ZZ4 to LS3 swap?
Thread Starter
Pro
Joined: Nov 2001
Posts: 534
Likes: 6
From: Cave Creek AZ
ZZ4 to LS3 swap?
I am considering pulling the ZZ4 in my 71 Convertible and swapping in an LS3. The ZZ4 has 4k miles on it, nothing wrong with it I would just be happier going full restomod and having a modern engine.
How much could I expect to get for the ZZ4? It has Edelbrock aluminum heads, intake & carb and MSD ignition.
Will my 5-Spd Tremec work well with the LS3?
How much labor would you think is involved in the swap? I won't be doing this myself, so am curious how many hours a speed shop will charge me.
Anything else I should consider??
How much could I expect to get for the ZZ4? It has Edelbrock aluminum heads, intake & carb and MSD ignition.
Will my 5-Spd Tremec work well with the LS3?
How much labor would you think is involved in the swap? I won't be doing this myself, so am curious how many hours a speed shop will charge me.
Anything else I should consider??
Team Owner
Joined: Feb 1999
Posts: 34,455
Likes: 665
From: Republic of Texas
https://www.corvetteforum.com/forums...-their-c3.html
Team Owner
Joined: Feb 1999
Posts: 34,455
Likes: 665
From: Republic of Texas
They're are lots of small items in addition to just the engine that add up and more importantly "time" AKA Labor. At $75-$100/hr, you're looking at $15-20,000 for a LS3 and to have someone do all the work ... at least in my area.
Last edited by Corey_68; Dec 13, 2015 at 11:14 PM.
Thread Starter
Pro
Joined: Nov 2001
Posts: 534
Likes: 6
From: Cave Creek AZ
I figure around 6-8k for the ls3 engine, hopefully get some of that back selling the ZZ4, then labor and other misc parts like the mounts, fuel system, harness and gauges. 15k would be my upper end beyond that and I would stay as is.
I am not satisfied with the current config due to the big lopey cam, and loads of unburned fuel going out the exhaust. As an alternative can I tone down the cam and add fuel injection to the zz4?
I am not satisfied with the current config due to the big lopey cam, and loads of unburned fuel going out the exhaust. As an alternative can I tone down the cam and add fuel injection to the zz4?
Last edited by DSchaefe; Dec 13, 2015 at 10:51 PM.
Team Owner
Joined: Feb 1999
Posts: 34,455
Likes: 665
From: Republic of Texas
I figure around 6-8k for the ls3 engine, hopefully get some of that back selling the ZZ4, then labor and other misc parts like the mounts, fuel system, harness and gauges. 15k would be my upper end beyond that and I would stay as is.
I am not satisfied with the current config due to the big lopey cam, and loads of unburned fuel going out the exhaust. As an alternative can I tone down the cam and add fuel injection to the zz4?
I am not satisfied with the current config due to the big lopey cam, and loads of unburned fuel going out the exhaust. As an alternative can I tone down the cam and add fuel injection to the zz4?
I pulled the BB and put in a low mile LS2/6 speed and never looked back. I would get in and drive this car across country tomorrow.
An aftermarket fuel injection setup would be the cheapest option, they have come a long way. The ZZ4 is great engine, especially with a 5speed. If it has low miles, I'd consider a cam swap and F. I. unit. It's a lot less involved and lighter on the wallet.
With that said, if you know you want the LS setup, don't settle as you will not be satisfied with anything less.
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Drifting
Joined: Mar 2004
Posts: 1,452
Likes: 40
From: Panama City Beach, Florida
I swapped in an LS1 to my '77, I had bought a wrecked 2004, took the motor and the computer, radiator, fans, clutch and sold the rest.
I did this way back before anyone was making a kit or motor mounts. I fabbed things I needed out of cardboard and took them to a friend who made me the real things. I bought a 6 speed from a Camaro ($1000).
Easiest swap I ever did - basically everything fit. I did it in my garage at home with help from my friends.
Started the motor on a thursday, left for the Bonneville Salt Flats Sunday, 137 mph on Tuesday.
Of course if you are paying someone else it will depend on how good they are.
Best - most fun - thing I've done in my meager car building career - Have not touched a thing since, repair wise.
PM me with any questions you think I can help with.
Happy Motoring, Frank
I did this way back before anyone was making a kit or motor mounts. I fabbed things I needed out of cardboard and took them to a friend who made me the real things. I bought a 6 speed from a Camaro ($1000).
Easiest swap I ever did - basically everything fit. I did it in my garage at home with help from my friends.
Started the motor on a thursday, left for the Bonneville Salt Flats Sunday, 137 mph on Tuesday.
Of course if you are paying someone else it will depend on how good they are.
Best - most fun - thing I've done in my meager car building career - Have not touched a thing since, repair wise.
PM me with any questions you think I can help with.
Happy Motoring, Frank
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I have an LS3 in my 72 Vette and it was quite costly. I did it myself and it was still very pricey. As for a fuel injection on a Gen 1 I ran a Mass flo on a 383 and it was pretty good. I currently have the EZ EFI 2.0 on order right now for my 408ci that is 550 HP in my Cobra. The 2.0 is supposed to be better since it has 8 injectors Instead of 4 for the previous system. I'll let you know how it runs. You do need the correct cam as one with to much overlap throws a lot of raw fuel into the exhaust causing the O2 sensor to see a rich condition. It tends to lean it out to much when cruising. I had to change the cam in y 383 and it ran much better. Right now awaiting a new cam and the 2.0 system.
Burning Brakes
Joined: Oct 2009
Posts: 1,066
Likes: 57
At idle, just how much more lopey is your cam compared to mine?
Is your ZZ4 the 355HP/450Tq. engine, or has it been modified?
Thanks
Race Director
Joined: Apr 2003
Posts: 19,353
Likes: 654
From: Tampa, Florida
I'm going to do the same thing...swap an LS3 into my '70.
Local shops want anyhwhere from $1500 to $3000 to pull the existing SB/muncie combo and drop in an LS3/T56. The cost includes setting the motor mounts, installing a new tranny crossmember and hooking up the exhaust to the LS3 manifolds. Parts not included.
Everything else I want to myself, partialy to save money and partialy becaue I like working on my car.
There are a lot of misc items that can run the bill up, way up, it all depends.
Use existing radiator. FREE
Use Dewitts custom LS conversion radiator. $600
Use a salvage LS3/T56 combo. $5-8000
Use a GM connect n cruise LS3/T56 combo $11-14,000
Connect n cruise combo comes with a harness and controller so no expense there but it has no front drive accessories so thats another $800
Salvage LS3/T56 comes with front drive accessories but you'll need to do something with harness/controller.
Fuel system. Spring for a new tank with an in tank pump or save money with a external pump?
Local shops want anyhwhere from $1500 to $3000 to pull the existing SB/muncie combo and drop in an LS3/T56. The cost includes setting the motor mounts, installing a new tranny crossmember and hooking up the exhaust to the LS3 manifolds. Parts not included.
Everything else I want to myself, partialy to save money and partialy becaue I like working on my car.
There are a lot of misc items that can run the bill up, way up, it all depends.
Use existing radiator. FREE
Use Dewitts custom LS conversion radiator. $600
Use a salvage LS3/T56 combo. $5-8000
Use a GM connect n cruise LS3/T56 combo $11-14,000
Connect n cruise combo comes with a harness and controller so no expense there but it has no front drive accessories so thats another $800
Salvage LS3/T56 comes with front drive accessories but you'll need to do something with harness/controller.
Fuel system. Spring for a new tank with an in tank pump or save money with a external pump?
Melting Slicks
Joined: Jan 2012
Posts: 3,041
Likes: 505
From: myrtle beach sc
Army
Gordonm, thank you for your reply.
Drspencer, I have the standard ZZ4 cam and it is not lopey at all! Either you have the optional high performance GM ZZ4 cam (which I have never heard), or someone changed it along with the heads and intake. I miss my lopey L-79 cam!!! Lou.
Drspencer, I have the standard ZZ4 cam and it is not lopey at all! Either you have the optional high performance GM ZZ4 cam (which I have never heard), or someone changed it along with the heads and intake. I miss my lopey L-79 cam!!! Lou.
