engine identity?

Hi guys,

had my 4.6 for a year now , was told it had an rpi engine in it but the guy couldnt produce proof but I still had it without paying over the odds. It developed a loud rattle and I took it to my mechanic, who said it was the cam. I asked if it could be a slipped liner and he was sure it wasnt. I have had an rpi cam kit fitted and it still rattles like a bitch. Checked the engine number and its defo a replacement but not sure if its coscast. Trying to find out to see how to progress. The engine numbers first number is slightly obscured by the exhaust manifold so it either starts with 687D, or 887D or 387D. If its not coscast, what are the other options.

cheers guys

Phone RPI ?

will be tomorrow, but there doesnt seem to be a coscast logo on the block so wondered if there is another popular replacement

Bugger, its not an RPI , but engine number is not a genuine RR one, but cant trace it to where it came from. So just spent a load getting the cam kit changed for no reason grrrr, now to decide whether to spend a load more on a new block or more to the point can I raise the money or am I going to be forced to sell/scrap my beauty