FE Intake Adapter

[bartlett]

Look's great JAY !  Remember jay I got a Test Fe just down the street from you ! 

[WConley]

Nice job Jay.  I could have used one of those lollipop mills for a four cylinder intake adapter job I did.  I ran into similar undercuts, which had to be hand massaged after machining.

I'd love to hear more about how those tools work out.

- Bill

[machoneman]

Neat how having the right tool speeds the process.

Do you intend to run the first one on an engine right away?

[jayb]

Neat how having the right tool speeds the process.

Do you intend to run the first one on an engine right away?

Yes, I have my 428CJ on the dyno, waiting for the first adapter.  After I get done with the first one on the dyno, the engine is coming off and going into my '68 Mustang "rolling test bed", for road testing the intake adapter, the clear valve covers, and the CVR water pump adapters. 

[machoneman]

Cool! 

[jayb]

Nice job Jay.  I could have used one of those lollipop mills for a four cylinder intake adapter job I did.  I ran into similar undercuts, which had to be hand massaged after machining.

I'd love to hear more about how those tools work out.

- Bill

So far they have worked out really well.  I bought a couple of much bigger ones several years ago, when I was doing the CNC porting work for the adapter plates I built for the high riser engine.  Those had a ball diameter of 1.0", and a shank diameter of .375".  What this meant was that I could effective cut a radius down to 0.5" and make an undercut of 0.3125".  Since the corners of the ports in my high riser heads were 0.6" radius I was able to cut the whole port with them, and get a .300" slant to the port from top to bottom.

The small one shown in the photo of this thread is a .375" head with a .1875" shank.  So I can cut down to a .1875" corner radius, which just happens to be the corner radius of the Edelbrock head ports (as mine measure, anyway).  The downside is that I can only undercut up to .093" with this tool, and I have a 0.200" undercut that I have to make.  When I bought that cutter I was a little concerned about how rigid it would be with only a .1875" shank, but the cuts I needed to make over the weekend showed that it was plenty rigid for my application.  I'll be ordering a couple more cutters this week, with larger balls, to make the required undercuts all the way to .200".  From the FE port to the 351C port the corner radius increases, from .1875" to .425" or more, so as the undercut gets larger, so does the radius, and the ball end of the cutter can get larger in diameter.  I will need 3 different cutters to make the whole port, but at least it is possible without a 5 axis machine.

A bigger concern is that I'm up to 19 tools required for the operation with the manifold on the trunnion table.  I only have a 20 tool toolchanger!  Thankfully, I don't think I need any more...

[jayb]

Look's great JAY !  Remember jay I got a Test Fe just down the street from you ! 

Hmmm...  Is your engine dyno-ready??

[gbagitator]

Ha Jay  I have a new Wei/ 351 c  tunnel ram with a common plenum & efi inj bunts welded in  Your welcome to try it on your adpt.  I Quit racing before i got to finish it   Gord

[jayb]

Thanks Gord, I'll keep that in mind...

[cjshaker]

Just wondering, did you narrow the port at the transition, or did  you move the pushrod bore over where it broke through?  It would be a shame to lose cross section there, but as long as it can mate up to the widest FE cylinder intake port, I guess it wouldn't matter.

edit: Looking at the pictures closer, the pushrod hole seems fairly big, so hopefully you could just push it over a bit to still leave some blending area to mate with the head port.

You know, with offset rockers and lifters, coupled with a nicely set up runner system.....
Have you wondered about potential flow # increases? Or are you strictly looking at this from a "plenty of intakes to choose from" standpoint?

[jayb]

The issue with the pushrod hole was just a machining error.  From the head, I wanted the port to come straight out about 3/4" before it started bending around to mate up with the 351C port.  But on the first port I forgot about this, and just programmed a straight line from the inboard side of the FE port to the inboard side of the 351C port.  So the straight line intersected with the pushrod hole and broke through.  On the rest of the ports I didn't make that mistake, and the ports are the full width of the Edelbrock MR head port, less about .050" on each side left for port matching.

Since all the parameters of the intake can be adjusted via the CNC program, I could easily spread the pushrod holes apart to allow for a wider than stock port and offset rockers.  Or, I could make the holes smaller to allow for a wider port.  Or, I could deliver a custom manifold without any pushrod holes at all, and let the end user put them in where he needs them.  All kinds of possibilities here...

[Joe-jdc]

What I would like to try/see would be a smaller pushrod hole that is elongated for pushrod travel, but just wide enough for heat growth.  That would leave lots of room for angling the port for different intakes.  Joe-JDC

[fe66comet]

If I am using the Edelbrock RPM gasket and a 4v intake would that be a good match with a stage x  head ? Thanks Jay......Jon

[jayb]

Yes, that should match right up - Jay

[jayb]

Just a quick update on this project.  Earlier this week I discovered, much to my chagrin, that ports 5-8 could not simply be mirror images of ports 1-4; the problem is that if you do it that way, the port 8 hole gets too close to one of the FE intake bolts, and overlaps the counterbore required for the allen bolt that is fourth back on the driver's side.  So, basically the center of the 351C intake has to be shifted back just a little bit compared to the center of the FE intake adapter.  This changes all the port configurations, on both sides of the intake.

So I spent the evenings and most of this weekend writing the code for the ports 5-8.  I machined them today, and of course there's a few little tweaks that need to be made, and also ports 1-4 need to be modified so that the 351C manifold moves back.  But the basics are done now; I just need to make some modifications to the programs and hopefully I'll be good to go.  With the four day July 4 weekend coming up, I'm hoping to get the modifications made and the first "for-real" intake machined.  I also need to get the center opening cover plate machined; working on that now. 

Of course this is taking longer than I wanted, but maybe next weekend...