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DISCUSSION => Engine + Driveline => Topic started by: sh123 on October 14, 2016, 03:49:48 PM

Title: Cam regrinding
Post by: sh123 on October 14, 2016, 03:49:48 PM

Hi

Just looking for some info.

I cant get my head around how regrinding a cam works.

Surely if a cam is ground you will loose something somewhere.

Keep on hearing people saying theyve had cams reground to race spec at 300deg duration etc.

So if i have a standard m44 cam. 240deg 9.5/10mm lift ish?

Would it be possible to get a copy of metric mechanics rally cams which are 280deg and 11.5mm lift?  Where would the trade off be if any?

Sion

Title: Re: Cam regrinding
Post by: Darky on October 15, 2016, 06:06:09 PM

Cam regrinding is a process where they first rough up the smooth cam surface then weld more material to the surface making the lobe bigger then grind the surface smooth again.

Advantages are is that it is relatively inexpensive.
Disadvantages are if the built up welded on lobe breaks off then that partular valve might 1. Be Stuck in up  2. Be stuck in down position.
Which can cause significant problems

Valves and pistons might argue!