© Copyright 2011 safire associates
four port manifold air intake modification

Aluminium engine intake manifold modifications

aluminium 4 port manifold Aluminium plenum chamber

After

Before

At Safire as well as waterjet cutting we get involved in projects that use multiple skill sets from our range of in house facilities...

We were approached by our customer who is a car enthusiast to assist in modifying his aluminium engine parts, the basics of the work was to modify the Air intake manifold and plenum chamber to a higher specification. My customer had obtained the know how and drawings from the Internet and he asked us to perform the work as it was beyond his workshop and skill capabilities. Pictured above is the basics of the work on the left top you can see the aluminium manifold and below that the plenum air intake chamber and in the picture on the right you can see the finished parts roughly assembled.

So what did we do for the project:

rough assembly of the modified intake manifold

New carburettor mounting plate This was Waterjet cut from 10mm aluminium plate  drilled and tapped

New spacer plate water jet cut from 40mm thick aluminium

New gaskets water jet cut from 2mm thick polypropylene

New manifold plate waterjet cut from 10mm thick aluminium

All parts were Vapor blasted after the work was complete to clean up an make a nice finish.

The end of the old plenum chamber was removed and the new carburettor mounting plate was aluminium Tig welded in place and holes were threaded

Old manifold inlet ports were shortened and the new manifold plate was aluminium tig welded in place, then skimmed on a milling machine and port entries were machined with a smooth radius and holes were threaded

Main parts:

laid out on the table are all the parts, at the top of the picture are the waterjet cut parts consisting of a 40mm thick aluminium spacer plate, a 10mm thick aluminium manifold plate, a 10mm thick carburettor mounting plate and two 2mm thick polypropylene gaskets to go either side of the 40mm thick aluminium spacer plate
Waterjet cutting is an excellent way to profile cut all metals and their alloys and it is excellent for cutting Aluminium plate, leaving a clean burr free edge. The polypropylene also cuts very well, leaving a slight burr that needs to be scraped off after.
At the bottom of the picture is the plenum chamber, the inlet manifold ready for modification.
Note the dirty appearance of the original parts prior to the vapour blasted finish.
all the manifold parts laid out on the bench New aluminium manifold plate test fitting removal of the old intake port on the plenum chamber
What was involved in modifying the aluminium engine air intake manifold:
Aluminium air intake manifold modification:

After the manifold adaptor plate was waterjet cut from 10mm thick aluminium plate we did a test fit over the manifold inlet ports to make sure it fit perfectly.
In this case out customer supplied the cad files for the plate and they were good dimensions but we then reduced the tolerance to 0.2mm clearance for the best fit onto the inlet ports as this nice fit would make a better job on the Tig welding.
After checking that the plate fitted snuggly over the manifold inlet ports. the inlet ports were marked and then cut down so they were just over 1mm above the new plate surface, ready for tig welding.
Plenum chamber modification:

The plenum chamber was marked off for the removal of the old inlet port and we cut the end off as accurately as we could. A lot of care was required here as we needed the end to be as clean and square as possible ready for the tig welding of the new carburettor plate that was to be fitted on the end.
Note the dirty aluminium  and corroded surface of the plenum chamber, this came up very well after vapour blasting, see the finish we achieved in the finished pictures further down on this page.
the finished parts for the aluminium engine intake manifold 40mm thick aluminiun spacer plate air intake manifold modified with new 10mm thick aluminium plate close up of the machined manifold intake port
The finished parts for the aluminium engine intake manifold:

40mm thick spacer plate

Plenum chamber modification

Inlet port modification

Polypropylene gaskets

40mm thick aluminium spacer plate:
The spacer plate was water jet cut from 40mm thick aluminium plate, this is designed to sit in between the manifold plate and the plenum chamber to add more volume in the chamber.
It is pictured with a steel rule to show the 40mm thickness and to give you a sense of scale
Aluminium manifold plate modification:
The new manifold plate was waterjet cut from 10mm thick aluminium plate, then it was fitted over the inlet manifold ports after they have been reduced to approximately 1mm above the new manifold plate. The manifold plate was chamfered out to allow good aluminium Tig weld penetration. The new manifold plate was then fully tig welded on around each inlet port.
After welding we skimmed across the full surface face on a milling machine to set it parallel with the opposing face, the inlet ports then had a radius machined all round to take of the sharp edge and to assist in air flow through the ports.
The holes were all tapped ready for assembly
modified plenum chamber carburetta manifold mounting plate tig welded onto the plenum chamber carburetta manifold plate
Plenum Chamber Modification:
The plenum chamber modification consisted of the cutting off the end of the old inlet port, and tig welding a new Aluminium carburettor mounting plate waterjet cut from 10mm aluminium plate.
The plate was tapped for the required bolts and the plate was fully aluminium tig welded on.

10mm carburettor mounting plate fully tig welded on

Threaded / tapped holes

What can we do for you?

a modified plenum chamber roughly assembled the finished modified plenum manifold assembly
The finished assembly
At Safire we can conceptualise, design, fabricate, machine, waterjet cut etc....
All in house here in Southampton England
Here's a couple of close up shots of the new carburettor manifold plate tig welded to The plenum chamber.
safire waterjet about us safire water jet project gallery safire water jet location safire water jet request a quote
© Copyright 2011 safire associates
SubScribe 8-)

Quick contact