AJP 4.5 Timing

[Fex2005]

Morning, I am currently giving my Cerebera a bit of a overhaul (Normal chassis works etc), and almost ready to get her back on the road however run into a bit of a wall. I'm currently getting an engine rebuild (AJP 4.5). The engineer working on the engine is a race car/performance car specialist (Porsche) and is in the final stages and is into setting up the engine timing.

The TVR engine workshop manual seems to mention a process that involves a custom timing cover (basically a standard one chopped in half). Not sure why this is the case as in every other car you just get the timing settings and set it from that.

Does anyone know where to locate one of these modified timing covers (purchase or borrow), or if an existing one could be modified to suit?

Also, am I missing something can the timing not be set as normal if The settings are available? The way described seems to be a long winded, pain in the ass method of setting the timing.

Any help/advice from how others have handled this would be appreciated.

[Jhonno]

All it is, is to stop the sprockets falling off iirc.. You could achieve the same with a plate.

[TwinKam]

It is pretty normal for a comp engine to have its cam timing set by a specified amount of valve lift at TDC, rather than lining up marks/pegging sprockets. Thankfully the AJP has only one camshaft per bank to time.

[plasticman]

As there are no timing marks on the AJP it is probably better if you put some on yourself but you will need to have an engine with a pulley for the air con. I attach a pointer to the timing cover then mark TDC for each bank on the pulley. If cylinder 1 is at TDC then set 1 or 7 to equal overlap on the bucket followers ( sitting at the same height ) . Repeat with the even bank with cylinder 2 at TDC . I know the factory recommends a bit more advance than this but from memory was recommended by Jools and is very easy to set .

[ukkid35]

plasticman said:

As there are no timing marks on the AJP it is probably better if you put some on yourself but you will need to have an engine with a pulley for the air con. I attach a pointer to the timing cover then mark TDC for each bank on the pulley.

No marks on the pulley in that pic, but you get the idea

[ukkid35]

Jhonno said:

All it is, is to stop the sprockets falling off iirc.. You could achieve the same with a plate.

As Dan says, all you need is a plate with holes in the right place. I'm away from home atm otherwise I could include a pic.

[ukkid35]

You might find these helpful

https://www.pistonheads.com/gassing/topic.asp?t=16...

https://www.pistonheads.com/gassing/topic.asp?t=11...

[Fex2005]

thanks all, the information provided has been helpful, i now understand a little bit more.