Author Topic: Valve springs?? (Read 2978 times)

littleboyblues · « **on:** May 12, 2009, 09:24:39 PM »

I'vs heard of people putting s52 valves into there m42's because there better... However, i've also heard that the m50 non-vanos valves are the stiffest out of all the m5x engines. Is this valve better then what we have in the m42??

halcrontech · « **Reply #1 on:** May 17, 2009, 10:54:32 AM »

I have no idea if S52 valves could fit into M42. But you could go for Supertech valves as well.

dsm2002 · « **Reply #2 on:** May 17, 2009, 06:58:25 PM »

I doubt the S52 would fit. The valve is much longer. In the Supertech catalogue, the M42 and M52 use the same spring. No idea, however, if there are differences in stock valve springs for vanos vs non-vanos.

Remember that the stiffest spring is not always the best. The spring must be just stiff enough for given revs/cam/valve train combo. Too stiff increases wear and friction for no benefit. What cams will you be using?

littleboyblues · « **Reply #3 on:** May 18, 2009, 05:39:15 PM »

Well i was just wondering if the m50 valves would work. The non-vanos valves are supposedly slightly stiffer than vanos, nothing crazy stiff. I was just wondering if they'd fit. Its a juckyard pull thats mad cheap:)