couple of questions about gm847 cam
11-30-2005, 02:07 PM
#1
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couple of questions about gm847 cam would i need new pushrods and lifter upgrading to this cam? also if anyone knows the powerband of the cam...right now my shifts are set at 6200, would i need more rpm is basically what i'm asking. Thanks
11-30-2005, 02:50 PM
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the only reason you would need new pushrods would be putting in roller rockers that require guide plates, which would rwquire you to install hardened pushrods.
11-30-2005, 04:10 PM
#4
Originally Posted by DarkDemon
would i need new pushrods and lifter upgrading to this cam? also if anyone knows the powerband of the cam...right now my shifts are set at 6200, would i need more rpm is basically what i'm asking. Thanks
11-30-2005, 04:12 PM
#5
Originally Posted by BigKap94z
Yes, you need to really twist the 306 and GM847 to benefit from the upgrade. I would say at least 6500 RPM, most likely a tad higher. Shifting before that will be before the cam even peaks...and if shifting at 6200 your times will not be faster than your current camshaft most likely. I have read multiple reports from people that swapped to a much larger cam, and there ET's were .2-.3 slower than before when shifting between 6k-6,300.
I run mine to 6200 right now, but am gonna bump it up more
11-30-2005, 05:44 PM
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i shift mine somewhere near 6700-6800 in my 383 6spd car
if i remember peak hit around 6350'sh but didnt rapidly drop off either in my combo
but dont know what VS's you have allready on the 305 cam...
if i remember peak hit around 6350'sh but didnt rapidly drop off either in my combo
but dont know what VS's you have allready on the 305 cam...
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11-30-2005, 06:18 PM
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yeah well right now car seems to run out of steam at like 5500 or so...figured more cam to match the heads flow think i'll have the shifts moved to 6500 and see how that goes
11-30-2005, 09:13 PM
#11
Crane makes a cam with the exact specs, I have heard some of the GM performance cams are made by Crane, which would make sense I guess.
234/242 .539/.558 on a 1.5 rocker 1.6 makes it around 575/595 I think. Max rpm 6800 Valve float 7200. Love mine great lope, good power even with the shitty stock heads. Gotta spin it high though.
http://www.cranecams.com/?show=brows...tType=camshaft
234/242 .539/.558 on a 1.5 rocker 1.6 makes it around 575/595 I think. Max rpm 6800 Valve float 7200. Love mine great lope, good power even with the shitty stock heads. Gotta spin it high though.
http://www.cranecams.com/?show=brows...tType=camshaft
Last edited by slowmofo; 11-30-2005 at 09:33 PM.
11-30-2005, 10:23 PM
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I'm looking into a similar cam to the 847, a grind made by Cam Motion. They recommend using a comp 977 (not 987, it's too weak).
The only thing I'm worried is that this is too much cam for stock cubes. It seems like there are two kinds of cars running it:
1) Unported stock heads with bolt-ons
2) Stroker motors
Anybody running this cam with ported heads and a stock bottom end?
The only thing I'm worried is that this is too much cam for stock cubes. It seems like there are two kinds of cars running it:
1) Unported stock heads with bolt-ons
2) Stroker motors
Anybody running this cam with ported heads and a stock bottom end?
12-01-2005, 12:34 AM
#13
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Originally Posted by Z284thgen
VS= Valve Springs
said they should be good for most any cam i wanna slap in
12-01-2005, 01:14 AM
#14
I ran mine to 7,000 shifts on a stock short block with stock lifters and push rod(95 had hardened push rods). after the first season when I pulled the push rods 10 were bent. Kept the stock lifters with new push rods and went two more seasons.
Car only ran 11.8s though
Car only ran 11.8s though
12-01-2005, 04:10 PM
#16
Originally Posted by TwoFast4Lv
I ran mine to 7,000 shifts on a stock short block with stock lifters and push rod(95 had hardened push rods). after the first season when I pulled the push rods 10 were bent. Kept the stock lifters with new push rods and went two more seasons.
Car only ran 11.8s though
Car only ran 11.8s though
11.80's is slow
12-01-2005, 04:43 PM
#18
crane spring and retainer kit pt#10308-1
Includes Valve Springs Part No. 99893-16
Retainers Part No. 99951-16
Locks Part No. 99097-1
Shims Part No. 99050-1
stock 94 hardened pushrods, stock lifters, stock 1.5 rockers with some 1.6's one the way.
Heads are stock with some porting and gasket matched. Waiting for tax return to get some heads.
Includes Valve Springs Part No. 99893-16
Retainers Part No. 99951-16
Locks Part No. 99097-1
Shims Part No. 99050-1
stock 94 hardened pushrods, stock lifters, stock 1.5 rockers with some 1.6's one the way.
Heads are stock with some porting and gasket matched. Waiting for tax return to get some heads.
