Join Date: Mar 2003
Location: Spokane WA
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Re: GM 3100 V.S. retainers Why? what an I missing
depends on the mods. If you are running a ported head and plenum and even more cam you should run the Comp beehives. Even big cams have no issue with them. Then there is how long you expect to run the same engine or if you want to run a on a track at high RPM for long periods. The beehives are best, whether or not you need them often isn't true. I ran the 3.3s first because I rev the engines up higher than normal, with porting they like 6,500 RPM. With a cam and a plenum they like 7,500 RPM. At that point you can use the beehives. If your staying under 5,000 for the most part then they aren't worth it.
I think if I was doing something stock I'd just run the MP 813 springs with dampener, a stock turbo spring basically with a dampener. Then with some porting and maybe more turbo but staying with a stock cam I'd run the 3.3s. That way your not dealing with springs that break down with mileage and higher RPM. Go farther with a plenum and a cam and your now really revving up past 6500 RPM then look at the Comps. If you run near stock but 30-40 PSI of boost, which people do, then the Comps will help too.
For most though the 3.3 and the PT setup reduces a ton of valve train stress over stock. Gaps from squishing lifters causes pounding, vs a PT that keeps the follower on the cam. Then the conical 3.3 spring really reduces weight removing stress off the cam lobes, followers and even the timing belt.
Some are happy with the crane non conical spring from FWD, but the spring rates on that cam are as low or lower than turbo stock springs. So they are either listed wrong or they are a good stock replacement.
The comp Beehive conical spring has the S60 MP spring rates, seat and open. But weigh a lot less and work so far above 7,000 RPM on a .550" lift cam. Making the Comp Beehive possibly the last spring ever needed for the 8v, until something new happens like a custom race head like an Indy head is made.
So many are running the Comp Beehives with a stock cam and just don't upgrade. Some save a few $ and do 3.3 springs, not needing that much. You add a spring normally to match a cam, with old springs. But even with V8s the Beehives are treated as a one size fits all spring, within reason lol. When looking at springs you match them to a small range in cam lift and RPM. So every jump in cam you change the springs, the Beehives are listed up to a lift. The Comps are up to .600" lift, not a .550"-.600" lift spring for instance. So how they are recommended is different.
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