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[fcc-pt]

The GM 54º X30XE seems an even firing interval engine since its fire order is 1,2,3,4,5,6. I think it must have a 60 degree firing interval if so it must have an unshared crankshaft with the correct offset of 6 degrees missing from the 54 degree bank angle.

I need to know how to time the engine after remove the heads. I suppose I need to place piston 1 at TDC and look for crankshaft mark of TDC right?

About the heads what’s the procedure?

[Nick W]

The procedure is to use the cam timing tools. LINK


That's everything to do the job; tool to position the crank, locks for each pair of cams, torx socket for the crank bolt, wedge to hold the belt while you thread it around the pulleys, cranked 30mm spanner for the adjusters and the gauge to ensure that each pair of cams is correctly aligned.


You install the heads with the pistons before TDC to ensure they're down the bores. Then you fit the heads, torque them, fit the cams, add the locks using the gauge and turn the crank so its tool locks against the water pump. After that it's the usual belt replacement procedure.

[fcc-pt]

I've that tool kit bought that a couple months ago...
I've taken the admission and head valve covers, work in progress!

Just a stupid question, how do I ensure that the cams are at the right stroke phase?
Whats the ratio between crankshaft / camshaft rotations?

[Nick W]

I've that tool kit bought that a couple months ago...
I've taked the admission and head valve covers, work in progress!

Just a stupid question, how do I ensure that the cams are at the right stroke phase?
Whats the ratio between crankshaft / camshaft rotations?

The ratio is 2:1, crank:cam just like any other four stroke engine. Each cam pulley has twice the number of teeth that the crank pulley does to achieve this.


The cam pulleys are marked for each pair and for inlet or exhaust. The dowels are offset to fit them correctly. There are marks intended for each of these to be used with the timing gauge. You align the marks on the pulleys with the marks on the gauge and fit the locks. You don't have to measure or calculate anything.

[fcc-pt]

I've notice that the camshaft dowel is aligning with pulley numbers 1,2 for the left head and 3,4 for the right head (standing in front of the car).
Concluding that I need 720 degree rotation for crankshaft and 360 degree rotation for camshaft.
I've also found the marks in pulleys are quite different in both heads this is a bit tricky but marks are related with inlet and outlet guessing.
 





 

[Doctor Gollum]

That's why you use the tools

Haynes manual also covers most of the details.

The block V angle is irrelevant.