Atomic Barra Billet Camshafts

We have a range of specially developed camshafts to suit the Ford Barra engines. The original profiles have short duration figures, which impedes breathing and therefore requires relatively high boost levels to achieve reasonable power levels.

Our cams are designed to produce more power by harnessing more residual exhaust gas heat, pressure and velocity to impart greater motion to the turbine, which helps develop turbo pressure more efficiently. On the inlet side, careful matching of the valve opening and closing valve events to the piston motion of the long stroke (1.55 L/R ratio) engine provides much greater cylinder filling capacity, hence engines develop considerably more power from a given boost level.

All lobe profiles are inverted flank asymmetrical designs, with a faster rate of lift to allow the passage of intake/exhaust gases more efficiently. The actual valve lifts are only increased slightly across the range to maintain valvetrain stability at high RPM.

We also reduce the OE base circle dimensions slightly to reduce lifter preload, thereby allowing the lifters to function correctly.

Due to factory machining variations in the cylinder head, all lifter preloads must be checked when installing cams to ensure preloads are within minimum and maximum tolerance.

The unique feature of many of our inlet lobe designs is our “Duo phased” timing; a split lobe centreline which opens one inlet valve before the other, introducing swirl into the combustion chamber. This also increases the effective duration of the inlet without changing manifold vacuum.

We developed this innovation in 2006 and it is interesting to note that Ford has also since introduced swirl technology into the FG engine in 2008.

Very minimal changes in manifold vacuum at idle occur following fitment of our Stage 3 and 4 cams however a noticeable lope develops in the idle after fitting our stage 4Plus and Stage 5Plus cams.

In the power department, it is not uncommon for engines to produce an additional 30-50 kW of power at a given boost level following the fitment of our cams (and retuning).

For the serious power junkie, we have attained 760KW at 35 psi boost with our Stage 4Plus cams.

Working with our high volumetric efficiency Stage 5Plus cams we have recorded over 570 RWKW at only 22 psi boost and 1133RWKW at 49 psi boost, achieved with our own vehicles.

Installation instructions.

1. Remove turbo ducting to gain access to rocker cover. Remove cover, spark plugs and coil packs to gain access to valvetrain.
2. Rotate engine until yellow timing marks on timing chain line up with marks on VCT units and then loosen VCT retaining bolts - do not remove at this stage.
3. Mark the 4 camshaft saddles as D/side front, D/side rear, Pass/side front and Pass/side rear, then loosen retaining bolts and remove saddles.
4. Mark VCT units as driver’s side and passenger’s side, then remove. Secure the timing chain against the side of the timing cover with a piece of wire. Please note the timing chain tensioner will engage fully at this time; however it can be easily reset later.
5. Mark the original camshafts as inlet and exhaust whilst they are still fitted in the engine.
6. Remove the inlet cam first and compare it against the new cam to ensure cams are identical. This is best performed by noting the positions of the cam position trigger located on the on the rear of the cams.
7. Repeat this checking with the exhaust camshaft.
8. Measure the bearing journals of the cams being removed and compare against the new cams – the new cams must be within .001” of the original camshaft diameters. We have noted a lot of variation in factory camshaft tunnel/cam sizes, so pay particular attention to these sizes. In some cases it may be necessary to reduce the diameter of the new cams’ journal to match that of the cam being removed.
9. Check and inspect the condition of the roller followers for signs of wear and replace as necessary.
10. Check valvespring tensions and replace any weak springs with suitable replacement springs as required.
11. Reinstall the new camshafts and VCT units after applying a liberal coating of engine oil to all contact surfaces.
12. Reset the timing chain tensioner to the fully retracted position paying careful attention the timing marks on the VCT units are lined up correctly with the timing chain, and the correct cams are fitted in the correct locations.
13. Release the timing chain tensioner by pulling upward on the locking tab with a small hooked tool.
14. Continue to reinstall the rest of the components and torque all bolts to the factory specifications.
15. To verify the timing marks are correctly lined up, rotate the engine until the timing marks come back around and correspond with the VCT units. Be patient, as the motor must be rotated 36 times to allow the timing chain to return to its original position.
16. Reinstall the rest of the engine accessories and double check all bolts, clamps, etc are tight. Restart engine and hold at an idle speed of 1000-1400 RPM for 10 minutes.

Important notes.

• Engine will require tuning to get the maximum benefit from the camshafts’ extra breathing capacity.
• If the vehicle is driven any great distances before tuning is carried out the OBD system may log a fault code due to the new camshafts altering the engine vacuum. If this occurs the code can be reset by the tuner.
• The camshafts do not require any run in period.
• Ford lifters can take up to 45 minutes of running before they bled up correctly – be patient and keep the engine RPM low unit all clearance is take up by the lifter.
• If you have any questions, please do not hesitate to call us – we are here to help!!

The Team at Atomic