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loki_racer
August 19th, 2010, 09:28
I don't compete in JeepSpeed, but do compete in a different racing league that is similar to JeepSpeed.

I recently did a WJ knuckle conversion, TNT Customs trackbar and HySteer axle bracket. After the first race with this set, it quickly became apparent that I need some type of air bump.

How do I know if a 3" air bump will be enough to stop the track bar from contacting the oil pan? As a side note, what are some suggestions for nice "go fast" shocks that aren't adjustable?

chris_amrein
August 19th, 2010, 12:55
When you say "3 inch air bump" do you mean 3" of travel? Just curious because most air bumps are either 4" travel or 2" travel however you can add a spacer to them to get them at anything inbetween. What brand air bump are you looking at?

As far as clearance, the only way to be sure is to take out your coils and discharge the bumps down to very little presure and cycle your suspension.

Chris

loki_racer
August 19th, 2010, 12:58
3" of travel. I've been looking at the Light Racing JounceShock (http://www.rdmoffroad.com/lightracingjounceshocks.aspx).

I Beamed Jeep
August 19th, 2010, 14:59
Light racing bump stops work great!!! 3" travel bumps are fine you just have to mount them so at full bump the track bar doesn't hit the oil pan.

grandrunner
August 19th, 2010, 17:25
Fox 2.0s bumps are 2.5 stroke.. that's what I have

Cache96
August 19th, 2010, 17:26
Here is another option, alot cheaper than the light race bumps. I have heard good things about them, im going with these.

http://f-o-a.com/shop/index.php?main_page=product_info&cPath=20_44&products_id=25

dakineJ
August 19th, 2010, 17:33
Light racing bump stops work great!!! 3" travel bumps are fine you just have to mount them so at full bump the track bar doesn't hit the oil pan.
X2 , full bump is full bump no matter the bumpstop.

loki_racer
August 19th, 2010, 18:22
What's the best method for testing if the 3" will be enough? I guess if it's too short I can buy some of that white plastic stuff (can't remember the acryonom for it) and stack it on the axle spring perch to shorten the travel distance.

xcm
August 19th, 2010, 19:10
on a short travel suspension like the cherokee's, many prefer a shorter bumpstop travel.
If you have 4" of bumpstop travel, on a 10" shock, on a 50/50 setup, your tire goes up 1 inch, and youre shock's compression valving goes out the window. let the bumpstop do it's job, handling the last chapter of your suspension.

full bump is full bump, install them to sit where you need them to, you can allways add on spacers.

i have a thread on installing airbumbs, feel free to go check it out, it's not that difficult.

silverslk
August 19th, 2010, 21:40
What's the best method for testing if the 3" will be enough? I guess if it's too short I can buy some of that white plastic stuff (can't remember the acryonom for it) and stack it on the axle spring perch to shorten the travel distance.

Jim, I think there is a bit of confusion here. Do you have the link to when we set up your bumps?

RenegadeT
August 20th, 2010, 11:48
Here is another option, alot cheaper than the light race bumps. I have heard good things about them, im going with these.

http://f-o-a.com/shop/index.php?main_page=product_info&cPath=20_44&products_id=25
loki, these are the ones I was telling you about, but couldnt remember the names...cheap and include the mounting cans.

loki_racer
August 20th, 2010, 11:53
The thing I'm worried about with the can mounts like those (other companies have the same style mounts) is getting them mounted inside the spring. The Light Racing mounts are designed to be welded inside the spring.

I haven't been able to find any photos online of air bumps mounted on XJ's anywhere but inside the spring.

vetteboy
August 20th, 2010, 12:28
I used a piece of 2.5" OD x .25 wall tube inside the spring, and drilled/tapped a few holes for set screws to hold the bump in place.

silverslk
August 20th, 2010, 16:54
I haven't been able to find any photos online of air bumps mounted on XJ's anywhere but inside the spring.

Tony (TCM GLX) had them outside the spring. I'm sure he'll post up soon enough with some pics.

loki_racer
September 20th, 2010, 19:12
Anyone have any suggestions in dialing in the air bumps?

I bought the Barnett air bump mount kit and a set of Fox 4" air bumps. I understand how to mount the kit and bumps, but am unsure about how to ensure the bumps will stop my trackbar from striking my oilpan.

I don't want to lose functionality of the air bumps, but have to ensure they always stop my suspension from traveling up too much. Any suggestions?

GrimmJeeper
September 20th, 2010, 19:21
discharge your shocks and your airbumps (let out all the nitrogen), remove the coil springs, and compress the suspension to where you want it to stop. Mount your airbumps where they will be at full compression just before you reach that point.

loki_racer
September 20th, 2010, 19:24
You, sir, are a gentleman. Next question. How should I go about deciding how much nitrogen to run in the bumps? What type of "store" sells nitrogen? I know some tire dealers have nitrogen filling stations, but doubt they can get up to 150psi or so.

GrimmJeeper
September 20th, 2010, 19:27
A tire shop should have plenty of PSI, they are filling off a large bottle of nitrogen not compressing it themselves. Just don't put standard air in them, it will contain moisture and corrode them from the inside out.

I would contact whoever made your shocks and bumps and ask their advice on pressures. Different companies have different reccomendations.

GrimmJeeper
September 20th, 2010, 19:46
Make sure you're compressing the suspension evenly too, not one side at a time. Forgot to mention that.

loki_racer
September 20th, 2010, 19:50
Good point. Thanks.

Another question. Do I need to have a strike plate or is allowing the air bump teflon tip to strike the spring perk acceptable?

Sorry for all the questions, but I'm out on a limb with this stuff and haven't been able to google-fu any write-ups about it.

tbburg
September 20th, 2010, 19:51
Most shops that sell the high end shocks can also charge them. We have several 4WD shops around the valley here that will charge for free.

VAhasnoWAVES
September 20th, 2010, 20:01
Just don't put standard air in them, it will contain moisture and corrode them from the inside out.
saturation can be reduced to create "dry air".

the big problem with air (even though 70% of it is nitrogen) is that the other gasses compress and expand drastically under different temperatures. nitrogen does not have this characteristic, and thats why it is typically used. it provides the most consistent pressure under any condition.

just figured id throw a little chemistry out there. :) :conceited

crazyjim
September 20th, 2010, 20:33
http://teamvigilante.com/personal/jeep/bumps/IMG_0967.JPG





Compressing suspension to check bumps. Worked out perfect on my XJ before I tore it down.

GrimmJeeper
September 20th, 2010, 21:05
hmm i recognize that driveway... :D

silverslk
September 20th, 2010, 21:56
hmm i recognize that driveway... :D

Most people do!!! :cool:

I "used" to have a bunch of jeep a holes hanging out in/on it until I got a bronco,......now they don't come over anymore. :twak:


:laugh3:

GrimmJeeper
September 20th, 2010, 22:10
we figured you forgot how to work on jeeps... it's a ford after all it must keep you pretty busy :gag:

toyotawrench
September 20th, 2010, 23:33
Most people do!!! :cool:

I "used" to have a bunch of jeep a holes hanging out in/on it until I got a bronco,......now they don't come over anymore. :twak:


:laugh3:

you never invite us any more :( i need to put brakes on my 8.25 and put it in :D

peace
ted

Bajaflo99
September 20th, 2010, 23:37
Are you getting rid of the air bumps jim?

crazyjim
September 21st, 2010, 03:15
Are you getting rid of the air bumps jim?
Sold those long ago. I've got some new Bilstein air bumps going in!

Ryan93
September 21st, 2010, 10:27
Party at Andys house

silverslk
September 21st, 2010, 17:00
Party at Andys house

OFF MY LAWN YOUNG PUNK!!!! :nono:

haha. Hell yeah....you guys are welcome ANYTIME!!! (just not you Ted) :cheers:

GrimmJeeper
September 21st, 2010, 17:01
oh snap haha

Ryan93
September 21st, 2010, 17:21
BURN