I’m looking to buy some slightly different followers for a couple of projects.
Ideally they need to be long skirt with 0.220" (standard) pad followers and I also require some long skirt ones with 0.246" thick pads.
I have seen the long skirt with 0.246" pad followers for sale but can’t find any long skirt with 0.220" pads.
I’m looking for the steel type not the original cast iron type.
Depth and thicknesses are approx but around those figures would be great if possible.
I think QED only do long skirt thin pad (0.160") followers from previous calls with them. I will give them a call next week but if anyone knows differently that would be helpful.
Can anyone point me in the right direction please?
Curious as to what sort of project requires a long skirt and thick pad followers? Normally a long skirt is used because you are using a small base circle high lift cam which also normally requires a thin pad to fit in the longer spring and valve stem ?
I get my valve train components from Tony Ingram in the US but there must be a suitable UK source for what you need if they exist
The head is using 420 cams and has plenty of room for full lift with Cosworth springs at acceptable installed spring lengths and pressures. Plenty of room with standard length valves and no clash between retainers and valve guide tops.
Valves are sat sufficiently into the head to avoid clash with the cams chosen.
Long skirt followers will add a bit more staibility to the valve train and won’t bottom out anywhere.
The head was done by an engineer that has a fair amount of twincam experience.
I might contact Tony Ingram and see what he can offer if I get no luck closer to home. Cheers.
What size base circle are the cams ? Personally I would only worry about needing a a long skirt follower if the base circle is below around 1.12 inch. I certainly helps to have a longer follower if it fits, but if you cant find one and your base circle is large enough I would not worry.
By my rough calculations the 0.380" cams usually come in at around 1.120" base circles so for 0.420" and 1.120" base circles it would potentially mean trimming the follower sleeves to avoid cam nose contact. I want to avoid trimming if possible as that plays into effectively shortening the followers working area (i know it’s miniscule but every little helps).
I’ve done some calculations on what works around the cam nose positions for different cam lifts, base circles and desired followers.
What base circles are you using with 0.420" lift and beyond?
I normally use 1.05 inch base circle for the 0.440 to 0.460 inch lift cams with thin long skirt followers. I use 1.00 base circle for 0.490 inch lift
Some times the scallops in the sleeves need enlarging or deepening but not always as this varies somewhat from head to head, maybe due to previous sleeve replacements. Cam lobe position can also vary a little depending on the casting especially with new cams