BTR Dual spring installed height / pressure specs sound right?
#1
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
First up I have done a search and can't seem to find a definite answer.
I have just had my machine shop dismantle, clean and install my new springs and seals on my LS1 (241) heads. He thought the springs might have too much pressure, so I am hoping someone here can let me know if these specs sound about right or something has gone wrong.
The springs I am using are BTR Dual Spring kit with Titanium retainers (Part: BTR #SK001). The heads are factory, have not been milled.
Specs machine shop has given me are;
175lb @ 47.2 Installed (I am assuming this is mm, which works out to 1.858")
380lb @ 0.500" Lift
Any help would be greatly appreciated.
I have just had my machine shop dismantle, clean and install my new springs and seals on my LS1 (241) heads. He thought the springs might have too much pressure, so I am hoping someone here can let me know if these specs sound about right or something has gone wrong.
The springs I am using are BTR Dual Spring kit with Titanium retainers (Part: BTR #SK001). The heads are factory, have not been milled.
Specs machine shop has given me are;
175lb @ 47.2 Installed (I am assuming this is mm, which works out to 1.858")
380lb @ 0.500" Lift
Any help would be greatly appreciated.
#3
TECH Senior Member
iTrader: (4)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Based on the specs provided by DietCoke, I get a stiffness of 377 lb/in. I get an installed height of 1.727" or 43.86 mm.
In my experience with 241 heads, they won't set up at 1.858" unless the valves have been sunk deeper into the head. Stock they set up around 1.76".
What was done to the heads?
In my experience with 241 heads, they won't set up at 1.858" unless the valves have been sunk deeper into the head. Stock they set up around 1.76".
What was done to the heads?
#4
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Thanks for the reply's. The heads were just dismantled, hot tanked and reassembled with the BTR spring kit. Is there anything that could of been done wrong, anything I can check if I take them back off and re-install?
#5
TECH Senior Member
iTrader: (4)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
You could pull two springs and check installed height. Simple to do but you do need a valve spring compressor and a valve spring micrometer. If the valves weren't ground then the installed height should remain as stock. Also, if you really want to disassemble, I would lap the valves if that wasn't done.
It appears you are in Australia, correct? That is why he probably gave you the installed height in mm.
It appears you are in Australia, correct? That is why he probably gave you the installed height in mm.
Last edited by vettenuts; 02-29-2016 at 06:20 AM.
#6
FormerVendor
iTrader: (13)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
We get this call weekly. We have machine shops getting anywhere from 1.660"-1.880" installed height and anywhere from 120 lbs to 200 lbs on the seat.
Our retainers have less than .010" variance in installed height and less than 10 lbs variance on seat pressure.
The bottom line is, if your machine shop installed them as is with no shims, you're good to go. If they installed shims then you should probably remove them.
Our retainers have less than .010" variance in installed height and less than 10 lbs variance on seat pressure.
The bottom line is, if your machine shop installed them as is with no shims, you're good to go. If they installed shims then you should probably remove them.
Trending Topics
#8
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Thanks for the replys and very helpful info, feel a lot better bolting the heads back on now. The machine shop has not used any shims so should be good to go, will post up some pics tonight of the spring installation. Yip i'm in Australia.