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PRC 650 Valve Spring Check

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Old Feb 24, 2017 | 03:49 PM
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Default PRC 650 Valve Spring Check

Anyone measured a PRC 650 spring back when it was new?

Unfortunately I did not.

I called Texas Speed and was very surprised at the lack of info the rep could provide. All he would say is that he has had them on his car w/nitrous and many drag strip passes and they're great, so I should be ok. I asked how he knows they're still good and he didn't have an answer. I asked what they were rated for and he wouldn't say (said he didn't know) and wouldn't give any guidance on how much of a deviance would still be considered acceptable. Said he would consult their engine builders and get back to me. He never called me back. I tried emailing Jason (listed as co-owner) through another forum and got zero response from him as well. They've just gone from the top of my list for aftermarket parts to the bottom!

An internet search turned identified the pressures as:

145 lbs at 1.8"
450 lbs at 1.15"


Today I measured eight of my springs on an MTS UTM (waaaaay overkill for just measuring a spring):
- Spring free length only varied by 0.02"
- 1.80" length = 147 to 152 lbs (looks good)
- 1.15" length = 418 to 422 lbs (maybe a problem)

So, is the low pressure at 1.15" an indication of a problem with the springs or just that PRC had overstated the pressure?

If you happened to measure them before installing, let me know what you got!

Thanks
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