front coil conversion done [writeup/pics]

fatwreck · 10-13-2006, 02:57 PM

You can check out the full writeup here:
http://www.projectxj.com/mods/yj/coil.conversion.htm

I'll just give you the cliff notes here. Note: TNT Customs should have more information available on their website in the next week or so. They tell me that they have been gathering pictures and putting together prices from the last few kits they have sent out.

I have a few good reasons for wanting to do this mod. Having not owned a YJ before, I didn't realize how harsh the ride is. It bounces back and forth a lot and there are a lot of quirky handling characteristics going down the highway. A lot of that can probably be attributed to the SOA, dead front springs, and lack of trackbars, but whatever. I really wanted something a little better to use as a daily driver.

The stock front springs that were used for the SOA were bent and sitting lower than the rear RE 1.5" springs. So, I wanted to do something about that.

Also, you can see the crappy belly pan setup that the previous owner had used to go along with the NV4500. Even for a daily driver, that just wasn't on my list for what is acceptable.

Here you can see how bad the negative arch is in the front springs at full flex. The springs will not last long like this (like mine didn't).

Check out the complete setup that you get when you place an order with them. The new belly pan with internal supports and frame sleeves:

I think the only thing missing from this picture is the trackbar, but it is included:

I enlisted the help of a couple of friends and their shop for this project because I was under a time constraint for getting it finished. However, this could easily be installed in your garage over a weekend with a friend or two and a welder.

I started off by pulling the dana30 out of the vehicle:

They make the truss so it can really only go in one place. You just need to set your caster and call it good:

fatwreck · 10-13-2006, 02:58 PM

Everything fits together in a certain way to make it really easy to assemble. Once the truss is in place, then the coil buckets just sit right beside it.

Then the truss comes off, so the coil buckets can be fully welded.

Here I am installing the 1" body lift that was necessary to get the belly pan and NV4500 combo to sit flush with the bottom of the frame. Can you see how amused I am?

Torching off the old leaf spring mounts:

Stupid leaf springs:

The belly pan is similar to the XJ kit. It installs with a set of internal frame braces and frame sleeves. I think that is pretty damn important, considering your entire front suspension setup is now relying on your belly pan for stability.

Here is a picture of one of the braces:

It takes a little bit of time to figure out the placement of the holes, but it isn't bad. I was able to get them pretty close the first time. It may take a little bit of tweaking to get it all to line up though.

The upper coil mounts are really well thought out. Again, this part is almost idiot proof. They slide into place and are held there with the factory bumpstop bolt. You can't screw up the location at all. You just mark where they go on the frame, so you can clean it up for welding, and then you weld them into place.

From there, the arms and the track bar basically bolt in to place. Yeah, its time consuming to get it all lined up, but it isn't bad. There weren't a whole lot of pictures to take during this process. Plus, we were all basically under the vehicle trying to get it finished.

Finished setup:

fatwreck · 10-13-2006, 02:59 PM

Unfortunately, I wasn't able to see the true potential of the kit because I needed to relocate the brake lines to make them longer. I also need longer shocks. After I get those things figured out, I know it will flex like a champ.

My initial driving impression.....WOW! The ride quality is insane. I figured it would be worth while, but I didn't realize it would be this good. All of those kidney jarring bumps that I used to hit on the way home from work are so much smoother now. There is no more bouncing back and forth over the concrete joints anymore. And all of the quirky SOA handling characteristics are now gone. I couldn't be happier.

GrayT · 10-13-2006, 03:06 PM

Good to see that you're sticking with TNT products.

Guess you won't be on NAXJA much anymore, eh?

arbby · 10-13-2006, 03:17 PM

How much did that run ya? Looks nice and nice flex too.

fatwreck · 10-13-2006, 03:26 PM

Quote:

Originally Posted by GrayT

Good to see that you're sticking with TNT products.

Guess you won't be on NAXJA much anymore, eh?

I'll pop in every now and then and help out where I can. It's not like I lost all of my XJ knowledge.

fatwreck · 10-13-2006, 03:30 PM

Quote:

Originally Posted by arbby

How much did that run ya? Looks nice and nice flex too.

I don't know what the official price release will be yet. I think it will depend on what option(s) you get with it. I heard that they may offer it as a complete kit with a SOA rear setup in case you don't already have one.....or a coil conversion for the rear that works with the front. I wasn't ready to drop all that money on a rear setup just yet. Plus, I wanted to see how it would work this way first.

I measure it out and my shocks are 3" too short for where the limiting straps stop the droop of the suspension. Once I get new shocks, it will flex quite a bit more....and hopefully make the rear work more than it is right now.

GrayT · 10-13-2006, 03:48 PM

Quote:

Originally Posted by fatwreck

I'll pop in every now and then and help out where I can. It's not like I lost all of my XJ knowledge.

True. So uhh... why the "conversion" from the XJ to YJ?

Also... do you plan on doing rear coils?

**bryris** · 10-13-2006, 03:53 PM

My hat is off to you. That is quite a project. I am glad it worked out well.

fatwreck · 10-13-2006, 03:59 PM

Well, I sold the original projectxj.....because I'm in the process of moving to the midwest. Then I got another older one for a daily driver and easy wheeler. And then I found some guy on craigslist that was willing to trade me my daily driver for his YJ. And I always wanted one.....so, I did it. The problem comes in when you aren't satisfied with mediocrity. And before you know it, your daily driver turns into a pretty cool trail rig.

I may put the coils on the rear down the road....I haven't decided yet.

GrayT · 10-13-2006, 04:04 PM

Quote:

Originally Posted by fatwreck

Well, I sold the original projectxj.....because I'm in the process of moving to the midwest. Then I got another older one for a daily driver and easy wheeler. And then I found some guy on craigslist that was willing to trade me my daily driver for his YJ. And I always wanted one.....so, I did it. The problem comes in when you aren't satisfied with mediocrity. And before you know it, your daily driver turns into a pretty cool trail rig.

I may put the coils on the rear down the road....I haven't decided yet.

As yes... I love "the problem"

I had that same problem with my XJ. Bought it with 3" of lift, and 31's. It was cool for about, oh, a week? Lol. Then the modding began. Congrats on the YJ! I like mine a lot, but I also love my XJ. They're just two different worlds. I feel more comfortable on the trail (damage wise) in the YJ for some reason.

Can't wait to see what you turn the YJ into.

10-13-2006, 03:17 PM	#5
arbby Registered User Join Date: May 2006 Location: SW Ontario Posts: 908 Profile Gallery Classifieds My Jeeps iTrader Rating	How much did that run ya? Looks nice and nice flex too. __________________ [COLOR="Black"] [COLOR="Tan"]\|¯¯l[/COLOR][COLOR="Black"],[/COLOR][___][COLOR="Black"],[/COLOR] l---L--[COLOR="Gray"]O[/COLOR]lllllll[COLOR="Gray"]O[/COLOR]¬[/COLOR] [COLOR="Black"][B]()_) ()_)--[/B]o[B]-)_)[/B][/COLOR] Gone: 1993 YJ

Similar Threads
Thread	Thread Starter	Jeep Forums	Replies	Last Post
Need help, doing a front coil conversion	KMA Krawler	YJ Technical Forum	4	03-04-2009 07:56 PM
Wheeling the TNT Customs coil conversion [pics]	fatwreck	YJ Technical Forum	4	06-03-2007 08:31 AM
360 and coil conversion swap with pics. Here it is!	JOKER4INK	YJ Technical Forum	1	07-25-2006 08:47 PM
YJ front coil conversion	YJscott2	YJ Technical Forum	12	06-14-2006 09:11 PM
Chevy 4.3L Conversion Writeup?	boulderz	YJ Technical Forum	3	12-25-2004 08:27 PM

10-13-2006, 02:58 PM	#2
fatwreck Registered User Join Date: Dec 2004 Location: ottawa, il Posts: 433 Profile Gallery Classifieds My Jeeps iTrader Rating	Everything fits together in a certain way to make it really easy to assemble. Once the truss is in place, then the coil buckets just sit right beside it. Then the truss comes off, so the coil buckets can be fully welded. Here I am installing the 1" body lift that was necessary to get the belly pan and NV4500 combo to sit flush with the bottom of the frame. Can you see how amused I am? Torching off the old leaf spring mounts: Stupid leaf springs: The belly pan is similar to the XJ kit. It installs with a set of internal frame braces and frame sleeves. I think that is pretty damn important, considering your entire front suspension setup is now relying on your belly pan for stability. Here is a picture of one of the braces: It takes a little bit of time to figure out the placement of the holes, but it isn't bad. I was able to get them pretty close the first time. It may take a little bit of tweaking to get it all to line up though. The upper coil mounts are really well thought out. Again, this part is almost idiot proof. They slide into place and are held there with the factory bumpstop bolt. You can't screw up the location at all. You just mark where they go on the frame, so you can clean it up for welding, and then you weld them into place. From there, the arms and the track bar basically bolt in to place. Yeah, its time consuming to get it all lined up, but it isn't bad. There weren't a whole lot of pictures to take during this process. Plus, we were all basically under the vehicle trying to get it finished. Finished setup:

10-13-2006, 02:59 PM	#3
fatwreck Registered User Join Date: Dec 2004 Location: ottawa, il Posts: 433 Profile Gallery Classifieds My Jeeps iTrader Rating	Unfortunately, I wasn't able to see the true potential of the kit because I needed to relocate the brake lines to make them longer. I also need longer shocks. After I get those things figured out, I know it will flex like a champ. My initial driving impression.....WOW! The ride quality is insane. I figured it would be worth while, but I didn't realize it would be this good. All of those kidney jarring bumps that I used to hit on the way home from work are so much smoother now. There is no more bouncing back and forth over the concrete joints anymore. And all of the quirky SOA handling characteristics are now gone. I couldn't be happier.

10-13-2006, 03:06 PM	#4
GrayT Registered User Join Date: Jul 2006 Location: The Springs, CO Posts: 33 Profile Gallery Classifieds My Jeeps iTrader Rating	Good to see that you're sticking with TNT products. Guess you won't be on NAXJA much anymore, eh?

10-13-2006, 03:59 PM	#10
fatwreck Registered User Join Date: Dec 2004 Location: ottawa, il Posts: 433 Profile Gallery Classifieds My Jeeps iTrader Rating	Well, I sold the original projectxj.....because I'm in the process of moving to the midwest. Then I got another older one for a daily driver and easy wheeler. And then I found some guy on craigslist that was willing to trade me my daily driver for his YJ. And I always wanted one.....so, I did it. The problem comes in when you aren't satisfied with mediocrity. And before you know it, your daily driver turns into a pretty cool trail rig. I may put the coils on the rear down the road....I haven't decided yet.