Race Engine Forum UK

Hello Guy,

I have bought a Hoermann Rallye Camshaft.
The data's:
Inlet 11,3mm - Exhaust 8,3mm Lift
Inlet 26‚°/66‚° - Exhaust 67‚°/41‚°

Today I have written the lift on paper every 2,5‚°.
But here must be some wrong because the Inlet valve (German "Einlass") closes when the exhaust valve opens...
Do I have a wrong deg pulley?
I have add a picture how I have measured it.
I know that my degree's are wrong because I must add 180‚°.
I had fitted the standard cambelt pulley from the 1.3 turbo and I had set the tdc of the degree pulley on the mark of the tdc (to know if the standard pulley is right) but I had fitted the gauge on the wrong site (about the camshaft and not under like in the engine it is... I hope you understand!).

Thanks for helping.
The main problem is, Hoermann doesn't have a data's for the camshaft and I need the lift in tdc to install this cam :(

Before asking, Yes I know what it means to drive this camshaft. It's rallye camshaft from Italy. Maybe a "Group" camshaft...

I have found the fault :)

The degree pulley is the wrong way round.
The offset is no problem because the camshaft makes a half round when the crankshaft makes a round.

When I reflect the curve all must be fine, or?

It works :)

Thanks for you time ;)

Just for a check Acki

Inlet 26‚°/66‚° - Exhaust 67‚°/41‚°

(All figures are crank degrees (twice cam deg))

Inlet duration is 272 deg
Ex duration is 288 deg

Overlap period is (26 + 41) = 67 deg
Inlet full lift is 110 deg ATDC
Ex full lift is 103 deg BTDC
Lobe centreline angle 213 deg

In case you don't know - you need to degree-map these cams with a bucket (flat follower) in a cam housing, not with the dti gauge straight on the cam profile. The timing figures you gave (from the maker) depend on the clearance they are measured at - could be anything from zero (with flat follower) to 0.5mm. If you don't know that clearance figure you cannot compare the timing figures with the ones you measured. If you measure with zero clearance & the manufacturer used 0.4 inlet and 0.45mm ex (for example) your durations are going to look much longer than his.

GC

Thanks Guy.
The clearance is 0,3 inlet and 0,35 exhaust :)

I have set the tdc ~13‚° after the inlet begins to open (in this point the lift is 0,31mm at 347,5‚° and so that are 12,5‚°).
I think I must test a little bit with the camshaft (1,2,3‚° before and after the point I have found now).
But I need this curve for making my pistons for the valve "pockets" (?) and there is a little safty... maybe you can help me?

After the curve the lift in tdc is 1,29mm - 0,30mm = 0,99mm.
I think 1mm is correct.

I hope my englisch is not too bad :(