I have a 73 vette coupe and received a new ZZ4 crate engine. I have removed the old 350 and auto trans and would like to know if anyone else has made this swap? If so did you run into any problems doing it? I would like to use the serpintine belt system supplied would this create and clearance problems? Also would it be easier to mount the transmission to the engine first or install the engine first? Any help would be appreciated.

 

Hi gmzz4crate,

I believe Binnie77 has a ZZ4 in his 77 vert, but it is connected to a Tremec 5 speed so that would be a little different. However as far as installing the engine I think most of that would be the same. You can check out his website at http://www.corvettec3.ca/index.htm or you probably could PM him with questions.

 

I installed a zz4 in my 71.
If you are talking about the surp system that comes on the zz4 turn key I have heard there might be clearance problems with A/C comp and the A arms.
Trans first and then engine.

 

Up in the stickies click on links to tech tips. Click on the tech tips for C3s and at the very bottom there is a link about the ZZ4 swap. it may help.

 

I installed a ZZ4 & Tremac together, much easier than separately.
Will need a short water pump.
Also, on my 70 with a Holly Street Avenger, would not clear the hood. Put on a L88 scoop.
Exhaust port openings are D shaped on ZZ4 and do not match your stock manifold. I got Hedman headers that match.
If you have a standard tranny, make sure you take off the flexplate that comes on the motor.

 

Do a search function. There's a lot of posts about installing a ZZ4. A lot of posts were by me. I have a ZZ4 with Serpentine belts in my 68.
The idler pully on the stock Serpentine kit will interfere with the upper control arm bracket on the passengers side. Solution, install the idler arm bracket upside down, and it's clear. (You'll have to take a grinder and take off a little of the bottom "meat" of the bracket to make it fit in the aluminum casting.)

The ZZ4 heads have D ports. You can use a square port header with no discernable loss of HP. (As cited to me by the man who heads up Edelbrocks intake design lab. He has a PhD in fluid dynamics from Cal Tech.) It's important to match intake manifold to cylinder head ports, but not so with cylinder head ports to exhaust manifolds due to the extreme energy of exhaust gases. Also, what I did was take a D port gasket, lay in down on my square port headers, mark the outline of the D port with a felt tip pen, and then grind to square ports into a very good matching shape of the D ports.

I gave the Serpentine kit iron water pump a toss and bought the equivalent aluminum water pump made by Edelbrock.

You'll have trouble getting the stock throttle cable to mount up to the ZZ4 Holley. If you can find a 69,70 LT1 carb throttle cable bracket, you're in luck. Otherwise people have adapted a Lokar bracket. Try the search function for this issue.

The ZZ4 intake manifold and the carb for the ZZ4 fit under my stock SB hood. I don't have AC, so I don't know if there's a problem with the AC compressor.

 

Just remembered another hitch.
My ZZ4 came with an electronic drive HEI Distributor, Had to buy a mechanical drive one to match original drive.
Summit would not exchange them so have electronic one for sale.