Engine Swap
Thread Starter
5th Gear
Joined: Oct 2021
Posts: 5
Likes: 0
From: Kentucky
Engine Swap
Hello all,
I just got my first corvette (1984 C4), and it has a locked up motor, I tried for a while to get it unstuck but it is locked up tight, there was a ton of water in the oil pan, valve covers were off for 15 yrs etc... I am looking to do a motor swap but also keeping it as original as possible and with the awesome gauge cluster working, with maybe a few smaller mods(camshaft, fuel pump, open for other suggestions as well
) What would be the easiest and most cost effective route to go? Was planning on going to a local junkyard and pulling a 350 from a 90s model chevy and swapping all the accessories over. Anything else that I need to look out for, tips or tricks? I am a young guy and this is my first project car and I am trying to learn as much as possible.
Thanks in advance!
I just got my first corvette (1984 C4), and it has a locked up motor, I tried for a while to get it unstuck but it is locked up tight, there was a ton of water in the oil pan, valve covers were off for 15 yrs etc... I am looking to do a motor swap but also keeping it as original as possible and with the awesome gauge cluster working, with maybe a few smaller mods(camshaft, fuel pump, open for other suggestions as well
) What would be the easiest and most cost effective route to go? Was planning on going to a local junkyard and pulling a 350 from a 90s model chevy and swapping all the accessories over. Anything else that I need to look out for, tips or tricks? I am a young guy and this is my first project car and I am trying to learn as much as possible.Thanks in advance!
Safety Car
Joined: May 2001
Posts: 4,741
Likes: 1,639
From: Fairfax Virginia
First things First, Welcome to the Corvette Forum Huskey411!
Are you planning on keeping the Corvette with it's Crossfire Injection System? There are lots of Cross fire experts on this site that can help you on this forum and some of them have really fast cross fire injected Corvettes!
You are going to have to "pull" the engine so I would pull it and tear it down to see what kind of condition it is in. You might be lucky and have minimum about of work needed. You might get away with a new short block or the motor might be trashed.
Are you planning on keeping the Corvette with it's Crossfire Injection System? There are lots of Cross fire experts on this site that can help you on this forum and some of them have really fast cross fire injected Corvettes!
You are going to have to "pull" the engine so I would pull it and tear it down to see what kind of condition it is in. You might be lucky and have minimum about of work needed. You might get away with a new short block or the motor might be trashed.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
Said it sat for 15 yrs was full of water
Op...headers, true dual exh (if you dont have smog), small cam work out good
PCM for less can tune it reasonably
There are aftermarket TPI intakes that flow better used...the superram isnt cheap but works great
Cams in the low to mid 2teens@050, 112-114lsa work great; A good valve job and bowl blend certainly help
Op...headers, true dual exh (if you dont have smog), small cam work out good
PCM for less can tune it reasonably
There are aftermarket TPI intakes that flow better used...the superram isnt cheap but works great
Cams in the low to mid 2teens@050, 112-114lsa work great; A good valve job and bowl blend certainly help
Last edited by cv67; Oct 11, 2021 at 12:20 PM.
Thread Starter
5th Gear
Joined: Oct 2021
Posts: 5
Likes: 0
From: Kentucky
I would like to keep the crossfire, I think its an interesting system and I am trying to keep the motor stock. I am pretty certain though that I am going to have to do a swap. I was mostly wondering things about a swap, like do I need to worry about certain years for the 350 that wont be a direct bolt in replacement, or anything like that.
Thread Starter
5th Gear
Joined: Oct 2021
Posts: 5
Likes: 0
From: Kentucky
Said it sat for 15 yrs was full of water
Op...headers, true dual exh (if you dont have smog), small cam work out good
PCM for less can tune it reasonably
There are aftermarket TPI intakes that flow better used...the superram isnt cheap but works great
Cams in the low to mid 2teens@050, 112-114lsa work great; A good valve job and bowl blend certainly help
Op...headers, true dual exh (if you dont have smog), small cam work out good
PCM for less can tune it reasonably
There are aftermarket TPI intakes that flow better used...the superram isnt cheap but works great
Cams in the low to mid 2teens@050, 112-114lsa work great; A good valve job and bowl blend certainly help
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
I would just go shopping for a crate engine either a 350 or 383 with aluminum heads. I would not waste time and money on originality. The CFI intake will require some porting to clean it up. The other choice is the LS route. Find a LS donor for engine transmission harness and PCM. There is lots of.information to perform swap.
Burning Brakes
Joined: Sep 2017
Posts: 929
Likes: 164
I would like to keep the crossfire, I think its an interesting system and I am trying to keep the motor stock. I am pretty certain though that I am going to have to do a swap. I was mostly wondering things about a swap, like do I need to worry about certain years for the 350 that wont be a direct bolt in replacement, or anything like that.
the big problem with getting more hp out of crossfire is the intake manifold. calculating from cross section area,
runner only flow 150 -159 cfm . cylinder head flow 196 cfm.
there's members on this forum that have ported there intakes. they would know how much material can be removed and where its safe.
my porting job was different because I was afraid of cutting into a water jacket. I built up the top of the intake port by adding weld and then raised the port a .25". took a long time. now outflow the head by just a little. can always weld it more if I get new heads.
some useful sites Xfire Performance XFire Performance Wallace Racing - Automotive Calculators
Burning Brakes
Joined: Sep 2017
Posts: 929
Likes: 164
That is another thing I was wondering, if I remove the smog pump and change the headers, would that have any gain in power or any benefits? I believe the previous owner, an older guy who got old and couldn't mess with it anymore already has put a true dual exhaust out the rear. He also swapped the 4+3 with a 6 speed.
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Pro
Joined: Aug 2020
Posts: 647
Likes: 126
From: Liliha Bakery stuffing my face with coco puffs!
That is another thing I was wondering, if I remove the smog pump and change the headers, would that have any gain in power or any benefits? I believe the previous owner, an older guy who got old and couldn't mess with it anymore already has put a true dual exhaust out the rear. He also swapped the 4+3 with a 6 speed.
Burning Brakes
Joined: Oct 2017
Posts: 823
Likes: 106
From: Somewhere near Fort Wayne, Indiana
I'm going to agree with Steve here, pull the motor and see what you have. I'm also going to say to pull the heads and inpsect the cylinders, then inpect the bottom end to see how usable the engine is.
Drifting
Joined: Mar 2006
Posts: 1,263
Likes: 188
From: Wabasha Mn
I would just go shopping for a crate engine either a 350 or 383 with aluminum heads. I would not waste time and money on originality. The CFI intake will require some porting to clean it up. The other choice is the LS route. Find a LS donor for engine transmission harness and PCM. There is lots of.information to perform swap.
1984 block has 2 pc rear main seal and flat top pistons. 1986 and older intake manifold bolt pattern is standard bolt pattern.1986 started having 1 pc rear main seal. different style crankshaft and flex plate for auto trans. newer motors could have dished pistons
the big problem with getting more hp out of crossfire is the intake manifold. calculating from cross section area,
runner only flow 150 -159 cfm . cylinder head flow 196 cfm.
there's members on this forum that have ported there intakes. they would know how much material can be removed and where its safe.
my porting job was different because I was afraid of cutting into a water jacket. I built up the top of the intake port by adding weld and then raised the port a .25". took a long time. now outflow the head by just a little. can always weld it more if I get new heads.
some useful sites Xfire Performance XFire Performance Wallace Racing - Automotive Calculators
the big problem with getting more hp out of crossfire is the intake manifold. calculating from cross section area,
runner only flow 150 -159 cfm . cylinder head flow 196 cfm.
there's members on this forum that have ported there intakes. they would know how much material can be removed and where its safe.
my porting job was different because I was afraid of cutting into a water jacket. I built up the top of the intake port by adding weld and then raised the port a .25". took a long time. now outflow the head by just a little. can always weld it more if I get new heads.
some useful sites Xfire Performance XFire Performance Wallace Racing - Automotive Calculators