Which pulley did you go with?
Valve Springs
Thread Starter
Pro
Joined: Jan 2006
Posts: 541
Likes: 38
From: Temecula CA
Valve Springs
Just got my car back last week from having an A & A Si kit installed and the car runs really well, although I must say that I am a little disappointed with the power it made on the dyno. Car made 474 hp before encountering valve float. My tuner is recommending I install the 2004 ZO6 valve springs on the motor, which I believe are yellow and carry GM part #12586484. They are certainly cheap enough, and the install cost isn't bad, so I was wondering if anyone here is running them on their LS1 and how much rpm and horsepower they gained. If not these springs which ones would you recommend for my combination?
Phil
Phil
Racer
Joined: Aug 2006
Posts: 399
Likes: 82
From: Terre Haute Indiana
Pass on the gm springs...put some PAC 1218's (single .600 max) or 1215's (double .650 max) on them. I think I paid $140 plus shipping.
Had the same issue on mine. Put 491 down....swapped out the springs with the 1218's and made 578 afterward.
Had the same issue on mine. Put 491 down....swapped out the springs with the 1218's and made 578 afterward.
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 77
From: Forney Texas
The horsepower is directly proportional to RPM (Tq*RPM/5252), so don't worry. Replace the springs and the numbers will follow. I'm with the rest of the crowd. The GM springs are insufficient for your supercharged application. Patriot duals are probably the most popular and the best bang for the buck IMO.
Thread Starter
Pro
Joined: Jan 2006
Posts: 541
Likes: 38
From: Temecula CA
I'm running the stock pulley. It is pinned. I am somewhat surprised that the valves started to float at 5200 rpm, given that the motor has less than 14,000 miles on it.
Thanks for the tips guys.
Not really interested in used springs, but thanks for the offer. Only question left now, is whether to go with the 1218's or the 1215's.
Phil
Thanks for the tips guys.
Not really interested in used springs, but thanks for the offer. Only question left now, is whether to go with the 1218's or the 1215's.
Phil
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Pouria Savadkouei
AKA "The CLOWN"
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From: Chicago South Suburbs
Thread Starter
Pro
Joined: Jan 2006
Posts: 541
Likes: 38
From: Temecula CA
10 psi of boost drops effective spring pressure by 28 lbs? First I've heard of that. The stockers are only 76# closed and 220# open so that is a big impact! It would certainly explain things. Guess, I better get those springs pretty soon.
Blitzkrieg,
OK, I'm interested in the 918's but am wondering, why did you remove them from the car after the dyno runs?
Also, anyone else running these springs? Are you happy with them?
Phil
Blitzkrieg,
OK, I'm interested in the 918's but am wondering, why did you remove them from the car after the dyno runs?
Also, anyone else running these springs? Are you happy with them?
Phil
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 77
From: Forney Texas
Safety Car
Joined: Apr 2000
Posts: 4,326
Likes: 140
From: Weatherford, TX
Here are the 918s before I pulled them. Right now they're in a bag with retainer caps and valve locks. They appear to be compatible with stock seals, so those don't have to be changed. Let me know if you want them.
Thread Starter
Pro
Joined: Jan 2006
Posts: 541
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From: Temecula CA
Hi Chris,
OK, I'll take them. Not clear what I'm buying though. Are you talking the springs, retainer caps, and clips for $100, or just the springs? Did some research and they are indeed compatible with stock valve stem seals and retainers.
Phil
OK, I'll take them. Not clear what I'm buying though. Are you talking the springs, retainer caps, and clips for $100, or just the springs? Did some research and they are indeed compatible with stock valve stem seals and retainers.
Phil