Sowing machine/diesel sound??
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I will post an update as soon as i find out what the proper pr lenght i need, if it is that.
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ive had this sound before and after i did my hotcam swap. i reused my stock PRs.
im interested to see how your PR length checks out.
i need to go back and check my base circle, but i remember the base circle on the hotcam wasnt as small as what people said aftermarket cams usually are...
how is the PR checking tool work?
jeremy
im interested to see how your PR length checks out.
i need to go back and check my base circle, but i remember the base circle on the hotcam wasnt as small as what people said aftermarket cams usually are...
how is the PR checking tool work?
jeremy
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did you by chance put in dual valve springs? Because when i did my head and cam setup i chose dual valve springs just to be safe but when you do that these ls engine tend to have a sewing machine sound. I dont mind it since i know what it is. Ive been running my car like this for over 2 years with 0 problems and many low 11 second passes.
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I have dual springs, I have checked my PR length several times and the dam thing is still pretty loud. I think I'll just run it like itsok and if something goes out it goes out.
did you by chance put in dual valve springs? Because when i did my head and cam setup i chose dual valve springs just to be safe but when you do that these ls engine tend to have a sewing machine sound. I dont mind it since i know what it is. Ive been running my car like this for over 2 years with 0 problems and many low 11 second passes.
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did you by chance put in dual valve springs? Because when i did my head and cam setup i chose dual valve springs just to be safe but when you do that these ls engine tend to have a sewing machine sound. I dont mind it since i know what it is. Ive been running my car like this for over 2 years with 0 problems and many low 11 second passes.
I went to TXMaro's shop today and had a chance to listen to his car. They sound almost identical. So it's more than likely a combination of the forged bottom end and the pr slack.
Still waiting on the pr checker.
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well i took a quick vid of my car. i think its just a normal sound, but its very annoying when i hear it in a drive through or stopped next to a wall.
the ticking is more obvious from the wheel well area...
http://www.youtube.com/watch?v=58cJhwpfsoI
as for the pushrod length, ive done some investigating. i pulled all the PRs and they are all perfectly straight. i measured my stock cam's base circle. the weird thing is that if i remember correctly, the hotcam had a 1.520" base circle, while the stock LS6 cam measures 1.495". everything ive read states that the aftermarket cams have smaller base circle. i dont know who makes the hotcam for GM, or if they actually make them. i thought comp made the LT4 hotcam, not sure though.
so, if the base circle is larger, id need shorter PRs right?
now, ive read comp's info on the PR lenght checker. its kinda hard to tell if ive got good geometry or not because there isnt a precise point of contact like a roller rocker has, but the geometry looks pretty good to me with the stock PRs. what do you guys think???
dont mean to highjack the thread, but its i figure we could make this a group thing....
Jeremy
the ticking is more obvious from the wheel well area...
http://www.youtube.com/watch?v=58cJhwpfsoI
as for the pushrod length, ive done some investigating. i pulled all the PRs and they are all perfectly straight. i measured my stock cam's base circle. the weird thing is that if i remember correctly, the hotcam had a 1.520" base circle, while the stock LS6 cam measures 1.495". everything ive read states that the aftermarket cams have smaller base circle. i dont know who makes the hotcam for GM, or if they actually make them. i thought comp made the LT4 hotcam, not sure though.
so, if the base circle is larger, id need shorter PRs right?
now, ive read comp's info on the PR lenght checker. its kinda hard to tell if ive got good geometry or not because there isnt a precise point of contact like a roller rocker has, but the geometry looks pretty good to me with the stock PRs. what do you guys think???
dont mean to highjack the thread, but its i figure we could make this a group thing....
Jeremy
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yeah, definitely different sounds. i think mine is probably normal but it bugs the crap outta me!
i'll know for sure when i replace or have my heads ported. ill throw some LS7 lifters in while im in there and see how she sounds after that. it will be a while till i do that...
i'll know for sure when i replace or have my heads ported. ill throw some LS7 lifters in while im in there and see how she sounds after that. it will be a while till i do that...
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I called TSP when i bought my cam and asked them the same question that everyone is wondering here. With my stock 243 (practically the same as ls1 241's) heads on a ls1 block with stock lifters and rockers ...... I asked what pushrod i should use. Since this is the typical setup for most cam buyers i figured they would know which PR to use in terms of length. They told me to go with the 7.4 hardened. Thats what i am doing this weekend. All this about checking with a checker..... sure might be the absolute way to get the measurement but i am sure that TSP knows what they are talking about. I have heard from many people that after installing a cam that you will get the sewing machine sounds and whatnot and a overall noisier valve train. I am expecting that. I can rest assured that TSP has done their research on the PR length and that they know what they are talking about. I would call them and chat with them about your specific setup and if they are not sure i bet they will suggest the checker. Until then i am going with what they recommend. I have faith that they have done this before and know what they are talking about.
Is the PR length checker the absolute way to know for sure .... yes absolutely however i trust their advise since this is what they do. Like i said if they questioned it .... so should you. If not i have faith that they know what they are doing.
Is the PR length checker the absolute way to know for sure .... yes absolutely however i trust their advise since this is what they do. Like i said if they questioned it .... so should you. If not i have faith that they know what they are doing.