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Old 09-09-2019, 04:22 PM   #1
evanlove
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Smile How far are factory bump stops from hitting normally?

Hello,

I have a 69 GMC 1/2 ton short bed with a 350 and ac and power steering (maybe all that matters).

I would like to lower the front by cutting the coil springs, and people say you can lower up to 3 inches without problems...

... but there are less than 3 inches to the bump stop now...

... wouldn't that be an issue?


It's all factory (heavy half ton maybe? ) and there's lots of room between the fender and tire that I'd like to close up, I just don't see how I could lower it 3 inches on the spring cut when the bump stop is about 2.5 inches away from hitting now.


Is there something I'm missing about the relationship of these parts?

Thanks

All is well

Evan
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Old 09-10-2019, 06:48 AM   #2
PGSigns
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Re: How far are factory bump stops from hitting normally?

I don't like to go more than 2" with just springs. Can lead to alignment issues. I have cut many a set of front springs and always started with half to a full wrap and see where it goes. I have 2" drop coils in the front of my 66 and I just cut an inch off the bump stop with the saws all when I did it.
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Old 09-10-2019, 09:22 AM   #3
Kudzupatch
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Re: How far are factory bump stops from hitting normally?

Quote:
Originally Posted by evanlove View Post
I would like to lower the front by cutting the coil springs, and people say you can lower up to 3 inches without problems...

... but there are less than 3 inches to the bump stop now...

... wouldn't that be an issue?
Yup! It would be constantly 'bottoming out' and hitting the bump stops and make for a horrible ride unless you only drive on really smooth streets.

My Suburban was lowered and notched but would still hit the stops on hard bumps and it was teeth rattling at highway speeds. Heck, at slow speed is you hit a big bump.

Contrary to what people said, you want as much travel as you can if you care about the ride. Less travel means more bottoming out.

Softer bumps stops can help cushion the blow but you still have to have some suspension travel. Since my Burb only bottomed out on hard blows and still had decent travel I added BelTech urethane bumps stops and it made a big difference. Still bottoms out and I would prefer more travel but it isn't practical to add anymore to it.
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Old 09-10-2019, 10:53 AM   #4
lolife99
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Re: How far are factory bump stops from hitting normally?

Low static drops require the removal of the bump stop bracket on the lower a-arm.
I like to save the "steering stop" part of that bracket so the spindle will have something to stop against.

The rear bumpstops are removed also.
More travel equals better ride quality.
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Old 09-12-2019, 06:45 PM   #5
evanlove
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Re: How far are factory bump stops from hitting normally?

Thanks for responding

So, if I cut 1 full coil from the front, is that about 2 inches drop?

Then shorten up the bump stop to get a little more travel.

Then do I need shorter shocks so they don't hit their limits and create another sudden stop?

If so, is there another application I can say I have to be able to look up and find the right length shocks that fit the shock mounts I already have...

... or do I need to modify the shock mounts?



Ride quality is definitely important to me. Comfort and enjoyability and actually I'd like quicker turning reactions with less body roll.

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Old 09-13-2019, 04:37 AM   #6
lolife99
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Re: How far are factory bump stops from hitting normally?

Stock shocks should be fine with only a 2” drop spring.
There are ways to answer your own question by bolting on the shock and measuring the amount of travel it has before bottoming out after installing the cut spring.

The best way to lower the front is with a drop spindle.
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