I know this is a beat to death topic but I am finding it very difficult to find the MP springs that are a compliment to the Cam. I've searched high and low - called MP's tech line to get help on finding such springs and to no joy - I cannot find the springs. Unless some of you have a set I can purchase then I need a little advice.
When I called the tech line they told me that the P5249464 springs may have issues with them since they have been on back order for awhile and he did not see any in production anytime soon... sooo he recomended a set that had a lift range of .480 - .600 ... same other specs- Install height 1.640, O.D. 1.42 and wire dia .187 . So the only difference was the seat pressure at 131 lbs vs 113 lbs. My engine guy said that milling the valve seat or spring seat can compensate for the pressure. I just wanted to get some other professionals opinions. The Spring in question is MP P4876062. Any help would be appreciated.
If you end up machining the seats, you can get different and cheaper springs to work anyhow - thus solving the problem. 1.70" is a pretty common install height and I think alot of SBC springs are that height. You can get sets from summit for dirt cheap. All kinds of different pressure options too. Or you can mill down the seats to accept the recommended springs for that cam (which are recommended for a 258).
On the other hand, I run the same cam and did so with the stock springs for over two years without an issue. Just didn't rev it up past 4500 or so. I now have the MP springs. I put the stock spring in a vise and at .480" lift there was still space between the middle coils, but not sure if it was enough to be safe. I don't know enough about engines to say one way or the other.
but I am finding it very difficult to find the MP springs that are a compliment to the Cam. I've searched high and low - called MP's tech line to get help on finding such springs and to no joy - I cannot find the springs. Unless some of you have a set I can purchase then I need a little advice. 