[Z06] PAC 1218's
Thread Starter
Instructor
Joined: Jun 2016
Posts: 208
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PAC 1218's
I'm trying to decide between the GM blue springs and the PAC 1218.
I don't know if I'll ever do a cam. Maybe. Considering the extra pressures of the PAC springs, if I never do a cam will they just create more unnecessary stress?
The GM's are cheaper, but if I upgrade past their capabilities I'll have to get new springs anyway.
Thoughts?
I don't know if I'll ever do a cam. Maybe. Considering the extra pressures of the PAC springs, if I never do a cam will they just create more unnecessary stress?
The GM's are cheaper, but if I upgrade past their capabilities I'll have to get new springs anyway.
Thoughts?
Advanced
Joined: Nov 2016
Posts: 70
Likes: 3
I bought the GM blue springs as cheap insurance. turns out I put a BIG cam in the car a month or so later lol. I ended up doing the btr dual spring upgrade. I have some blue springs I'd sell for 50 bucks lol. like 100 miles on the at most.
Racer
Joined: Mar 2016
Posts: 437
Likes: 39
From: PA
If I was you I would buy some new LS6 springs and toss them in. I bought mine new last year for $54 shipped, I searched the part# on google until I found the best deal.
If you decide to change the cam eventually, you may prefer/need to run a dual valve spring depending on the cam selection so the 1218 beehives may not even be reusable in that sense. Plus, at that time, if that time comes, you can pull the LS6 springs and sell to someone for a few bucks to recoup the money you spent on them.
Just my .02
If you decide to change the cam eventually, you may prefer/need to run a dual valve spring depending on the cam selection so the 1218 beehives may not even be reusable in that sense. Plus, at that time, if that time comes, you can pull the LS6 springs and sell to someone for a few bucks to recoup the money you spent on them.
Just my .02
Thread Starter
Instructor
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How long have they been in? No issues due to the increased spring pressures?
Heel & Toe
Joined: Aug 2016
Posts: 18
Likes: 3
Less than 1000 miles, iirc they have similar stock pressure, I believe the next one up forgot which one was stiffer.
Thread Starter
Instructor
Joined: Jun 2016
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I went with the GM blue springs. Bought new oem seals too. New oem retainers and Comp Cams locks. TR55 plugs and GMPP red wires.
I used a 10 gal compressor, set at 90 psi. Worked perfectly! I was nervous at first though. Taking the plug wires off was the hardest part really. The seals were also slightly annoying. I also removed the alternator for more space. I was only able to get the driver side done in the time I had. Took about 3 hours. I think the passenger side will be quicker. I didn't follow to torque procedure for the rockers. I took one plug out at a time and did the springs for that cylinder. Installed new plug and wire and moved on. By the time it came down to putting the rockers on, I realized I wouldn't be able to follow procedure. I torqued them down to 22 ftlb and double checked.
I started it up, and everything sounded great. It ran perfect. Got the oil up to 127 and shut it off. I'm going to re check the torque when I do the passenger side.
Very easy swap and it was really fun!
I used a 10 gal compressor, set at 90 psi. Worked perfectly! I was nervous at first though. Taking the plug wires off was the hardest part really. The seals were also slightly annoying. I also removed the alternator for more space. I was only able to get the driver side done in the time I had. Took about 3 hours. I think the passenger side will be quicker. I didn't follow to torque procedure for the rockers. I took one plug out at a time and did the springs for that cylinder. Installed new plug and wire and moved on. By the time it came down to putting the rockers on, I realized I wouldn't be able to follow procedure. I torqued them down to 22 ftlb and double checked.
I started it up, and everything sounded great. It ran perfect. Got the oil up to 127 and shut it off. I'm going to re check the torque when I do the passenger side.
Very easy swap and it was really fun!
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Thread Starter
Instructor
Joined: Jun 2016
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Done! I double checked the torque of the driver side rockers after NOT following fsm procedure. All were still at 22. I torqued down the passenger side the same. I'll be checking them again on Saturday.
I warmed it up at idle to 123 degrees then drove it a few miles into the 180's. I took it easy mostly, although I forgot a couple of times and took it to 3k and 4k rpm's once each. Oops! the rest of my driving won't be over 2k for three cycles.
New plugs and wires seem great! Happy with the project overall, it was fun.
I warmed it up at idle to 123 degrees then drove it a few miles into the 180's. I took it easy mostly, although I forgot a couple of times and took it to 3k and 4k rpm's once each. Oops! the rest of my driving won't be over 2k for three cycles.
New plugs and wires seem great! Happy with the project overall, it was fun.