bump stops
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From: Southern Middle Tennessee
Car: 1986 Black IROC
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bump stops
I've read lots about cutting bump stops but don't know what they are, where they are and what it does to cut them and how to cut them...
Can anybody give me this information?
Thanks
Can anybody give me this information?
Thanks
Supreme Member
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From: Orlando
Car: 1991 Camaro Z28
Engine: 357, Canfield heads, solid roller,
Transmission: Upgraded 03 Cobra T56
Axle/Gears: 9" 3.50 gears and Detroit Locker
Re: bump stops
No reason to cut them since you can just unbolt them. Can't think of a reason to do that though either. Some people may take them off of they lower the car, bit then bottoming out is going to be loud and jolting with nothing soft to dampen it. I would leave them alone.
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
Only reason you should be cutting the bump stop area out is to gain clearance for wider rims. I did a write up a while ago with pics. Just do a search for 15x10 rims with 6.5 backspacing.
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From: Orlando
Car: 1991 Camaro Z28
Engine: 357, Canfield heads, solid roller,
Transmission: Upgraded 03 Cobra T56
Axle/Gears: 9" 3.50 gears and Detroit Locker
Re: bump stops
True. Forgot about stuffing big wheels. But this involves cutting more than just the bump stop as well.
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From: Rochester NY
Car: 1984 z28
Engine: 355
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Axle/Gears: Moser 9" 4.11
Re: bump stops
This is what I had to do to put in a 15x10 6.5 BS rim with a 275/60/15 tire.
https://www.thirdgen.org/forums/whee...get-15x10.html
https://www.thirdgen.org/forums/whee...get-15x10.html
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Re: bump stops
Of course you need to cut the bumpstops if the car is lower otherwise you will have no suspension travel and will be jarring the bumpstops in the rear. The only other thing that makes contact is the aftermarket Tqarms where they attach to the diff- HOWEVER, this area will clearance itself adn punch a perfectly shaped hole in the floorboead up under the rear seat that you can eiter leave alone, or cover with sheetmetal, cover with dynomat etc, or cover with fiberglass.
The bumpstops need to be trimmed it rear stagnant rde height is under 26.5". Mine rode at 25 7/8" and I had to clearance them by 1st) shaving them in half vertically, and 2nd) retapering the sides into the original shape of a pyramid with a rotory sander to get the top surface area more of a point rather than a blunt impact.
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
My car is lowered 1.75" from the stock ride height and i never had a problem with the suspension travel, torque arm or the bump stops. I had to remove them for clearence for the rim.
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Thread Starter
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From: Southern Middle Tennessee
Car: 1986 Black IROC
Engine: 305 Quadrajet
Transmission: 5 speed
Axle/Gears: 273
Re: bump stops
Found answer.
Last edited by hartsmike; Feb 25, 2011 at 01:45 PM. Reason: found answer
Thread Starter
Member
Joined: Feb 2008
Posts: 306
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From: Southern Middle Tennessee
Car: 1986 Black IROC
Engine: 305 Quadrajet
Transmission: 5 speed
Axle/Gears: 273
Re: bump stops
I've heard lots about them on aftermarket wheels on both third and fourth gens.
Thread Starter
Member
Joined: Feb 2008
Posts: 306
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From: Southern Middle Tennessee
Car: 1986 Black IROC
Engine: 305 Quadrajet
Transmission: 5 speed
Axle/Gears: 273
Re: bump stops
This is what I had to do to put in a 15x10 6.5 BS rim with a 275/60/15 tire.
https://www.thirdgen.org/forums/whee...get-15x10.html
https://www.thirdgen.org/forums/whee...get-15x10.html
Good pics!! So, is it for the wider wheels to fit or the suspension to allow the axle up further?
Supreme Member
Joined: Feb 2010
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From: Orlando
Car: 1991 Camaro Z28
Engine: 357, Canfield heads, solid roller,
Transmission: Upgraded 03 Cobra T56
Axle/Gears: 9" 3.50 gears and Detroit Locker
Re: bump stops
Me too. I was on Eibach Sportlines for a while and never had a very harsh ride because of the bumpstops. My Spohn torque arm is definitely making contact though.
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Re: bump stops
Let me ask you the oh so obvious then. Since you never had this problem and this works for you then you have a right to list a fact that the ONLY reason to remove the bump stops is for wider 15x10 wheels? Just because you aren't low enough to hit them with your 1.75" lower then NOBODY ELSE WILL EVER? Are you kidding me?
Partner, your car is a 4x4 compared to mine. My car would turn circles on yours in a way that you have no comprehension of. You have no cluye what you are talking about when you try and post your INACCURATE facts and then come back into here defending them. You are wrong, these cars can and do hit them it not properly reengineered adn with great ride quality that low if done correctly....but you know nothing of that since you have never done this...but hey, your car is 1.75" lowered....lowered from what, a power wagon ride height?
Supreme Member
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From: Rochester NY
Car: 1984 z28
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Axle/Gears: Moser 9" 4.11
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From: Everett, WA
Car: 87' IROC
Engine: L98
Transmission: T56
Re: bump stops
With stock springs there is less than 2" of travel before the bump stops hits. If you are really lowered 1.75" you only had 0.25" of rear suspension compression travel.
Supreme Member
Joined: Apr 2006
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
And still you come back into here with your naiveness.
Let me ask you the oh so obvious then. Since you never had this problem and this works for you then you have a right to list a fact that the ONLY reason to remove the bump stops is for wider 15x10 wheels? Just because you aren't low enough to hit them with your 1.75" lower then NOBODY ELSE WILL EVER? Are you kidding me?
Partner, your car is a 4x4 compared to mine. My car would turn circles on yours in a way that you have no comprehension of. You have no cluye what you are talking about when you try and post your INACCURATE facts and then come back into here defending them. You are wrong, these cars can and do hit them it not properly reengineered adn with great ride quality that low if done correctly....but you know nothing of that since you have never done this...but hey, your car is 1.75" lowered....lowered from what, a power wagon ride height?
Let me ask you the oh so obvious then. Since you never had this problem and this works for you then you have a right to list a fact that the ONLY reason to remove the bump stops is for wider 15x10 wheels? Just because you aren't low enough to hit them with your 1.75" lower then NOBODY ELSE WILL EVER? Are you kidding me?
Partner, your car is a 4x4 compared to mine. My car would turn circles on yours in a way that you have no comprehension of. You have no cluye what you are talking about when you try and post your INACCURATE facts and then come back into here defending them. You are wrong, these cars can and do hit them it not properly reengineered adn with great ride quality that low if done correctly....but you know nothing of that since you have never done this...but hey, your car is 1.75" lowered....lowered from what, a power wagon ride height?
Supreme Member
Joined: Apr 2006
Posts: 1,801
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
Wrong. Your car just rode like crap and you didn't know it was because of the bumpstops. You were hitting the bumpstops on every imperfection. Mine rode like crap too until I trimmed my rear bumpstops.
With stock springs there is less than 2" of travel before the bump stops hits. If you are really lowered 1.75" you only had 0.25" of rear suspension compression travel.
With stock springs there is less than 2" of travel before the bump stops hits. If you are really lowered 1.75" you only had 0.25" of rear suspension compression travel.
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From: Everett, WA
Car: 87' IROC
Engine: L98
Transmission: T56
Re: bump stops
Who said anything about worn springs. Sorry but there is no way you can tell me the bump stops never hit if you only have 0.25" of travel. What rate springs were you running in the back?
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Re: bump stops
Oh, Imma gonna have fun with this guy....
Ok brain surgeon. Here's your car from the other post with Mickey T tires that are 275/60-15 with an overall height of what? gee 28"? wow low already. Then look at the picture where it shows you tire tucked under the fender well with a joe dirt ride height of maybe another 4" gap between the tire and fender lip? now we are at 32" to fender lip.
And then you state: You have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PMYou have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PM"You have no clue where my ride height was before and you have no clue how low it is now"
Well Alex Trebek, the question is:What is 1.75" higher than you have now"?
Trebek," Yes, you are amazing"
me" Well Alex, the brain surgeon did state that answer right up top a few posts where he shows a picture and a tire size and then states the obvious that its now 1.75" lower.
Ain;t stupid fun?
Ok brain surgeon. Here's your car from the other post with Mickey T tires that are 275/60-15 with an overall height of what? gee 28"? wow low already. Then look at the picture where it shows you tire tucked under the fender well with a joe dirt ride height of maybe another 4" gap between the tire and fender lip? now we are at 32" to fender lip.
And then you state: You have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PMYou have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PM"You have no clue where my ride height was before and you have no clue how low it is now"
Well Alex Trebek, the question is:What is 1.75" higher than you have now"?
Trebek," Yes, you are amazing"
me" Well Alex, the brain surgeon did state that answer right up top a few posts where he shows a picture and a tire size and then states the obvious that its now 1.75" lower.
Ain;t stupid fun?
Last edited by Vetruck; Mar 29, 2011 at 11:58 PM.
Supreme Member
Joined: Apr 2006
Posts: 1,801
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
Oh, Imma gonna have fun with this guy....
Ok brain surgeon. Here's your car from the other post with Mickey T tires that are 275/60-15 with an overall height of what? gee 28"? wow low already. Then look at the picture where it shows you tire tucked under the fender well with a joe dirt ride height of maybe another 4" gap between the tire and fender lip? now we are at 32" to fender lip.
And then you state: You have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PMYou have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PM"You have no clue where my ride height was before and you have no clue how low it is now"
Well Alex Trebek, the question is:What is 1.75" higher than you have now"?
Trebek," Yes, you are amazing"
me" Well Alex, the brain surgeon did state that answer right up top a few posts where he shows a picture and a tire size and then states the obvious that its now 1.75" lower.
Ain;t stupid fun?
Ok brain surgeon. Here's your car from the other post with Mickey T tires that are 275/60-15 with an overall height of what? gee 28"? wow low already. Then look at the picture where it shows you tire tucked under the fender well with a joe dirt ride height of maybe another 4" gap between the tire and fender lip? now we are at 32" to fender lip.
And then you state: You have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PMYou have no clue where my ride height was before and you have no clue how low it is now. Today 12:19 PM"You have no clue where my ride height was before and you have no clue how low it is now"
Well Alex Trebek, the question is:What is 1.75" higher than you have now"?
Trebek," Yes, you are amazing"
me" Well Alex, the brain surgeon did state that answer right up top a few posts where he shows a picture and a tire size and then states the obvious that its now 1.75" lower.
Ain;t stupid fun?
Guest
Posts: n/a
Re: bump stops
Ok Im the moron, I will accept that. So now lets recalculate.
32" fender lip MIIINNUUUSSS 1.75" rrriiiigggghhhttt? equals 30 1/4" fenderlip. Its a far cry from my 25 7/8" fenderlip.
Like I said, you have no clue. If your factory bumpstops were still on their (not to mention the compromised integrity of your chassis) you would still have 3 3/4" travel until you touch the factory bumpstop.
You have a lowered car? Maybe for Arkansas hillbilly standards, but I have no clue about that. I am sure you will enlighten us further.
32" fender lip MIIINNUUUSSS 1.75" rrriiiigggghhhttt? equals 30 1/4" fenderlip. Its a far cry from my 25 7/8" fenderlip.
Like I said, you have no clue. If your factory bumpstops were still on their (not to mention the compromised integrity of your chassis) you would still have 3 3/4" travel until you touch the factory bumpstop.
You have a lowered car? Maybe for Arkansas hillbilly standards, but I have no clue about that. I am sure you will enlighten us further.
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Re: bump stops
And still you come back into here with your naiveness.
Let me ask you the oh so obvious then. Since you never had this problem and this works for you then you have a right to list a fact that the ONLY reason to remove the bump stops is for wider 15x10 wheels? Just because you aren't low enough to hit them with your 1.75" lower then NOBODY ELSE WILL EVER? Are you kidding me?
Partner, your car is a 4x4 compared to mine. My car would turn circles on yours in a way that you have no comprehension of. You have no cluye what you are talking about when you try and post your INACCURATE facts and then come back into here defending them. You are wrong, these cars can and do hit them it not properly reengineered adn with great ride quality that low if done correctly....but you know nothing of that since you have never done this...but hey, your car is 1.75" lowered....lowered from what, a power wagon ride height?
Let me ask you the oh so obvious then. Since you never had this problem and this works for you then you have a right to list a fact that the ONLY reason to remove the bump stops is for wider 15x10 wheels? Just because you aren't low enough to hit them with your 1.75" lower then NOBODY ELSE WILL EVER? Are you kidding me?
Partner, your car is a 4x4 compared to mine. My car would turn circles on yours in a way that you have no comprehension of. You have no cluye what you are talking about when you try and post your INACCURATE facts and then come back into here defending them. You are wrong, these cars can and do hit them it not properly reengineered adn with great ride quality that low if done correctly....but you know nothing of that since you have never done this...but hey, your car is 1.75" lowered....lowered from what, a power wagon ride height?
. Keep your ego on the track like everyone else. Guest
Posts: n/a
Re: bump stops
You have a 28" tall tire on there and you can see its flush at the very least with the fender lip. So at minimum you have 1 1/2" travel before you hit the factory bumpstop, I will say more like 2 to 2 1/2" since It looks like about a 1/2 to 1" gap (picture is dark but I ca definately see tread so its not lower than the tire height.
THis post is about bumpstops and people needing to reshape them for lowered cars...Or did you not understand that point of topic?
THis post is about bumpstops and people needing to reshape them for lowered cars...Or did you not understand that point of topic?
Last edited by Vetruck; Feb 25, 2011 at 03:00 PM.
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Re: bump stops
I post facts and stats, If that makes me arrogant in your opinion? I can't help your insecurity.
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From: Everett, WA
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Re: bump stops
People local tp me know not to spew bullshit like you are doing or their pocketbook will be lighter. I sucker punks like you in. Lets see you post some positive info people can use, or maybe some statistics that are factual and impresive? Lets see your dick son
Last edited by Vetruck; Feb 25, 2011 at 03:26 PM.
Supreme Member
Joined: Apr 2006
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
I stated what i did and actually agreed with you in my other post but you keep talking just to hear yourself talk.
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From: USA
Car: 1989 SS
Engine: LT1+1500$ hooker exhaust
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Axle/Gears: 3.42 bogger
Re: bump stops
So what is it call what you are doing right now. Show me where you help educate people around here. My contributions around here spekl for themself not to mention my credentials. Funny you say suchh things, ever check my profile link? Didn't think so or you would not have stepped on your dick
People local tp me know not to spew bullshit like you are doing or their pocketbook will be lighter. I sucker punks like you in.
People local tp me know not to spew bullshit like you are doing or their pocketbook will be lighter. I sucker punks like you in.
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Re: bump stops
This post isnt about reshaping bump stops for lowered cars. The OP asked what they are, where are they and why you would remove them. What do you not understand ??
I stated what i did and actually agreed with you in my other post but you keep talking just to hear yourself talk.
I stated what i did and actually agreed with you in my other post but you keep talking just to hear yourself talk.

Lets quote the opening post about cutting bumpstops- What on god's green earth do you think cutting referes to? duh reshaping maybe you cut the rubber and reshape it, you don;lt remove it...
[ "I've read lots about cutting bump stops but don't know what they are, where they are and what it does to cut them and how to cut them...
Can anybody give me this information?
Thanks "]
For the RECORD, I am the ONLY PERSON to answer the original question on this thread so far. I even gave the ride height they can go safely until the bumpstops need reshaping..
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Re: bump stops
But to keep it on topic: I think that if you don't know what bump stops are or where they are or what they do then maybe you shouldn't be modifying your suspension until you do.
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Joined: Apr 2006
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From: Rochester NY
Car: 1984 z28
Engine: 355
Transmission: 700r4
Axle/Gears: Moser 9" 4.11
Re: bump stops
That's what it was. Keep trying pat yourself on the back. You might have a contributed something but your not the only person. Cutting out the bump stops and reshaping are two different things. Cutting out means the bump stop is gone, reshape means to rework or shape differently. Keep trying.
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Re: bump stops
Getting back on topic, my car with stock tire size and stock rear suspension was 27.5" on the rear left and 28" on the rear right. It WOULD hit the bump stops.
Now, with new stock height springs and new rear shocks, the car sits at 28.5" on both sides. It doesn't hit the bump stops unless there is some obscene crater in the road.
If you're wondering what bump stops are, get down on the ground behind the rear wheels and take a look for a triangle shaped rubber block. Once the car compresses down, the bump stop will prevent the car from going down any farther. Pretty much the suspension of last resort.
Here is a picture of my stock bump stop. (still on there, picture is a few years old.....to the left of the spring). That is the driver's side rear tire.

Not much room for suspension travel if you have lowering springs. I can't say for sure that people who have 1.75" lowering springs are or aren't hitting the bump stops as I haven't tried it. But even Eibach has said that their Sportline springs are meant to use the bump stops due to their soft spring rate. I suspect this is why a lot of people on TGO complain about poor ride quality with Eibach Sportline springs.
Now, with new stock height springs and new rear shocks, the car sits at 28.5" on both sides. It doesn't hit the bump stops unless there is some obscene crater in the road.
If you're wondering what bump stops are, get down on the ground behind the rear wheels and take a look for a triangle shaped rubber block. Once the car compresses down, the bump stop will prevent the car from going down any farther. Pretty much the suspension of last resort.
Here is a picture of my stock bump stop. (still on there, picture is a few years old.....to the left of the spring). That is the driver's side rear tire.

Not much room for suspension travel if you have lowering springs. I can't say for sure that people who have 1.75" lowering springs are or aren't hitting the bump stops as I haven't tried it. But even Eibach has said that their Sportline springs are meant to use the bump stops due to their soft spring rate. I suspect this is why a lot of people on TGO complain about poor ride quality with Eibach Sportline springs.
Thread Starter
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From: Southern Middle Tennessee
Car: 1986 Black IROC
Engine: 305 Quadrajet
Transmission: 5 speed
Axle/Gears: 273
Re: bump stops
So... Removal of the bump stop allows the chassis of the car to travel further "down"? Will that allow the car to bottom out in spost such as the tank etc....?
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