Early 505 square port intake manifold questions

Pug72

Pug72

Active member
Fellow Frogger
Joined
Feb 11, 2013
Messages
537
Location
Brisbane
Hi all

Can I please get advise as to what inlet/outlet goes where on the early 505 intake manifold?

I am fitting an early 505 square port head to my 1972 504. The current manifold has a large coolant inlet, take off for the vacuum to the brake booster and a breather linked to the crankcase ventilation.

The later intake manifold has a few extra hose barbs and threaded holes. As per the pictures attached, there are 4 hose attachments and 2 threaded holes.

inlet side.jpginlet.jpg

Obviously some of these will be blanked off to make it work on the earlier engine, so I just want to make sure what's the best way to go and which to blank off.

Thank you
 
Here is how it is set up on my 1985 505 SR which has had pollution control removed :

First photo :

Top hole is coolant (obviously). The second one is blanked off and the bottom one has a pollution control thingy screwed in but unconnected, so blank it off (as far as I remember, they are not metric thread so go to a hardware or plumbing place and get a couple of plugs....it's plumbing size thread ! At least, the exhaust side of things is definitely plumbing type thread so I'm guessing these are also..

Second photo :

Top hole goes to brake booster and other two blanked off. Though one may be used for crankcase breather, depending on your current setup.

BTW, if you are not already aware, the crankcase on these doesn't just breathe....it operates on negative crankcase pressure. In other words, fumes get actively sucked out.
 
Last edited:
The big spigot on manifold goes to the upper, smaller spigot on drivers side of the water pump. You will need to adapt the hose sizes.

I used copper solder type plumbing reducers soldered into the right size cooper pipe.

For the sake of being complete, the spigot on the rear of the head on passenger side goes to the heater.

If there is smaller branch it can be blocked off.

The other heater hose, which will need to adapted to 25?mm goes to the big spigot on the drivers side front of the water pump.

I believe your manifold may be missing a blanking pressure plug, directly above the pp in the image.

The vertical spigots, with hex tops are for vacuum for power booster and A/C idle up if fitted. Block the ones you don't need.

Distributor advance should be connected to a port on the carby base.

manifold.JPG

This from memory so E&O should be excused.
 
Thanks guys, I will make a trip to enzed for fittings as I have had luck there before with hose barbs/blanks
 
The rear of the head rear can be tapped with 3/8 gas thread tap and 16mm brass barbs are available to fit.
 
The square port head/manifold on my '79 504 has the three large openings on the LH side. The top one is coolant. the middle one is blanked off with what I took to be approx 18mm thread in hex plug. Interesting that others have found the thread to be BSP [gas?]
The lower one is a common "Xmas tree" vacuum fitting, mine has been happily left in place.
The two smaller take-offs are rear, for the brake booster. The other, similar but with a restriction is for the engine breather/
oil filler.
The other forward facing small attachment on mine has been blanked off. I've used this point for my "FlashLube" injector.

All the above is similar to previous posts.
My 504 has been converted to the obligatory [Cortina] Weber. Everything is simplified by the removal of the Solex choke hoses and the EGR valve and plumbing.

The only other mods done have been to an overflow cooling system bottle [Unipart] and a HotSpark pointless ign system.


Pointless ign system meaning sanspoints!
 
what I took to be approx 18mm thread in hex plug. Interesting that others have found the thread to be BSP [gas?]
Click to expand...

The only gas threads I've found in Peugeot components is after I have tapped them myself.

Mainly corroded spigots in the lhs rear cylinder head. Once the steel spigot is removed the 'ole in the head takes 3/8 gas tap perfectly -no drilling needed !

And a brass barb to suit the hose is an off-the-shelf item.
 
Quick update...for anyone interested in threads. I finally had a chance to get to Enzed and turns out that the two large holes are M16 and M18 both 1.5 pitch threads and the 3 smaller holes are M10 x 1.0 thread pitch.

So I picked up the M16 and M18 blanking plugs. However Enzed where out of stock of the M10 x 1.0 blanking plugs (i only needed one) plus the M10 x 1.0 hose barbs (i needed two) so I have ordered these online

Slowly getting there with collecting pieces for the head swap.
 
Do you have a bottom side gasket for the big bore manifold ? Doesn't a big bore manifold come with the short section of pipe at the front of the exhaust ?

I used to have a big bore gasket and could look for it...and bring it to Bastille Day if you want it.

Of course the gasket between big bore manifold and head is the same as standard.
 
Hi Beano, if you have one lying around and if you can bring it to bastille day, that will be very much appreciated.

I am fast running out time to get the head off and changeover before bastille day. I need to sort the brakes first (replace leaky master cylinder, replace leaky brake proportioning valve and rebuild all 4 calipers - new rear pistons so I can have a functioning handbrake).

From what I am learning, yes intermediate gasket is different. Gasket at the head is the same

Thank you
 
You must log in or register to reply here.
Top