New cam
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Instructor
Joined: Aug 2014
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New cam
I have converted my 350 to carb and now I want to put in a new cam.. I'm looking at one that has a 450/450 lift with 1.5 rockers 274 advertised duration 106 lobe separation and 104 intake centerline.. Question is can I use this with stock springs? I have heard that 480 lift is max for stock springs... And shouldn't this cam have a rough idle? Thanks
Thread Starter
Instructor
Joined: Aug 2014
Posts: 249
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It's a elgin e1785p. Says the power band is 1800-5200 rpm.. Stock converter can be used. I really want the Lopey idle.. It's not a race car tho. Didn't want to have to change springs that's why I was looking for a lower lift cam. I really can't remember but I think in the past I have used a 488 lift with stock springs and didn't have a problem.. I always change lifters with the cam though.
Drifting
Joined: Mar 2006
Posts: 1,263
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From: Wabasha Mn
Cam is copy of the old crane 274H06 lift rules cam with 218-218 dur af 050. I had this cam in my carbed 84 c4 and used my stock springs with 70 k on them with no problems. If you have an automatic this cam does not like to idle below 600 rpm in gear. You could uses your stock springs for cam break in and then change if needed. Cam has a nasty idle with the 106 lsa but with the short duration is pretty streetable in a low c.r. 350. I later changed to summit/dart 152123 large valve heads and went with an isky solid lifter cam.
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From: altered state
St. Jude Donor '05
600 would work just fine
Def spend $40-50 on a spring kit
When I was young I ran a .480 type cam on a stock spring. "seemed fine" but looking back it was floating valves and wasnt even aware of it. Can happen long before you hear it. Break in with the old springs not a bad idea at all
A pack of decent seals is no more than $20 do them while you swap springs. Check for coil bind too. .055 is good and safe;make sure nothing is contacting the guide/seal when you turn the motor over by hand (you should be able to see it)
Def spend $40-50 on a spring kit
When I was young I ran a .480 type cam on a stock spring. "seemed fine" but looking back it was floating valves and wasnt even aware of it. Can happen long before you hear it. Break in with the old springs not a bad idea at all
A pack of decent seals is no more than $20 do them while you swap springs. Check for coil bind too. .055 is good and safe;make sure nothing is contacting the guide/seal when you turn the motor over by hand (you should be able to see it)
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From: altered state
St. Jude Donor '05
Try the Z/28 spring.They should be checked anyway
lift is one thing but your cam probablyis a little more aggressive than an oem on the acceleration rate of the cam. This way you dont run into valve float.Pioneer sells a kit for cheap
lift is one thing but your cam probablyis a little more aggressive than an oem on the acceleration rate of the cam. This way you dont run into valve float.Pioneer sells a kit for cheap
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Instructor
Joined: Aug 2014
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Is it possible that with them I wouldn't have to shim them and get away with my original retainers? A guy at a machine shop here has some Z28 springs I think their elgin brand would they be the same? Or where can I find pioneer Z28 springs?
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