BBC Spring Locator Cups Question?

Tgreen3724 · 06-02-2015, 11:15 AM

running a BBC cast iron head (casting 188) with Comp 947 springs and in order to clear the rocker arms I need to reduce stack height by .045. To get my stack height back should I remove the locator cups completely and just run the springs on top of a .015 shim or should I machine .045 off of the bottom of the locator cups (leaving .015 of thickness). Without cups I have approx. .105 of clearance between the ID of the inner most spring and the od of the valve guide. I do not run seals so clearance between spring and seal is not needed. What are your all thoughts?

Mike Taylor 3601 · 06-02-2015, 02:02 PM

To gain more clearance between retainer and rocker,are you planning on using a -.050 lock which reduces installed height and then removing spring seat or machining it to gain the .050 back in installed height?
If i was doing it and had the room to set spring installed height .050 less I would just put the -.050 lock on it and run more pressure.
If don't have the room,if head will locate spring take spring locators/seats out and use .015 shim.
Mike Taylor 3601

TurboBuick6 · 06-02-2015, 02:59 PM

Sounds like you have .560 guides. We do offer a .030" thick spring seat for those springs. Depending on installed height, you may be fine running the -.050" locks and our .030" tick ID locators.

Tgreen3724 · 06-02-2015, 05:58 PM

If I can reduce stack height by .045 then my distance to coil bind becomes .064 if I tried .030 I would only have .049 which wouldn't be enough. Thanks for the suggestion though

TurboBuick6 · 06-03-2015, 09:46 AM

No problem. I would like to say, you are way better off machining the heads. With the amount of ID and OD clearance you will have, I would not trust that spring on a flat shim. Too much movement available.

Mike Taylor 3601 · 06-05-2015, 07:48 AM

Don't cut spring pocket any deeper.
Mike Taylor 3601

06-02-2015, 11:15 AM	#1
Tgreen3724 Junior Member Join Date: Oct 2007 Location: Shepherdsville, Ky Posts: 38 Likes: 0 Liked 1 Time in 1 Post	BBC Spring Locator Cups Question? running a BBC cast iron head (casting 188) with Comp 947 springs and in order to clear the rocker arms I need to reduce stack height by .045. To get my stack height back should I remove the locator cups completely and just run the springs on top of a .015 shim or should I machine .045 off of the bottom of the locator cups (leaving .015 of thickness). Without cups I have approx. .105 of clearance between the ID of the inner most spring and the od of the valve guide. I do not run seals so clearance between spring and seal is not needed. What are your all thoughts?

06-02-2015, 02:02 PM	#2
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,364 Likes: 342 Liked 283 Times in 98 Posts	Re: BBC Spring Locator Cups Question? To gain more clearance between retainer and rocker,are you planning on using a -.050 lock which reduces installed height and then removing spring seat or machining it to gain the .050 back in installed height? If i was doing it and had the room to set spring installed height .050 less I would just put the -.050 lock on it and run more pressure. If don't have the room,if head will locate spring take spring locators/seats out and use .015 shim. Mike Taylor 3601

06-02-2015, 02:59 PM	#3
TurboBuick6 Junior Member Join Date: May 2014 Posts: 26 Likes: 0 Liked 0 Times in 0 Posts	Re: BBC Spring Locator Cups Question? Sounds like you have .560 guides. We do offer a .030" thick spring seat for those springs. Depending on installed height, you may be fine running the -.050" locks and our .030" tick ID locators.

06-02-2015, 05:58 PM	#4
Tgreen3724 Junior Member Join Date: Oct 2007 Location: Shepherdsville, Ky Posts: 38 Likes: 0 Liked 1 Time in 1 Post	Re: BBC Spring Locator Cups Question? If I can reduce stack height by .045 then my distance to coil bind becomes .064 if I tried .030 I would only have .049 which wouldn't be enough. Thanks for the suggestion though

06-03-2015, 09:46 AM	#5
TurboBuick6 Junior Member Join Date: May 2014 Posts: 26 Likes: 0 Liked 0 Times in 0 Posts	Re: BBC Spring Locator Cups Question? No problem. I would like to say, you are way better off machining the heads. With the amount of ID and OD clearance you will have, I would not trust that spring on a flat shim. Too much movement available.

06-05-2015, 07:48 AM	#6
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,364 Likes: 342 Liked 283 Times in 98 Posts	Re: BBC Spring Locator Cups Question? Don't cut spring pocket any deeper. Mike Taylor 3601