Power numbers
#21
Whistle Truck Guy
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Well I guess I'll spill the beans, just to see if what I think is wrong would cause this kind of power loss... At this point I'm not 100% sure it's off, but I'm 99%. When I put the cam in, I couldn't really see the timing gear on the crank, so I tried to put the new cam in in the same position I took the old cam out. Meaning I didn't line the crank and cam gears up dot to dot. I'm pretty sure I put it in at least 1 tooth retarded. It looked to be close to the same position, but it was off a bit. Didn't think it would make much difference. Ok, flame away. I put on my fire suit.
#23
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The last time I did a cam swap, I did it this way and it worked fine. Damn sure won't do it that way again... Been reading up on what happens if a cam is installed a tooth or two off, most if it was pretty much what's going on with my rig. The more I think about how the tune went and what the truck was doing, compared to what people have said happens when the cam timing is off, the more I think that is my problem. When the tuner started on the truck, before it went on the dyno, he had a hard time getting it to idle. Had to drill a fairly big hole in the throttle blade to get it to idle, even though the cam is pretty small, and the tps was showing the throttle to be open the maximum amount it could be open while at idle, or so the tuner said. I think it was around 28%. That seemed insane but I guess the nnbs trucks stay a little high on the throttle position at idle.
#24
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Not only did I do this when I had the small block chevy in my truck, but I installed the cam exactly 180* from where it should have been. Shitty night as you can image. So I basically did two cam swaps that day. And you have to pull the intakes off on the sbc stuff to get to the lifters/pushrods.
When I fired the truck up with the cam 180* out of position, it ran, but there was a loud clanking noise. Come to find out, one of the cam lobes was making contact with a crank weight . It didn't even leave a scratch on the cam, but the cam ground a nice chunk out of the crank....Can anybody beat that?
When I fired the truck up with the cam 180* out of position, it ran, but there was a loud clanking noise. Come to find out, one of the cam lobes was making contact with a crank weight . It didn't even leave a scratch on the cam, but the cam ground a nice chunk out of the crank....Can anybody beat that?
#27
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Not yet. Truck is still at the tranny shop without a converter. Sent it off to be restalled about 3 weeks ago and its still not back yet. Starting to get agitated.
#28
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Got the timing cover pulled off today. Sure enough, the cam was a tooth off. Got it squared up and replaced the On3 76mm with a Precision 7475. Gotta change the oil and then heading to the tuner Tuesday afternoon. Hopefully it makes a bit more power this time.