measure anything on it so I'm thinking about pulling the head on this engine, I can fixture it up on the mill and use the DRO to locate all the holes, then I can model the port side of the head with all the correct placements then I can move the holes as needed.

Anyone in the Portland OR area have a head off that could be used for this so I don't have to break down this engine?

So the first question I have is are the bolt holes correct? The one hole that I can see on the left side looks concentric with the opening of the stud. Are all the rest of them good as well?

If the bolt holes are good, then we can tweak the placement and diameter of the openings with ease. Using a micrometer or digital caliper to call out the changes from what it is now would be all I need.

Karl
 
Just like to say that exhaust flange port holes are best to be slightly larger than the port size to help prevent back flow into the head.

That's mostly correct... but in an IDEAL situation you would want the top of the port to be totally flush with any pipework, and a step at the bottom of the port... the differential being the high flow (fast side) of the port is the top, and the slow side (at the lower half) is where you want any anti-reversion step.

So rather than plotting the precise centre of the port for your cuts, perhaps move the centre down just a touch... and yes allow for the OD of whatever pipe size chosen, as really you want to slip the pipe into the flange plate.

SteveC
 
Karl, the bolt holes are a bit off as well, I had to drill them oversize to get them to fit and I still didn't get all of them, as you saw 1 didn't have a bolt is was still off by a touch. but then again the holes in the stock manifold are 10mm and these are at 8.5 on the full holes, I didn't mess with the half holes.

The main holes are all off in different directions and different amounts 2 need to go in the 4:00 direction and 2 in the 8:00 direction, also very difficult to measure as the hole in the flange is a little larger than the port. I think it will be easier to just fixture the head and get the center locations for each hole and references for the outline then hopefully we can merge the holes into the existing drawing so we don't have to recreate the outline.

In your drawing are the holes a single circle? in the one I downloaded they are all tiny segments that I can't do anything with, just wondering if it was something in my import or if that's all there is.

I will be picking up Jeff's head this afternoon so hopefully over the weekend I'll get it measured. Once we have the center point we can align the top of the tube with the top of the port as Steve suggested.


So the first question I have is are the bolt holes correct? The one hole that I can see on the left side looks concentric with the opening of the stud. Are all the rest of them good as well?

If the bolt holes are good, then we can tweak the placement and diameter of the openings with ease. Using a micrometer or digital caliper to call out the changes from what it is now would be all I need.

Karl
 
Hi Steve, any idea how close the head castings are to each other? or do they wander around a bit through different production runs? Just a curiosity.

That's mostly correct... but in an IDEAL situation you would want the top of the port to be totally flush with any pipework, and a step at the bottom of the port... the differential being the high flow (fast side) of the port is the top, and the slow side (at the lower half) is where you want any anti-reversion step.

So rather than plotting the precise centre of the port for your cuts, perhaps move the centre down just a touch... and yes allow for the OD of whatever pipe size chosen, as really you want to slip the pipe into the flange plate.

SteveC
 
Steve's info on the port flow characters is awesome, the type of data that can only be found through first hand experience and testing. Definitely worth incorporating into the design.
 
Back
Top