Novak Conversions Jeep Wrangler TJ engine mounts

Most reliable inline-6 engines

I had a BMW 3.0 CS for a few years, the motor was great but they had issues with the camdrive snaping the ears off.

Still have one of the special cam nuts they sold to correct the problem in my toolbox.

Pfft kids write about engines IH Black Diamond was one of the most reliable sixes ever built.
 
Was surprised not to see the Toyota 2F on that list. It was basically a forklift motor that powered the later FJ40 and the FJ60. Good to see the Ford 300 I6 on the list though, I really enjoyed my Bronco with that engine. Between the 2F, the Ford 300, and my experience with the 4.0 HO in my XJ, all back in the day, I didn't want anything except an I6 in my off road vehicle and I landed on the TJ.
 
Was surprised not to see the Toyota 2F on that list. It was basically a forklift motor that powered the later FJ40 and the FJ60. Good to see the Ford 300 I6 on the list though, I really enjoyed my Bronco with that engine. Between the 2F, the Ford 300, and my experience with the 4.0 HO in my XJ, all back in the day, I didn't want anything except an I6 in my off road vehicle and I landed on the TJ.

Interesting you mentioned the 2F. I've had several FJ40s and 60s with that engine and you couldn't kill those things. Absolutely bulletproof!
 
My folks had a Valiant with the push button automatic.

We had an old Plymouth that had it. Metal dash too.

Now our Lincoln Nautilus has a pushbutton auto.

Funny how things come back around.

Back on topic, I can’t think of any inline cast iron engine that is not dependable.

The inline 6 in the Chevy Trailblazer is more the engine a JKU should of had.

The 4.0 was a must for the TJ- honestly it was the only hope Chrysler had to maintain consumer confidence in the platform. They needed to keep the Jeep a viable product until they could figure out how to get it in the mainstream. They sure did both. To this day, the 4.0 is still the engine of choice as far as a stock powerplant.

In some ways it is perfect, in some ways frustrating.

To work as designed, the gearing, transmission and tires really need to work together- when that happens it is so good you don’t even think about.

Production changes have caused more grief than anything- the AX-15 and 32RH work better with it and most common tire sizes, on average, than any other transmissions Jeep has used.

Most owners that have never had one of those don’t know how good it can be mated to the right transmission.
 
Was surprised not to see the Toyota 2F on that list. It was basically a forklift motor that powered the later FJ40 and the FJ60. Good to see the Ford 300 I6 on the list though, I really enjoyed my Bronco with that engine. Between the 2F, the Ford 300, and my experience with the 4.0 HO in my XJ, all back in the day, I didn't want anything except an I6 in my off road vehicle and I landed on the TJ.

I think the 2jz and rb26dett both made it on the list due to being those companies most recent offerings and being used in iconic 90s cars. I won't argue that they weren't overbuilt and understressed, but I have a hard time buying absolute reliability with the complexity of belt driven DOHC and twin turbos vs the simple open-loop only EFI on a chain driven SOHC with half the HP/liter in the Nissan/Datsun L28.

Probably should have been the 2F and the L28, but you have to be middle aged at minimum to have owned an FJ or a 280Z.
 
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I think the 2jz and rb26dett both made it on the list due to being those companies most recent offerings and being used in iconic 90s cars. I won't argue that they weren't overbuilt and understressed, but I have a hard time buying absolute reliability with the complexity of belt driven DOHC and twin turbos vs the simple open-loop only EFI on a chain driven SOHC with half the HP/liter in the Nissan/Datsun L28.

Probably should have been the 2F and the L28, but you have to be middle aged at minimum to have owned an FJ or a 280Z.

I'm slowly coming around to the fact that I'm middle aged, but I don't like it.
 
I think the 2jz and rb26dett both made it on the list due to being those companies most recent offerings and being used in iconic 90s cars. I won't argue that they weren't overbuilt and understressed, but I have a hard time buying absolute reliability with the complexity of belt driven DOHC and twin turbos vs the simple open-loop only EFI on a chain driven SOHC with half the HP/liter in the Nissan/Datsun L28.

Probably should have been the 2F and the L28, but you have to be middle aged at minimum to have owned an FJ or a 280Z.

The earlier type F engine ( 1949 - 1974 ) was a knock off of Chevy 6 bangers starting in 1929. The 2F was just tweeks and larger bore to the F.
Really any early I-6 is reliable do to inherent engine balance and way under-stressed hp/cid. And I agree with you , belt driven twin turbos and longevity compared to a simplier design doesn't add up.
 
I think the 2jz and rb26dett both made it on the list due to being those companies most recent offerings and being used in iconic 90s cars. I won't argue that they weren't overbuilt and understressed, but I have a hard time buying absolute reliability with the complexity of belt driven DOHC and twin turbos vs the simple open-loop only EFI on a chain driven SOHC with half the HP/liter in the Nissan/Datsun L28.

Probably should have been the 2F and the L28, but you have to be middle aged at minimum to have owned an FJ or a 280Z.

Couldn't agree more. There is definitely a difference between overbuilt and reliable. RBs can make make a reliable daily driven 600-800hp with simple bolt ons (although I still think that chassis they were installed in is what made them so loved) but they needed regular attention and care. 2Js will make 1000+hp with just bolt ons as well, but man they like to eat coil packs and sensors even in stock form. For most of us who would get on a forum, research common issues, and fix them ourselves, it's just standard. To a soccer mom who thinks replacing a TPS is just as impossible as rebuilding an engine, something that runs forever in stock form with nothing more than dropping it off for oil changes, 4.0s are pretty reliable (although I wouldn't recommend trying to make 800hp from one).

I gotta admit I chuckled out loud when I saw the RB on that list.
 
I'm a big fan of the GMC 270/302. The 270 had a 22 yr production run and powered thousands of deuce and half's during the big one up until Vietnam. The 302 kicked ass on the V-8's of the time on the oval tracks. The 4.0 has many characteristics of the GMC 6.
 
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I think that L series Datsun was the only engine I've ever owned that was more simple than the 4.0.

It had an airflow meter and a couple of other EFI sensors but no O2s, no check engine light, no limp mode. Single overhead cam so there were no lifters or pushrods, just a camshaft right under the rocker arms. The valves had to be adjusted but it was a threaded adjuster, no shims, so it barely took more time than changing the oil.
 
What about the Chevy 250 and 292. I had the 292 in a 81 Chevy 3/4 ton 4X4. What a beast that truck was.

I had a 1979 Chevy 250 many years ago. I rebuilt it. It was a gutless turd. I should have just put a 350 in it. The 292 might have been a little better. My uncle had one and it ran for many years.
 
Novak Conversions Jeep Wrangler TJ engine mounts