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Swapping ZZ4 into my 92 Yukon

Blaze

Blaze

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Well, the 350 is dead, so a friend of mine is selling me a brand new ZZ4 for $2000. What will it take to swap this into my 92 Yukon? I want to retain the fuel injection and all. I know the majority of it is a swap and go, but what about the fuel system, TBI, etc? Any pointers? /forums/images/graemlins/thumb.gif
 
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Well, the 350 is dead, so a friend of mine is selling me a brand new ZZ4 for $2000. What will it take to swap this into my 92 Yukon? I want to retain the fuel injection and all. I know the majority of it is a swap and go, but what about the fuel system, TBI, etc? Any pointers? /forums/images/graemlins/thumb.gif

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Holy crap $2k is an awesome deal. I love my zz4, good score!! Cant help with the swap though just thought I would share my enthusiasm /forums/images/graemlins/histerical.gif
 
Most of your stuff should bolt right on you might have to get a new computer chip depending on the cam you are going to run
 
I have a ZZ4 IN my 86 burb.. Not fuel injected .. I think the heads line up diffrent on those then the 92.. The ZZ4 is for 95 TO 99 replacement.. I could be wrong thou...
 
You need to look at the heads where the intake bolts to it. The ZZ4 should not have Vortec style intake bolt pattern, but the TBI intake you have most likely has the center bolts at a slightly different angle than the rest. A little die grinder action on those holes on the intake and they should bolt up. Just make sure to look and compare closely!

Sweet deal by the way!
 
A ZZ4 does have vortec heads, it also has 10:1 compression and a cam that is too big for EFI.

I don't really think there is anything you can do on an EFI system with a MAP sensor to accomodate a cam that big, but maybe someone else will chime in with a solution.

I'd probably consider finding a Vortec injection system with a MAF sensor and working from there. OBD II is going to make that somewhat difficult though.
 
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How can you say the cam is to big for EFI... That is what that block was desined for..

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The ZZ4 is a high performance crate motor.

It was not designed to replace any stock engine and it is not emissions legal.

I don't know what you're getting at. Maybe you could explain?

Just because it has Vortec heads doesn't mean that it is a 96-99 replacement motor. It has aluminum heads too, that doesn't make it a corvette engine.
 
Actually the ZZ4 comes with the old (mid 80's-early 90's) aluminum corvette heads. I 'm not sure but i think the had the later, straighter intake center bolt angle. As for the cam, it looks big on paper but i've got 1 in my carbed 355 and it pulls 18-20" of vacuum at 850 rpm. Plenty for a MAP sensor. Makes big power all over too! My only complaint is the boring "stock cam" idle but it's the price paid for big low end torque.
 
My friend's brother said it would bolt up, but I'd need to upgrade my fuel system. Can't I just bolt up a 454 truck TBI to the ZZ4 intake and put a bigger fuel pump in there and it would be fine? I can easily get a computer chip burned for it, but I just want it to be an easier swap. I've seen a local guy with a 93 shortbed with a ZZ4 and a 454 TBI, but I never really got into how he swapped it. Just struck up a conversation with him at a stoplight, so no way I'll find him again.
 
Just wanted to chime in here: The ZZ4 does NOT have Vortec heads and the Vortec intake is different, but if you get the Fastburn 385 , you will have aluminum vortec heads.

The IROC MAF system is a bolt on if it is (IIRC) an 87 or earlier. Of course you are limited to 255 Liters of air or about 325hp since the MAF is 8 bit. You would do better to get the 16 bit LT4 FI system which is good to 425+ hp.

You can drill a couple of the intake bolt holes to fit if you get the wrong year FI system, and seal the bolt heads with RTV.

The spark plugs are angled, so you will need angle plug headers. Kind of a pain.

Great engine though. /forums/images/graemlins/wink.gif
Jeff /forums/images/graemlins/usaflag.gif /forums/images/graemlins/usaflag.gif
 
I am doin a zz4 engine swap in to a mid 80s buick regal at my shop right now. This engine is equipt with the fast burn cylinder heads and angled plugs.I am runnign a set of regular headers with no clearance problems .if you wanted to use a tbi intake the 4 center bolt holes would have to be modified as stated earlier. and i would see no problem running a 670cfm throttle body and getting a chip burned for it. The spec sheet only recomends a 650cfm carb.hope i was helpful /forums/images/graemlins/thumb.gif
 
Well, with the Fastburn heads, the ZZ4 stock dual plane intake won't fit and then it's not really a ZZ4 anymore. /forums/images/graemlins/wink.gifThe TBI from a vortec engine will fit with the Vortec syle fastburn heads.

Also on the exhaust side, the ZZ4 heads have the D shaped exhaust ports plus angled plugs. I don't know about the fast burn ones, but there tends to be plug wire burning with some regular style headers. It all depends on the bends which tend to be tight on the first gen trucks.
 
I agree that the 454 TBI will work just fine. That engine has a lot of cam, but not too much for even TBI.
 
Geez, tons of info here, but all so confusing!

I have a ZZ4, non-Fastburn, just plain old ZZ4. I was told that it will all bolt right up on the fullsize chevy board. Is this true? Grinding the old intake and that is it? Any definite answers? /forums/images/graemlins/rotfl.gif /forums/images/graemlins/rotfl.gif /forums/images/graemlins/rotfl.gif
 
I thought you would use a 454 TBI with spreadbore adapter from an 87-89 truck. That will bolt to your ZZ4 intake easily. /forums/images/graemlins/thumb.gif
 
Thanks, that is what I wanted to know! So all I need is a spreadbore adapter and it'll swap right up?
 
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