ZZ6 EFI 350 Turnkey (1 Viewer)

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I am going to ask a few of the inevitable questions that come with any discussion about engine swaps:

Do you already have an SBC in your rig?
Why would you chose a 64 year old platform (GEN I or II) over a modern LS-based platform (Gen III or IV, like an 5.3 LM7)?
Are you concerned at all about overall fuel economy?
If you are looking at crate motors, did you do a cost/benefit analysis vs. an LS (i.e. fuel economy, engine life, etc.)?
What type of transmission would you be leaning towards?
How much horsepower/torque do you need, and is the rest of you 40 built to take it?
What type of off-road driving do you do?

The answers should help the discussion about this particular engine choice?
 
I am going to ask a few of the inevitable questions that come with any discussion about engine swaps:

Do you already have an SBC in your rig?

Yes a refurbished 350 4 bbl carb

Why would you chose a 64 year old platform (GEN I or II) over a modern LS-based platform (Gen III or IV, like an 5.3 LM7)?

Not sure I understand this... the zz6 is a new engine.

Are you concerned at all about overall fuel economy?
NO

If you are looking at crate motors, did you do a cost/benefit analysis vs. an LS (i.e. fuel economy, engine life, etc.)?
What type of transmission would you be leaning towards?

H45 4speed Stock

How much horsepower/torque do you need, and is the rest of you 40 built to take it?

It's had a 300 plus hp 350 engine in it for years.

What type of off-road driving do you do?

Moderate to daily driver

The answers should help the discussion about this particular engine choice?
 
The ZZ6 is a Generation II engine and relatively speaking, older technology.

Generation III & IV engines are represent the newest engine technology with much better diagnostic capabilities and longer lifespans.

Both will make your 40 go down the road.
 
The upside of the ZZ6 is most of your external accessories will bolt right up.
 
The ZZ6 is a Generation II engine and relatively speaking, older technology.

Generation III & IV engines are represent the newest engine technology with much better diagnostic capabilities and longer lifespans.

Both will make your 40 go down the road.
Do you have any suggestions on a Gen III or IV engine swap?
 
Has anyone out there had the privilege of installing one of these in their FJ 40?

ZZ6 EFI Deluxe Small-Block Crate Engine | Chevrolet Performance

If I were doing it I would go with BluePrint Engines 350CI Crate Engine | Small Block GM Style | Longblock | Iron Heads | Roller Cam as it is a warrantied (30 month, 50k) roller cam engine with the nice vortec heads that should be super durable/reliable, then throw something like a Holley Sniper on top and do timing control with their dizzy. It would get you to approximately the same place and be a nice clean system from name brands for likely less money ($3K+.)

Edit: that looks like direct injection rather than TBI in the sniper. I dont know if that is important to you or not.
 
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Do you have any suggestions on a Gen III or IV engine swap?

It's pretty straight forward and easy swap. If you've done a swap before, this will be pretty much the same.

The 5.3 and 6.0 are pretty typical choices. My personal preference is to use throttle by cable (versions up to 2002) rather than throttle by wire, just because the install is a bit easier. From a stock OEM perspective, pound for pound the Gen III and IV engines deliver more horsepower and torque. Built up just like the old SBC, your horsepower is pretty much limited by how much you want to spend. My 5.3 has all the power I need for crawling with a fully loaded rig.

GM E-Rod engines (new, in the crate) are nice smog legal choices if that's a factor where you live, and when on sale are in the $9,000 range. If it's a budget build I prefer to buy lien sale vehicles or wrecks with low mileage and take everything I need then sell the rest. I have had good luck with Howell EFI building my harnesses and reprogramming the PCM to delete everything except what it takes to run the engine. Reprogramming will delete tons of unnecessary error codes from vehicle equipment that no longer exists (seat belt alarms, etc.) and allows you to 'tell the engine' what you do have, like 37" tires, 4:11 gears, etc.

If smog is not an issue, then you won't need the cats, but you do want the 'up-stream' O2 sensor (Howell will adjust the programming accordingly).

The only mount I had to relocate was the rear trans mount, but I was able to make a minor adjustment to my Lokar shifter to get it to come out in the exact same location as before. The LSX engine adapters have 3 positions that allow you to move the motor to best fit your space.

Block hugger headers or OEM Corvette manifolds are necessary to get the exhaust inside the frame. Making dual exhaust easy.

Oil pan choice is important. I modified mine, but the OEM and Camaro pans work fine, The OEM LM7 pan is too deep.

OPINION ALERT! Gen III & IV do not use a dizzy. The PCM controls the spark and adjusts everything to accommodate the operational and environmental conditions you face to keep the engine running at its best. Combined with all the other engine sensors, it will run as smoothly at 8,000 feet as it will as sea level. This type of performance is hard to beat!

Now back to the rest of the story. LSX innovations (and others) make an adjustable adapter plate to bolt the Gen III directly into the same location as the old SBC. If you have a fan shroud, the Gen III fan will end up where it belongs.

Since the Gen III engines have been on the market for about 20 years, there is TONS of aftermarket support.

FWIW, I was a died-in-the-wool SBC guy until a 5.3 and 4L60e deal fell in my lap about 3 years. I absolutely regret waiting so long.

My personal favorite aspect of the Gen III and IV engines? Full diagnostic capabilities, Plug in the Scan Tool and you know exactly what's happening, and in real time as you are driving, if you want. Another plus, Howell can provide extra wires so the install of a Dakota Digital dash is even easier.

As I said, the Gen II and Gen III/IV will both get you 40 down the road. I would just encourage look at this thoroughly before you pull the trigger.
 

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