1988 305 -> 1996 Vortec L31 350. What do I need to know?
Thread Starter
Member
Joined: Aug 2009
Posts: 332
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From: AZ
Car: 1978 Chevrolet impala
Engine: 350ci 300hp/356tq pace crate
Transmission: 700r4
Axle/Gears: 3.42 Yukon posi
1988 305 -> 1996 Vortec L31 350. What do I need to know?
Okay so I'm looking to get the rundown on what I'll be looking for while doing this swap. Most of the stickies are on more radical swap concepts, and while mine is pretty basic I'm just looking for pointers as to what I should be doing.
It's a 1988 Formula with the W/C T5 behind a leaking clicking 180k 305. I'll keep the stock tranny for this, and rebuild it with stronger guts later should it explode. 5th gear grabs a little shifting but I'm not sure whether or not this is normal old-car chatter or if that means my syncros are going.
The motor is already carb swapped, and I know I need the standard oil filter adapter to replace the cooler fitting that will get in the way of my headers. I have an Air Gap manifold picked out (clearance issues?) and poly mounts waiting for install. I intend to replace the clutch disc/pressure plate (unless that's a bad idea?) when I swap the motor.
To sum it up I'm trying to keep this as dead cheap as possible, and protect my ancient tranny. As such I wont be upgrading the engine's internals (255 HP with a good manifold and exhaust should be more than enough car for me anyway). What do I need to look for? How should I go about pulling it? Putting it back in? Anything to be careful of? Should I pull the tranny out too or is it fine as is? I know NOTHING about transmissions and breaking something would be a nightmare for me.
What should I know about lining everything up? If I pull the transmission, what needs to be disconnected and how do i go about it without bungling it horribly? If I leave it where it is (preferred!) What is the safest, simplest method of unbolting it? Any advice on getting this swap done quick?
Thanks a ton in advance!
J
It's a 1988 Formula with the W/C T5 behind a leaking clicking 180k 305. I'll keep the stock tranny for this, and rebuild it with stronger guts later should it explode. 5th gear grabs a little shifting but I'm not sure whether or not this is normal old-car chatter or if that means my syncros are going.
The motor is already carb swapped, and I know I need the standard oil filter adapter to replace the cooler fitting that will get in the way of my headers. I have an Air Gap manifold picked out (clearance issues?) and poly mounts waiting for install. I intend to replace the clutch disc/pressure plate (unless that's a bad idea?) when I swap the motor.
To sum it up I'm trying to keep this as dead cheap as possible, and protect my ancient tranny. As such I wont be upgrading the engine's internals (255 HP with a good manifold and exhaust should be more than enough car for me anyway). What do I need to look for? How should I go about pulling it? Putting it back in? Anything to be careful of? Should I pull the tranny out too or is it fine as is? I know NOTHING about transmissions and breaking something would be a nightmare for me.
What should I know about lining everything up? If I pull the transmission, what needs to be disconnected and how do i go about it without bungling it horribly? If I leave it where it is (preferred!) What is the safest, simplest method of unbolting it? Any advice on getting this swap done quick?
Thanks a ton in advance!
J
Senior Member
Joined: Nov 2009
Posts: 419
Likes: 1
Car: 1986 Trans Am
Engine: 5.0
Transmission: 700r4
Axle/Gears: beats me
Re: 1988 305 -> 1996 Vortec L31 350. What do I need to know?
We are both riding in the same boat. I found a '96 camaro being parted out and I am thinking of a swap. My 305 is puffing out the blue smoke and my trans fluid gets dark after 6 months of driving. So I may as well swap out both.
As I sit here waiting at the dock for my truck to be unloaded, i am searching the various stickies and post. I hope umbrella seals will help the smoking(idle and cruising) But I don't expect it to get better.
I keep staring at my 500 Cadillac/4l80e combo and wondering "hmmmmmmm"
As I sit here waiting at the dock for my truck to be unloaded, i am searching the various stickies and post. I hope umbrella seals will help the smoking(idle and cruising) But I don't expect it to get better.
I keep staring at my 500 Cadillac/4l80e combo and wondering "hmmmmmmm"
Joined: Mar 2000
Posts: 43,187
Likes: 45
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
I hope the Air Gap intake you're looking at is Vortec style.
Personally, I would pull and install the engine and transmission together. Lining up the input shaft/pilot bearing/clutch disk is a lot easier when you aren't on you back in cramped spaces. Drain the tranny, remove anything attached to it that doesn't go to the engine.
I believe you either need to, or should, remove the front cover. There are cam/crank sensor things that can be removed, and will allow the use of a "standard" front cover and damper.
Your flywheel should fit the L31. Make sure to install a new pilot bushing or bearing.
Personally, I would pull and install the engine and transmission together. Lining up the input shaft/pilot bearing/clutch disk is a lot easier when you aren't on you back in cramped spaces. Drain the tranny, remove anything attached to it that doesn't go to the engine.
I believe you either need to, or should, remove the front cover. There are cam/crank sensor things that can be removed, and will allow the use of a "standard" front cover and damper.
Your flywheel should fit the L31. Make sure to install a new pilot bushing or bearing.
Thread Starter
Member
Joined: Aug 2009
Posts: 332
Likes: 0
From: AZ
Car: 1978 Chevrolet impala
Engine: 350ci 300hp/356tq pace crate
Transmission: 700r4
Axle/Gears: 3.42 Yukon posi
Re: 1988 305 -> 1996 Vortec L31 350. What do I need to know?
the timing cover you mean? What all needs to be removed and how will it affect it if I dont?
EDIT: Does this mean I will need a different harmonic damper?
EDIT: Does this mean I will need a different harmonic damper?
Supreme Member
Joined: Dec 2005
Posts: 1,244
Likes: 1
From: Texas City, Texas Area
Car: 89 RS, 92 Z28
Engine: 305 TBI, 350 TPI
Transmission: 700R4 Both Cars
Axle/Gears: 3.23 Posi.. 4 wheel disc both cars
Re: 1988 305 -> 1996 Vortec L31 350. What do I need to know?
Yes, please tell more.....In the same boat..Except with Automatic...Want to do the Vortec in place of LO3...Cheap, and easy....Thanks for starting this thread, and thanks for the replys...Tom
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