Valve stem seals crushed, LS7. More spring?

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mdrew
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Re: Valve stem seals crushed, LS7. More spring?

Post by mdrew » Thu Feb 09, 2017 9:06 am

Kinda.... Finding a good spring for this engine that will fit the spring pockets, with wire that's made in the USA, and getting the loads I want is proving to be more challenging than I thought it would... What makes this difficult, and also unusual, is most who use these rockers on this engine, are not using a hydraulic roller. They're "all in" with a solid roller set up, and lifts are .700+.

I've gotten differing opinions on just how much seat load to target. Open load recommendations are pretty consistent at 450-500, and seeing how I didn't have float before at 470 - I figure that's a good target.

Geoff Skinner tells me 140 - 150 seat, 400+ open.

PAC suggests a minimum of 160 seat load, but to stay under 180.

Martin Smallwood tells me ~180 seat, and 450+ open. Martin has used these rockers on this engine before, several times. I'm inclined to lean toward his suggested loads, seeing how he's got real world experience with similar LS7 builds.

The Ferrea LS spring (that PAC makes for them) rate/loads look great, but they are simply way too proud for those springs. Ain't spending $900 for a set of springs and Ti retainers. At 0.080 coil bind distance, seat load would be 160/173 and 470. At 0.060 CB dist; loads are 169/183 / 480.

I'll most likely just get a set of PAC 1207X's coming and set them up 0.080" from coil bind. Unless my math is off, that's 176/189 seat load, and 466 open.

Newold1
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Re: Valve stem seals crushed, LS7. More spring?

Post by Newold1 » Thu Feb 09, 2017 10:21 am

Did you check with the valve spring guys at Eibach?

mdrew
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Re: Valve stem seals crushed, LS7. More spring?

Post by mdrew » Thu Feb 09, 2017 11:36 am

Newold1 wrote:Did you check with the valve spring guys at Eibach?
They make valve springs?

Newold1
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Re: Valve stem seals crushed, LS7. More spring?

Post by Newold1 » Thu Feb 09, 2017 11:39 am

Yes sir they do and they make some pretty darn good ones. Go to their website and click on valve springs. It will be a bit of an eye opening experience. :wink:

mdrew
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Re: Valve stem seals crushed, LS7. More spring?

Post by mdrew » Thu Feb 09, 2017 12:26 pm

Well I'llbedamned...... Learn something new every day.

Not much for the chevy LS platform, unfortunately. At least not in their catalog.

Newold1
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Re: Valve stem seals crushed, LS7. More spring?

Post by Newold1 » Thu Feb 09, 2017 3:21 pm

Call and talk to one of their valve spring guys. with all the fast movements in LS engines they may have some new offerings not even in the catalogue or on website yet.

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