What makes a ground thumper?
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
What makes a ground thumper?
Have you ever been around a car, that just shook the ground when it ran? I mean thumping! What does this come from? I want to build another motor that really pounds the earth.
High compression?
Not much cam overlap?
High compression?
Not much cam overlap?
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Re: What makes a ground thumper?
Loads of displacement.
Wayyyy too much overlap. Particularly on the exhaust side.
Oversized exhaust, usually a fiberglass packing style exhaust (cherry bombs), or no muffler at all. That'll do it alright.
Wayyyy too much overlap. Particularly on the exhaust side.
Oversized exhaust, usually a fiberglass packing style exhaust (cherry bombs), or no muffler at all. That'll do it alright.
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: What makes a ground thumper?
Im working on a 350 for an s10. I know, I know. Probably going to run E85 so I'm going to bump up the cr to like 12-13:1. The truck is going to be fast no matter what, so I want it to sound ghoulish.
So a lot of overlap? Like 106? Does this mean the exhaust opens early and lets some extra cylinder pressure out the exhaust?
My car has 110 lsa and I was breaking it in open headers. Sounded great, but didnt have a noticeable thump to it. 9:1 cr though.
So a lot of overlap? Like 106? Does this mean the exhaust opens early and lets some extra cylinder pressure out the exhaust?
My car has 110 lsa and I was breaking it in open headers. Sounded great, but didnt have a noticeable thump to it. 9:1 cr though.
#4
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Re: What makes a ground thumper?
240+ duration, high compression, long tubes, h-pipe, loud mufflers, the 106lsa does help the idle note a bit as well, big displacement, etc etc. I don't think my exhaust is that much of a thumper, but here's a little video of it, you can hear it at idle halfway through.
http://myspacetv.com/index.cfm?fusea...ideoid=9635776
http://myspacetv.com/index.cfm?fusea...ideoid=9635776
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Car: 82 Berlinetta/57 Bel Air
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Re: What makes a ground thumper?
The family shih tzu when scratching an itch behind its ear. Really loud thumping sound on the wood floor.
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: What makes a ground thumper?
I hate those dogs. Shittyzu owners get real offended when I say that too. Well xp3, you pretty much just explained my car, and it sounds an a lot like yours. I love the sound but I want something that sounds different. It could be that I'll only get it from a big block. That explosive tightly wound nastiness. When you start it the earth shakes. I've heard it on cars before, but didnt know exactly what was under the hood, nothing crazy. Similar to the sound of a top fuel car. But not quite...........my car shakes houses but its a high frequency. I want a shaky low frequency, that may only come with some real big displacement. 450ci+. Maybe I'll start looking for a big block?
But I sure as hell aint putting it in the s10.....
But I sure as hell aint putting it in the s10.....
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Car: 1988 Trans Am GTA
Engine: 350 4BBL
Transmission: 700R4
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Re: What makes a ground thumper?
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#8
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Re: What makes a ground thumper?
Yea, when I said overlap I meant cam duration-wise, but yea, LSA does it too.
I know xp3ndbl3 has a big cam, but what is the LSA on it?
If you run a 106LSA it'll RUMBLE. A lot of it is in the exhaust too. *Turn downs*, true duals, x-pipe, loud muffler etc.
I know xp3ndbl3 has a big cam, but what is the LSA on it?
If you run a 106LSA it'll RUMBLE. A lot of it is in the exhaust too. *Turn downs*, true duals, x-pipe, loud muffler etc.
#9
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Re: What makes a ground thumper?
I agree that a nasty big block motor is probably the easiest way to get that ground pounding sound. When I used to work as a mechanic, my old boss there had a 72 Camaro that he put a 454, punched out to a 468 in. It had a Weiand Team G intake, square port alumimum heads, some nasty cam, and a Holley Dominator carb on it. I think the exhaust really helped too. Hooker Super Comp headers with 4" pipes and glasspacks. You could totally feel every exhaust pulse in the pavement when you were standing next to it. One of these days I'll get around to building the 454 I've got sitting in my storage shed, and get it dropped in the 66 Chevelle I bought several years ago. It's just hibernating in the field for now since my thirdgen seems to be a bottomless money pit!
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Car: 1988 SC Convertible
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Axle/Gears: 3.23 posi w/PBR's
Re: What makes a ground thumper?
The 79 T/A I traded for my 91 had an Olds 350R (oiginally an Olds 403 car) with a huge cam, full length hooker headers, true duals to two 40 series flomasters and turndowns right before the rear axle. Even just at idle in the driveway it shook pictures on the wall in my house. I don't know the specs on the motor since it was in the car when I bought it, but it was a hell of a pavement pounder. I regret trading it off sometimes, but when it's 90-100 degrees outside I don't miss it at all when I turn on the A/C of my third gen.
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Car: 1991 Camaro RS
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Re: What makes a ground thumper?
Best bet is tons of cam, full length headers, at least 3in pipes with turn downs(as little pipe after the mufflers if you have em get that noise level up nicely). Also a way too big carb, single plane manifold, and i'd say flowmaster super 40's they are retarded loud
#12
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Re: What makes a ground thumper?
[retarded loud[/QUOTE] Hey FYRCHKN, that 79 T/A you had reminds me of the 76 T/A another buddy of mine had. He had a stout 455 in it with a Super T10. It had Super Comp headers, and 4" duals that dumped in front of the rear axle. That car pounded the ground too.
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Car: 1984 Trans Am
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Re: What makes a ground thumper?
basically my combo.. 385, 10.65:1, 110LSA, 260/260 duration @ .050, 306/306 advertised, .592/.555 lift, solid tappet cam, long tubes, true duals with some excuse for a muffler.. its alright, doesnt "shake" the ground.. just kinda makes it vibrate a little..
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Car: 92 GTA/ 00 TA
Engine: 383/350
Transmission: 700R4/T-56
Re: What makes a ground thumper?
Mine vibrates the toilet in the house. 224/230 and 112 lsa. 3" true duals, h-pipe, 30" chambered mufflers, exhausting out the rear.
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Re: What makes a ground thumper?
I think so. They also won't burn out like glasspacks.
Standing anywhere around the car is loud. Sounds mean. The rough idle with a bit of lope sounds good. Once I step on the gas.....wow does it get loud. It sounds like i'm running open headers.
My friend was able to hear the car from 1/2 mile away. It would've been farther but I had to get off the gas.
I'm still trying to get a sound clip. As of yet I have nothing that'll record it.
Standing anywhere around the car is loud. Sounds mean. The rough idle with a bit of lope sounds good. Once I step on the gas.....wow does it get loud. It sounds like i'm running open headers.
My friend was able to hear the car from 1/2 mile away. It would've been farther but I had to get off the gas.
I'm still trying to get a sound clip. As of yet I have nothing that'll record it.
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Car: 1991 Camaro RS
Engine: 357cid
Transmission: T5 Swap
Axle/Gears: 10bolt 7.5" 3.23 soon to be 3.73
Re: What makes a ground thumper?
I think so. They also won't burn out like glasspacks.
Standing anywhere around the car is loud. Sounds mean. The rough idle with a bit of lope sounds good. Once I step on the gas.....wow does it get loud. It sounds like i'm running open headers.
My friend was able to hear the car from 1/2 mile away. It would've been farther but I had to get off the gas.
I'm still trying to get a sound clip. As of yet I have nothing that'll record it.
Standing anywhere around the car is loud. Sounds mean. The rough idle with a bit of lope sounds good. Once I step on the gas.....wow does it get loud. It sounds like i'm running open headers.
My friend was able to hear the car from 1/2 mile away. It would've been farther but I had to get off the gas.
I'm still trying to get a sound clip. As of yet I have nothing that'll record it.
#18
Re: What makes a ground thumper?
I hate those dogs. Shittyzu owners get real offended when I say that too
but yes, high compression and inches with a big cam and abit of overlap helps ruin the earth lol Baddest car i've heard was a open header Yenko or Motion 427 big block in a old 69 (i think) camaro. car was a monster. something like 13 to 1 compression, the works. Car started up and literally shook teh ground from far away. Just intimidating. I've heard 7 -8 second drag cars sound tammer than this car
#19
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: What makes a ground thumper?
Awesome, thats what I want. I guess I'll start building one. Don't know much of anything about big blocks, spent the last three years getting to know everything about small blocks. Have to get this car done first though...
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