Gearing up for some more upgrades! After bugging Trent for months to sell me his manifold, I was finally successful. Also bought his cat cams, wastegate and downpipe etc.. Then I was advised to upgrade my valve springs, so I bought these from Swedish mike at Autotech. These require different retainers since Volvo changed the spring design in 99 and the upgraded springs are the newer shape (right). The early RN heads still use the 7mm valves so these are the retainers you need. This got me wondering why I can't use the solid lifters too, but i'm still trying to wrap my head around that. Based on this thread.. and this post specifically, http://forums.turbobricks.com/showpost.php?p=804652&postcount=33 it appears that some of the 6 cyl motors got the solid lifters, updated spring design but retained the cams with 32mm base circle. It wouldn't be suprising if this happened on some of the 5 cyls also. I didn't get the cams that came with the junk head I pulled the retainers from, so i'm going to try get my hands on those. If they do indeed have the same base circle, it might be worth looking more into. Otherwise I just go with my hydros and keep the rpms at 8k Solid lifter on the bottom. I ordered all new timing belt, water pump, tensioners, cam seals, valve stem seals, etc etc.. a few days ago, so just waiting for all that to arrive and then I get to pull my car back apart. Stay tuned.. Also cut up and old cam cover to use for setting the cams up.. still trying to figure that one out too, measuring lift with hydro lifters..