timing

I have done a search but can not seem to find what I am chasing.
what I have is a 604 with 15 to compression on metho and hat injection with ported profiler heads, now I would imagine the timing would be different to my old 557 with dove heads.
also when these people sent it over from the USA the front engine plate is only held by four bits of threaded rod that go through the water inlets, where the water pump would go, is this strong enough to hold these engines.
anyone with ideas would be great.

With the info given, you will most likely need to run the ignition timing somewhere between 32 and 35 degrees.
The motor plate must not use threaded rod. Grab the proper length grade 8 bolts and good washers.
It is a great idea to drill holes in the motor plate that match with holes in the front of each cylinder head. You can install a bolt and spacer there, removing much of the load from the 5/16" bolts.
Cheers,
Keith

thanks Kieth