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How bad are stock valveprings for D8OE heads ?

3440 Views 14 Replies 6 Participants Last post by  83gtfox
With my new cam, I was wondering if I could use the stock D80E springs or if I needed to get slightly stiffer ones. The lift is only about .040 higher on the intake and .012 higher on the exhaust, so I figured it would be ok. If I did actually need new springs, what are some you guys recommend? Ny stock ones were about 1.695 in tall (installed) had an O.D. of 1.430, and had an I.D. of about 1.030. I really don't want to machine down the spring pocket, especially because I'll be pouring money into crap D80E heads, or slightly better but still cheap E7 heads. (I know, I know, GT40 is the way to go, I'm just on a tight budget right now.) It's a lot to get, but if you guys could help a brother out it would be great!
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The car has just under 50,000 miles on it and doesn't have any track or major strip time. It's been a daily driver (fair weather of course) but hasn't seen any abuse. I actually decided to ditch the D8 heads and I bought some better E7's, but the springs in the D8's are very good. I personally believe they are good enough to handle the factory cam. I was thinking that I could swap those springs into the E7's and use them with the new cam. I was just wondering if they could even possibly handle the new cam in the condition that they're in. I can't seem to find good springs that would have appropriate pressure for the break in. I was about to get Comp's 942-16 springs, but they aren't a double spring design and the open pressure on them is 284. I've heard anything over 250 is too strong for break in, and you either need to remove one of the springs in a double spring design or get low ratio rockers. I don't want to grind down the lobes, so if the stock springs can possibly handle the new cam, I will use them because their pressures are good for break in. I know, it's complicated, but I'm just confused about what the best option is.
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Yeah, I'm on a bit of a budget, and I know that they will easily make 30-40 hp over D8 heads. With new components and a little polishing, they're just what I need. As far as springs go, I'm just gonna go with the ones recommended for the cam. I just realized after days of thought that I could just use the stock springs for break in and put the new ones in afterward. Wow. Such a simple solution for a seemingly impossible problem.
What degree retainers and locks should I go with though? There is no recommendation as far as 7 or 10 degree. Keep in mind I'm getting Comp Springs PN 942-16
The cam I'm using is comp's 31-218-2. It has .456/.456 lift, 218/218 duration at .050, and 110 LSA. The springs recommended for my cam on Summit were Comp's 942-16. I have no tangible spring requirements, but for my application these springs seem ok. As for break in, I'm putting on the stock springs wich have lower pressures. (So I din't grind down any lobes.) What are some differences between 10° and 7° locks and retainers? Which do you reccomend?
The springs I'm looking at have a seat pressure of 115 lbs and an open pressure of 284, which seems perfect. For break-in I'll keep the stock springs on and pull them with this little spring puller from Harbor Freight after break-in is done. The recommended retainers for these springs are 10 degree, which I understand to be better. Any opinions on 10 degree vs 7 degree? Pros and cons of both?
Yeah the installed height on the new ones is 1.700
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