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How bad are stock valveprings for D8OE heads ?

3433 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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D8 heads?
I wouldn't bother with them.
Sorry, but those are among the worst SBF heads ever made.
They make the E7s look good.
I know that is probably not what you were looking to hear, but...
You dont have to begin a new thread with every new question you have, you can continue on with related questions in the same one. It makes it tough for those trying to help you to keep abreast of whats going on. Don't be upset after only 1 hr that no one has replied, give people a chance.

Now, the first thoughts that come to mind regarding your question...

Those valve springs turned 30yrs old this year and have god knows how many heat cycles on them. Do you still think they perform to factory spec?

Something else to think about is that there are more factors than max lift to consider when selecting springs... One of them is the ramp rate. Aftermarket cams being more aggressive by nature are likely going to have steeper ramp rates which will also necessitate better springs. They are inexpensive and easy to swap ...not a gamble I'd make.

Im actually not familiar with that head and its flow rates etc, but by the looks of the post above mine, you need to go raid an explorer in a junk yard.
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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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You're way over thinking this I think. You're using E7's? Just call these guys Alex's Parts Sales tell them what you have and they'll sell you whatever you need.
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
What type of cam? Which cam? What are the spring requirements for your cam?
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?
To the OP - check out this thread - especially the last post.....
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?
Google the differences.

7's are fine for your combo, just need the matching retainer.

E7's have different valve tip lengths. Most kits specific for e7, gt40 and gt40p will have specific locks for the intake and exhaust to make up most of that difference then you will have verify installed height.

If your spring specs to 1.700 and you are higher you will shim. If you are lower you will have to play with different locks or retainer or combo of locks retainers and shims.

The easy and least expensive kit I know of for lower spring pressures is Alex's spring kit. Call him and ask him what he has for you.
Yeah the installed height on the new ones is 1.700
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