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finally pulled the trigger... chevy 350 zz6 swap for my '88 xj..

jmg222

NAXJA Forum User
NAXJA Member
Location
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Dropped in a 350 SBC into my '88 xj years ago, been itching to get something a bit more potent and modern. A blown head-gasket on the current SBC pushed me over the edge...

Picked up a zz6 long block last week, starting the swap this week, should be a relatively straight-forward swap.. will post pics as I go forward.

And to head off the inevitable question.. I didn't do an LS swap mostly to keep this easy.. the zz6 is exactly the same dimensions as my 350 and is a direct drop-in, and will use the same accessories so I know everything will fit as is... and performance wise, the zz6 pumps out pretty much the same power as an ls2 with similarly flat curve.
 
Old motor out:

2ch2o78.jpg



zz6 in:

2j0ytkl.jpg

2nukin8.jpg

25ryyz9.jpg
 
a few more pics:

30atmc9.jpg

2qlubug.jpg

ndk8eh.jpg

2q3w3df.jpg

qygu90.jpg
 
Very cool.

Is that your own space or a professional shop?

First gen f-body in the background?
 
Very cool.

Is that your own space or a professional shop?

First gen f-body in the background?


No.. it's a shop. wanted to do the swap myself in my home garage, but really just don't have the time or the patience... we did the original 350 swap, and it was a pita. The guy's overhead winch alone made it a million times easier.
I don't remember what he has behind me.. it believe it is a vintage Camaro .. guy has a ton of really nice cars he's working on, the space is huge; he's working on a '68 GTO, '57 chevy, there's a '65 'vette right off frame.. there's also a firebird and a vintage bronco off frame as well.
 
motor in and running... found some nice headers, and a gorgeous satin-black edlbrock intake :)

2n0q4bm.jpg

1411ca9.jpg
 
Looks good! How's it run compared to the old motor?

The old motor wasn't too bad, slightly rough idle, decent grunt on the bottom end but nothing crazy.

ZZ6 is silky smooth, and is like an animal when you hit the gas (not exactly what I need offroad, but fun). Haven't checked temps yet, but other guys I know run these things all day in XJ's with the same cooling setup I have with the AC on in the middle of summer and don't break 210.
 
installer sent me a (crappy, low res) video, but the sound is pretty cool.. heading there in the morning to check it out. I'll post some updates in the morning.

https://youtu.be/HSU1hSwK1Wg
 
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finally got around to doing final tune on the EFI and a few part throttle romps on the break-in, man this thing really pulls now!!
 
Soooo freakin awesome! Love that v8 rumble!!

Any plans to upgrade axles now? The 30/8.8 combo with that much tq spinnin 35" tires might not last long?

The 318 in my ZJ had some work into it.. Definitely less powah then you've got tho. I can't imagine how awesome your xj will be in 4low- my ZJ felt like it wanted to lift the front tires off the ground with any little brrrap of the skinny pedal

At least have spare axle shafts when you go wheeling... My 5.2 ate a handful.

Now I'm looking at my 4.sl0 with envy LMAO
 
Soooo freakin awesome! Love that v8 rumble!!

Any plans to upgrade axles now? The 30/8.8 combo with that much tq spinnin 35" tires might not last long?

The 318 in my ZJ had some work into it.. Definitely less powah then you've got tho. I can't imagine how awesome your xj will be in 4low- my ZJ felt like it wanted to lift the front tires off the ground with any little brrrap of the skinny pedal

At least have spare axle shafts when you go wheeling... My 5.2 ate a handful.

Now I'm looking at my 4.sl0 with envy LMAO

Thanks-- the 8.8 rear is already an upgrade, more than capable of handling the zz6. I doubt it'll go, but if it does... d60 I guess is the only upgrade left that'll really fit.
The front... eh... when it breaks, it breaks. new front axle has always been planned, but always getting pushed for other toys.
 
Oh for sure... We'd likely all be on 1 tons with 500hp if we could!

Lmao- i wasnt suggesting you need new axles... But if you are locked in either, with that mich power to the skinny pedal, grabbing a few jy spares might be a good reassurance.

Hp60/14bolt is the norm for most 1 ton setups.. And its pretty common to run 35s on the hp30/8.8 you have. Most would agree 37" tires is where those start to fall off. Of course thats without the 400tq.

44 front is a slight upgrade, debatable... 9" rear.. Same. 60s and above is probably overkill for 35s.... Just be aware of that power in binding situations was alls i was sayin
 
Oh for sure... We'd likely all be on 1 tons with 500hp if we could!

Lmao- i wasnt suggesting you need new axles... But if you are locked in either, with that mich power to the skinny pedal, grabbing a few jy spares might be a good reassurance.

Hp60/14bolt is the norm for most 1 ton setups.. And its pretty common to run 35s on the hp30/8.8 you have. Most would agree 37" tires is where those start to fall off. Of course thats without the 400tq.

44 front is a slight upgrade, debatable... 9" rear.. Same. 60s and above is probably overkill for 35s.... Just be aware of that power in binding situations was alls i was sayin

yeah, if I go bigger tires (not likely) I'll get a beefier rear... for now I'm just going to run it 'till something breaks . I've been fixing one thing or another for the past year and a half, time to actually run it (the suspension has less than 10 miles on it; tires have less than 100 miles).
 
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