Sowing machine/diesel sound??
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I have just intalled a ms3 and Afr 205's on top of a lunati 383 stroker kit with -8cc wiseco pistons. The car sounds like a diesel/ sowing machine. Its faint but i can hear it like 10-15 feet away from the car. Is this piston slap from that piston or what?
Is anyone running these pistons with similar probs??
Is anyone running these pistons with similar probs??
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If it is piston slap you should have heard it before the H/C install. And only at start up...
The quicker lift cam lobes of your cam + high pressure springs are noisier than stock so that is prolly your issue...
Did you check your PR length with a checker......If not do so.....
The quicker lift cam lobes of your cam + high pressure springs are noisier than stock so that is prolly your issue...
Did you check your PR length with a checker......If not do so.....
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I havent checked the pushrods yet because everyone using the ms3 is runnign 7.4's thats exactly what i put in with stock head gaskets. All the lifters are brand new ls7's.
It did have the knock before the cam swap. And its louder when cold, but gets slightly quieter when hot. But it is still there all the time.
It did have the knock before the cam swap. And its louder when cold, but gets slightly quieter when hot. But it is still there all the time.
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I havent checked the pushrods yet because everyone using the ms3 is runnign 7.4's thats exactly what i put in with stock head gaskets. All the lifters are brand new ls7's.
It did have the knock before the cam swap. And its louder when cold, but gets slightly quieter when hot. But it is still there all the time.
It did have the knock before the cam swap. And its louder when cold, but gets slightly quieter when hot. But it is still there all the time.
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how long have u ran ur car like this? i recently pulled my whole motor and checked bearing tollerances beacause i thought it was a rod bearing. everything checked out ok. changed the cam bearings and put all new valve train. my only other guess is piston slap.
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It may be a combination if incorrect pushrod length and piston slap. The cylinder head change also has an effect on pushrod length. I would get a pushrod length checker to make sure.
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I ask because a few people I have asked about my engine sounding weird say a forged LS1 will kinda sound like a diesel engine. I just built mine and thought "dam, this engine sounds bad, I totally fucked up". Started asking around and most everyone tells me the sound is normal, for forged that is. I wonder if anyone else with the diesel sound is forged.
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Took it to about 4 mechanics, 2 said lifters, 1 said pushrods, and 1 said rockers (but he didn't really look into it).
After that I knew it wasn't piston slap.
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you need longer pushrods. You don't have enough preload on the lifters. Larger cams have smaller base circles thus reducing the preload on the lifter. Everybody told me to use 7.4 also but everybody also had alot of noise. They say it's normal but it's not. Get a pushrod checker and you will see that you don't have much preload at all. Mine needed a 7.440 so I had to go with 7.425 so I wouldn't go ver the preload limit. Some say I could run the 7.450 but I would rather be just a little under preload than over.
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Idk, like 6 months, maybe? I didn't really care at first, but it started to get colder and it got louder, so then I thought, wow, this might actually be bad.
Took it to about 4 mechanics, 2 said lifters, 1 said pushrods, and 1 said rockers (but he didn't really look into it).
After that I knew it wasn't piston slap.
Took it to about 4 mechanics, 2 said lifters, 1 said pushrods, and 1 said rockers (but he didn't really look into it).
After that I knew it wasn't piston slap.
I'm going ot go compare it to TxMaro and see what the difference is..
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you need longer pushrods. You don't have enough preload on the lifters. Larger cams have smaller base circles thus reducing the preload on the lifter. Everybody told me to use 7.4 also but everybody also had alot of noise. They say it's normal but it's not. Get a pushrod checker and you will see that you don't have much preload at all. Mine needed a 7.440 so I had to go with 7.425 so I wouldn't go ver the preload limit. Some say I could run the 7.450 but I would rather be just a little under preload than over.
I had a MTI X1 cam and those were the pr's they were using on that cam, and it still made the same noise?