Why do no one use the 26915 valve spring?
Why do no one use the 26915 valve spring? They are rated to .625 lift
They are not as stiff as the 918's -- allows for easier movement of valvetrain
and they cost just a tad bit less.
What is wrong with them?
their spring rates are about 20lbs less at seat and open compared to a 918
They are not as stiff as the 918's -- allows for easier movement of valvetrain
and they cost just a tad bit less.
What is wrong with them?
their spring rates are about 20lbs less at seat and open compared to a 918
With aggressive lobes they can't control the valve train. It's my understanding an XE-R or similar fast ramp is something they can't handle. I think they were offered on some Stage I stuff a while back but they limited cam selection.
To tell you the truth.. This pisses me off.. I cant believe they still sell those springs and advertise up to .625 lift. Those exact springs were recommended to me by Comp Cams back when I had the T1 cam. Those springs did not last a week on .558 lift. When they were pulled out I sent them back to Comp Cams and they were suppose to test them and I never heard back from them until I called. The response were we are testing a bunch of returned springs right now and we will get back with you. Then finally the springs were sent back to me reporting that there is nothing wrong with the springs. You could squeeze the springs with your hand and compress them easily. The stock springs I took off my car were harder to squeeze. Richie and Tim told me to put some CC941's on the car and I never had another problem. I recommend going duals if you can. Its better to be safe than sorry. Sacrificing a possible 5 hp for more peace of mind is my best advice. LS1's will punish you if you take shortcuts.
Weeelllllll.... heheeh... My g/f has '915s on her car, with a Comp XE-R 224/224 .581/.581 112 ... It pulls to 6600 with ease, no valve float (nice, steady, even dyno curve with the smoothing on 1) .. The 915's are the exact same wire as the 918's, just wound a little looser.. Heck, I'm running 918's on a 238/240 .605/.609 112 XE-R in my car, and it holds the valves out past 6800... I'm kinda nervous about them being in there, but so far so good (knock on wood).
Both sets of springs will be replaced at some point, I wouldn't say I'm exactly COMFORTABLE with them, but they HAVE survived about 30k miles in each motor -- and they do what they're supposed to..
Both sets of springs will be replaced at some point, I wouldn't say I'm exactly COMFORTABLE with them, but they HAVE survived about 30k miles in each motor -- and they do what they're supposed to..
TECH Junkie
Joined: Dec 2001
Posts: 3,242
Likes: 0
From: Lakeland, FL
Originally Posted by Brains
Weeelllllll.... heheeh... My g/f has '915s on her car, with a Comp XE-R 224/224 .581/.581 112 ... It pulls to 6600 with ease, no valve float (nice, steady, even dyno curve with the smoothing on 1) .. The 915's are the exact same wire as the 918's, just wound a little looser.. Heck, I'm running 918's on a 238/240 .605/.609 112 XE-R in my car, and it holds the valves out past 6800... I'm kinda nervous about them being in there, but so far so good (knock on wood).
Both sets of springs will be replaced at some point, I wouldn't say I'm exactly COMFORTABLE with them, but they HAVE survived about 30k miles in each motor -- and they do what they're supposed to..
Both sets of springs will be replaced at some point, I wouldn't say I'm exactly COMFORTABLE with them, but they HAVE survived about 30k miles in each motor -- and they do what they're supposed to..
damn 30k on that kind of lift holy shiiiit! You probably better go ahead and swap those 918's out.
Yeah I know, I'm on borrowed time 
The big cam hasn't been in there all that long -- maybe 2000 miles so far.. But these springs (WAY WAY pre-blue stripe BTW) have been off the heads once for a valve job, and are working on their third cam.. First was a 221/227 .561/.569 for 23'ish thousand miles, then a 224/224 .581/.581 for another 3k or so, and now the 238/240 .605/.609 for the last 2k .. Not quite 30k on mine, but enough miles to say the "test" period is over... 
I'm looking at changing the heads here once I squeeze the current setup to its fullest, to see just how much head technology has advanced since I got these back in 2000.
The big cam hasn't been in there all that long -- maybe 2000 miles so far.. But these springs (WAY WAY pre-blue stripe BTW) have been off the heads once for a valve job, and are working on their third cam.. First was a 221/227 .561/.569 for 23'ish thousand miles, then a 224/224 .581/.581 for another 3k or so, and now the 238/240 .605/.609 for the last 2k .. Not quite 30k on mine, but enough miles to say the "test" period is over... I'm looking at changing the heads here once I squeeze the current setup to its fullest, to see just how much head technology has advanced since I got these back in 2000. Trending Topics
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