CJ8/TJ Hybrid build

[JL in CA]

First post, though it has been in the works for a while, very slowly. Originally started for my son to drive wehn he got his license. He turns 17 this week and has been driving for around 8 months... Time to hit the gas before his brother gets HIS license in September. Details as follows:

Year: 81
Model: CJ-8 / TJ Hybrid
Final/current tire size: 35"

Build details (all new unless noted):
-TKD hybrid CJ8/TJ frame
-Currie Crate Axles with E-lockers and 4.56 gears
Front High Pinion Dana 44, Vanco super 16 Brakes from Black Magic
Rear Currie Dana 60 with Bridge Kit, standard Explorer brakes
- Savvy Mid Arm Suspension (haven't decided on shocks yet)
- Atlas Transfer case (new for TJ driverside offset - replacing Dana 300)
- SM465 transmission (existing)
- Fiberglass Tub (existing)
- Fuel 18x9 wheels
- Nitto Terra Grappler G2 LT285/75R18 tires (basically 35 x 11.25 helps not be so wide a stance)
- Engine TBD - existing to start (4.2L with mopar MPI kit - we live in California so can't swap in an LS or anything. Maybe a stroker later).

Biggest challenge so far is adapting suspension brackets/geometry to work with the axles and frame. Many of the reference points for the Savvy kit are measured off TJ reference points. At this point its all tacked, ready to burn in but I would love to get Blaine to take a look first while changes are still relatively easy...

Ok, there - its officially started. I'll post some photos soon of the roller.

 

[rubclt]

I have a TDK Hybrid… one lesson is steering geometry… track bar and drag link angles… are you using an inverted Y or cross over?

 

[bigwalton]

Heck yes.

 

[JL in CA]

I have a TDK Hybrid… one lesson is steering geometry… track bar and drag link angles… are you using an inverted Y or cross over?

Haven't gotten that far yet - suggestions (maybe PM me)? I really like your project but not as much as my son - he has already asked me about a hemi, and wants to paint ours blue - both hard no's (CA is a no on the engine and our paint is just fine - no need to paint just for color).

I heard back from Blane yesterday on a brake question. I'm taking the Jeep to see him in the next few weeks before I (or rather a real welder) burn in the suspension brackets to make sure I'm not doing anything I regret before committing and sending to powder coat. I know he has an opinion on it. Honestly, I want a capable off road jeep BUT with a teenage driver, I want the best on road manners I can get on a lifted vehicle. Outside of a rotted frame, that's a lot of the reason for the hybrid and total rebuild/replace for all the running gear - and to teach my boys this stuff. Granted, I drove the old leaf spring, narrow track 8 on the Los Angeles highways for years as a daily driver from 1997 to 2009 (sheesh) but when I drive it now its feels unsafe at any speed, lol. I have a JK as my daily driver - first an '09 with 35's and now a '15 with 37's - those parking lot curbs don't stand a chance!

 

[rubclt]

Happy to use PM, the benefit of this site is the years of experience and lessons learned from others and passing it on…

Photos help… what knuckle do you have for passenger side? Or do you plan to replace?

 

[bigwalton]

Yeah, no reason not to keep it in the thread.

 

[JL in CA]

Happy to use PM, the benefit of this site is the years of experience and lessons learned from others and passing it on…

Photos help… what knuckle do you have for passenger side? Or do you plan to replace?

No problem. I just didn’t want to rehash something that may be on the site. And I see debated a lot when I looked it up.

The knuckles came with the Vanco 16” big brake kit I got from Black Magic. I’ll upload some build pics and pics of the brakes when I get a second to take some. Their site says the following:

• New Left and Right high strength Nodular Iron Dual Mode 15" / 16" Steering Knuckles

I welcome the input!

 

[JL in CA]

Posting some initial pics. Please excuse the “garage”. Unlike most of Los Angeles my garage at least has cars in it and hasn’t been converted to living space . The white jeep is the still drivable for now donor.

 

[JL in CA]

And some of the brakes: orange tie down is the driver side, green is passenger. (I used them to crank it down on the springs for approximate ride height loaded. Axles are only very roughy located and I don’t have the front truss tacked yet).

 

[gr8dain]

Oh man, this is going to be a great build. When I replaced my frame, I was looking at a TDK. Had I pulled the trigger, I would have done the TJ hybrid as well. But the deal on the used frame I got was too good to pass up.

The initial post about CA restricting the engines made me a little sad (OK, a lot). I assume it has to be a motor that would have come in the Jeep originally? That sucks. I have been through 2 4.2s. Technically in VA there is some restriction about newer motors swapped in, but I didn’t care to obey that law/rule as I don’t think it is enforced. And I run antique tags anyway. I guess I won’t be moving to CA when I retire.

 

[rubclt]

Looks great… I have the Vanco knuckles on my LJ with big brake kit… since you have this it will be easier to run the TJ inverted Y steering. Cross over would require new knuckle or modifications to knuckles. Next question is the front axle stock width? If so, you can use the Rockjock https://www.rockjock4x4.com/CE-9701

Depending on lift height, will set size for pitman arm.

The TDK frame is great and bolting in axles is fun… the drivability will be determined in the steering setup… I made a lot of adjustments here from trail and error and hopefully this is helpful.

 

[rubclt]

On lift height… the TDK Hybrid body mounts are welded to position the body and act like a two inch body lift. This is another area of a lot adjustments. I ended with two inch spring in rear and three in front with ACOS… https://jksmfg.com/products/front-a...-lj-cherokee-xj-comanche-mj-grand-cherokee-zj

 

[bigwalton]

On lift height… the TDK Hybrid body mounts are welded to position the body and act like a two inch body lift. This is another area of a lot adjustments. I ended with two inch spring in rear and three in front with ACOS… https://jksmfg.com/products/front-a...-lj-cherokee-xj-comanche-mj-grand-cherokee-zj

View attachment 108557

Doesn't look like you're running the integral hydraulic bumpstop, add it, you won't regret it. Those with the JKS JSpec lift on my LJ were AMAZING at speed on the dunes. I had to relearn how fast I could drive that thing once I went to that suspension.

I have a pair of the ACOS NIB that I've been hoarding in the basement that I never installed on the back of the LJ due to the fab it would have required with the lift I had on it...

 

[rubclt]

Doesn't look like you're running the integral hydraulic bumpstop, add it, you won't regret it. Those with the JKS JSpec lift on my LJ were AMAZING at speed on the dunes. I had to relearn how fast I could drive that thing once I went to that suspension.

I have a pair of the ACOS NIB that I've been hoarding in the basement that I never installed on the back of the LJ due to the fab it would have required with the lift I had on it...

I have planned to swap to the NIB version… I had the ones I installed in my parts pile… likely will do rear too…

 

[JL in CA]

I have planned to swap to the NIB version… I had the ones I installed in my parts pile… likely will do rear too…

I have bump stops - they came with the savvy kit I just didn’t put them on as it’s all coming back apart when the frame goes to powder coat. I do need to buy and locate a track bar bracket on the frame still too (thoughts?)

 

[JL in CA]

On lift height… the TDK Hybrid body mounts are welded to position the body and act like a two inch body lift. This is another area of a lot adjustments. I ended with two inch spring in rear and three in front with ACOS… https://jksmfg.com/products/front-a...-lj-cherokee-xj-comanche-mj-grand-cherokee-zj

View attachment 108557

With the fiberglass tub, it’s just a matter of cutting down (or not) the rubber mounting spacer material. It comes in a long tube of it. I have it pretty thick (body lift) on the stock frame so likely will just reduce it some on the TKD.

 

[JL in CA]

Oh man, this is going to be a great build. When I replaced my frame, I was looking at a TDK. Had I pulled the trigger, I would have done the TJ hybrid as well. But the deal on the used frame I got was too good to pass up.

The initial post about CA restricting the engines made me a little sad (OK, a lot). I assume it has to be a motor that would have come in the Jeep originally? That sucks. I have been through 2 4.2s. Technically in VA there is some restriction about newer motors swapped in, but I didn’t care to obey that law/rule as I don’t think it is enforced. And I run antique tags anyway. I guess I won’t be moving to CA when I retire.

Worse for me, it originally was a rolling 30 year exemption but it stopped in 2004 and was replaced with a set year - ‘75 or older. There has been ongoing talk about adding 5 years to assist the classic car market/builders. Will probably happen just as I drop a new 4.6 stroker in (passes sniffer with flying colors and visual as a stock 4.2) . I would be happy to just not have to smog it every year. Explaining the CA approved MPI kit is always an adventure and more than 1 smog shop has turned me away as not being worth the risk when they don’t understand all the paperwork I have showing it’s approved.

 

[Chamba]

It's little wonder why so many California residents are flocking to other states. Where does this madness all end?

 

[JL in CA]

Looks great… I have the Vanco knuckles on my LJ with big brake kit… since you have this it will be easier to run the TJ inverted Y steering. Cross over would require new knuckle or modifications to knuckles. Next question is the front axle stock width? If so, you can use the Rockjock https://www.rockjock4x4.com/CE-9701

Depending on lift height, will set size for pitman arm.

The TDK frame is great and bolting in axles is fun… the drivability will be determined in the steering setup… I made a lot of adjustments here from trail and error and hopefully this is helpful.

Stock width so I'll checkout and likely go with that Rockjock set-up.

Bolting in axles would have been fun except for that the frame came blank due to the midarm set-up (and the Savvy "kit" had a LONG lead time and zero instructions. Had I gone long arm or short arm, I would have had TKD set it up that way and I would probably be much further along. Now we own a welder (albiet a cheap one just so we could tack things on) but on the plus side, my son has done a lot of the tacking and welding isn't such a mystery to us! Its a great life skill I just never learned or had equipment to do. I still can't "weld" but I can use our metal glue gun just fine!

 

[sdsupilot]

I was under the impression that an emissions intact swap was legal in California. You just need to have it approved once then just a normal annual inspection thereafter. If thats the case a TBI 350 or pre 06 LS wouldn't be a difficult thing to get approved.