Any one running kelford 272 on stock head
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From: was Georgia, now williamsport PA
There are a myriad of ppl on the stock valve train. Will the stocks springs wear? Yes. Will aftermarket springs wear? yes.
Should they be replaced? Hell yes.
The cams are aggressive. The stock v-train likely has difficulties keeping up with the closing ramp of the cams but not bad enough for valve contact. Still a loss.
I put VIIIrs' car together. He had a much lesser set up at the time, and Im sure he will be upgrading soon.
Should they be replaced? Hell yes.
The cams are aggressive. The stock v-train likely has difficulties keeping up with the closing ramp of the cams but not bad enough for valve contact. Still a loss.
I put VIIIrs' car together. He had a much lesser set up at the time, and Im sure he will be upgrading soon.
There are a few shops that charge $800 to install them by removing the head and replacing headgasket also.
If you miss a shift and put it in the wrong gear it does not matter if you have springs and retainers or not. When the motor revs to 11,000 rpms it all becomes a mess just the same. I am actually seen people do this.
That is not true. While you might discount it to "speculators" this is part of any internet myth started by Cosworth. The fact of the matter is cams with more lift and larger duration take their toll on stock springs at ALL rpms and not just at redline when the 5th order harmonics start to play into it. Anything past an S1 or HKS 272 for lift and duration at .040/.050 (not advertised) will begin to shorten the valvesprings lifespan. I believe they are 214-218* at .040 for the cited examples.
I might not have them in my car, but it doesnt mean I havent tuned them, built motors or installed them. Its not a matter of valve contact from the valve float. Its decreased valve control over time, sagging (loss of pressure), and then ultimately broken valvesprings. Anything run to within 3-4% of the rpm a known valvefloat point is still doing damage whether its seen or not.
aaron
I might not have them in my car, but it doesnt mean I havent tuned them, built motors or installed them. Its not a matter of valve contact from the valve float. Its decreased valve control over time, sagging (loss of pressure), and then ultimately broken valvesprings. Anything run to within 3-4% of the rpm a known valvefloat point is still doing damage whether its seen or not.
aaron
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