Some important verifications…

I’ve put some children’s modeling clay on the top of the piston in TDC to measure:

-Squish area thickness (1,7mm)

-Valve distance to piston (minimum 1,5mm) ~5mm inlet, ~4mm exhaust

Exhaust valve impression

Inlet valve…

Work in progress!

Measuring parts

Before replacing any parts, I’ve measured the parts to assess what I needed…

Ford’s tolerances: 47,64 to 47,66mm

That’s 5,17mm of cam lift (should be 6,13…)!

Performance parts

Since my budget is very limited, this section is quite small…

Schrick camshaft kit, with new valve springs and lower valve spring retainers

Cam info: 288º inlet/ 280º exhaust (28º-80º, 69º-31º)

Cam lift: 6,5mm (10,6mm at the valve)

Valve lift at TDC: 1,4mm, 1,8mm (important for good idle at low speed and the ability to pass in emissions test) below 1,9mm for 2 valve engines with hydraulic followers.

Very good machining (CNC), tight fit in head and lobes coated to aid break-in.

For those of you that never heard of this company, they are the makers of the Bugatti Veyron’s engine block and cylinder head (as many precision parts for F1, etc.)

Here’s one thing you don’t see everyday on a CVH cam, a hole in each lobe to lubricate the follower… Very nice!

The new valve springs are approximately the same geometry as the old ones.

3,5mm spring retainer and guide

Part mods…

Continuing the porting started a year ago…

When I was porting the head, I left it outside over a towel… The dog pulled the towel and head on floor!!!

After the 2nd resurface, clean valves…

As the valve seats were a bit deep into the head, there was a very sharp step between the cc and the valve seat, so I’ve machined it to prevent flow losses.

Inlet port straightned also slightly enlarged.

Exhaust port roof raisened.

Inlet valves after a 2 angle regrind, 45º seat and 30º above it.

The left one was polished with 50 grit sandpaper, then 280, 600 and finally 600 with WD-40.

Same treatment here… I’ve polished them not in search of more hp, but to prevent carbon adhering so easily.

Same thing to the exhaust valves… Not so polished because the steel is much harder compared to the inlet.

Note the lightened piston. I’ve managed to take 4 grams out but it still remained to heavy compared to rest of the pistons (weight in grams with the gudgeon pin)…

I’ve put them in order so that the rotating equilibrium is not very disturbed by different piston weight’s (not the order in the pic…)

About 600g were taken out of the flywheel (400g near the ring gear)

Ground and polished crank (fillets respected)