GM847 track times/dyno #s???
12-26-2008, 04:11 PM
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GM847 track times/dyno #s??? ok guys ive searched and searched for info on this cam and have come up with nothing really. i was wondering what everyone with this cam in a stock short block is running in the 1/4 and or dyno numbers. Everyone is pretty vague about it, most threads are its TO BIG dont run it itll destroy your bottom end spinning that much RPM. anyways any input would be great.
thanks
shawn
thanks
shawn
12-26-2008, 04:38 PM
#2
From the extensive searching I've done the people who actually have done it like it a lot.
Most times are in the 11.8-12.4 range cam only stock bottom end.
WHP is in the 350 range cam only stock bottom end.
ALL of the dyno graphs I've seen with the stock bottom end and heads have a hp peak at 5800-6000.
I've compared them to dyno graphs of other cams and the 847 may not be as flat, but it is STILL higher across the board vs any non custom cam.
Clearly a custom cam will be better in most cases.
http://web.camaross.com/forums/showt...light=847+dyno
Most times are in the 11.8-12.4 range cam only stock bottom end.
WHP is in the 350 range cam only stock bottom end.
ALL of the dyno graphs I've seen with the stock bottom end and heads have a hp peak at 5800-6000.
I've compared them to dyno graphs of other cams and the 847 may not be as flat, but it is STILL higher across the board vs any non custom cam.
Clearly a custom cam will be better in most cases.
http://web.camaross.com/forums/showt...light=847+dyno
12-26-2008, 04:42 PM
#4
Like you said, most threads that I have searched say that the GM847 is too large of a cam for a stock long block. I was going to get it, but after researching it, I opted for a CC503, I am happy with it, but I have no base of comparison against a GM847.
12-26-2008, 04:46 PM
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ok guys ive searched and searched for info on this cam and have come up with nothing really. i was wondering what everyone with this cam in a stock short block is running in the 1/4 and or dyno numbers. Everyone is pretty vague about it, most threads are its TO BIG dont run it itll destroy your bottom end spinning that much RPM. anyways any input would be great.
thanks
shawn
thanks
shawn
look up a board member KWIK96WS6 he ran that cam with ported heads and made like 400+ rwp i believe..
12-26-2008, 05:22 PM
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same here man like 2ft atleast
thanks for the input guys. so i can expect bottom 12s outta this cam before the heads get done? from what it looks like thats what everyone is running with it. Im shooting for 10s with ported heads and a 150 shot. think its possible?
thanks for the input guys. so i can expect bottom 12s outta this cam before the heads get done? from what it looks like thats what everyone is running with it. Im shooting for 10s with ported heads and a 150 shot. think its possible? 
12-26-2008, 05:41 PM
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your right ive found them and also seen that everyone who bashes the cam doesnt have any experience with and just say its a poor choice because thats what every other 847 hater says about it. ok sure you have to spin the hell out of it to make any power...i dont care ill spin 6700 out of it if it blows up so be it ill build another one.
12-26-2008, 06:15 PM
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Sounds like you already made up your mind before you asked for opinions. Theres better cams out there that can make the same hp at a lower rpm, but if you prefer the 847, go for it.
12-26-2008, 06:34 PM
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From the extensive searching I've done the people who actually have done it like it a lot.
Most times are in the 11.8-12.4 range cam only stock bottom end.
WHP is in the 350 range cam only stock bottom end.
ALL of the dyno graphs I've seen with the stock bottom end and heads have a hp peak at 5800-6000.
I've compared them to dyno graphs of other cams and the 847 may not be as flat, but it is STILL higher across the board vs any non custom cam.
Clearly a custom cam will be better in most cases.
http://web.camaross.com/forums/showt...light=847+dyno
Most times are in the 11.8-12.4 range cam only stock bottom end.
WHP is in the 350 range cam only stock bottom end.
ALL of the dyno graphs I've seen with the stock bottom end and heads have a hp peak at 5800-6000.
I've compared them to dyno graphs of other cams and the 847 may not be as flat, but it is STILL higher across the board vs any non custom cam.
Clearly a custom cam will be better in most cases.
http://web.camaross.com/forums/showt...light=847+dyno
12-26-2008, 07:38 PM
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i have the 292xfi cam which i belive its much bigger than the gm847 cam and i have no problem reving it up and getting all the pwer from it... its rpm range is from 2200 to 6200 and to top it off i have 1.6rr. i believe you will be fine with the gm847 cam.
12-26-2008, 07:42 PM
#16
I think the GM 847 cam is a great cam for the LT1. Especially in combination with set of ported heads and port matched intake. But then again, you can also get a custom grind close the to the same size as the 847 but with a tighter lsa. Just my opinion.
12-26-2008, 07:58 PM
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i pretty much have my mind made up im going to run the 847 with a set of hand ported heads and ported intake. hopefully itll go 11s on motor and 10s on bottle
12-27-2008, 09:31 AM
#20
I had the 847 in my old car and loved it. On a 383 with AFR210's it was good for 11.0's at 122+ mph.
But...
On stock or mild heads and stock or mild intake, it's no good. It tries to make power higher in the rpm range than the stock(ish) stuff can flow. If your goal is bottom 12's or even high 11's, you'd be better off with something smaller like the Crane 210/224.
But...
On stock or mild heads and stock or mild intake, it's no good. It tries to make power higher in the rpm range than the stock(ish) stuff can flow. If your goal is bottom 12's or even high 11's, you'd be better off with something smaller like the Crane 210/224.