1973 LS1 conversion
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
1973 LS1 conversion
I have a 73 coupe with an automatic transmission.
I am looking to do an LS1 swap with a 4L60E.
I have been told that a 5.3 LSX is an easier swap and everything fits better.
Does anyone have any advice? I found a motor and tranny for $1800. I know it's a lower HP motor, but seems considerably cheaper. Thanks for any help.
I am looking to do an LS1 swap with a 4L60E.
I have been told that a 5.3 LSX is an easier swap and everything fits better.
Does anyone have any advice? I found a motor and tranny for $1800. I know it's a lower HP motor, but seems considerably cheaper. Thanks for any help.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
I have a 73 coupe with an automatic transmission.
I am looking to do an LS1 swap with a 4L60E.
I have been told that a 5.3 LSX is an easier swap and everything fits better.
Does anyone have any advice? I found a motor and tranny for $1800. I know it's a lower HP motor, but seems considerably cheaper. Thanks for any help.
I am looking to do an LS1 swap with a 4L60E.
I have been told that a 5.3 LSX is an easier swap and everything fits better.
Does anyone have any advice? I found a motor and tranny for $1800. I know it's a lower HP motor, but seems considerably cheaper. Thanks for any help.
I haven't followed prices for a while but $1,800 for a motor and trans sounds pretty reasonable.
Rick B.
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
If you can get a complete LS1 out of an f-body you'll save lots of time, and possibly money. If you get a 5.3L engine, you'll be looking for lots of parts off of an f-body LS1 engine. I have a 5.3 LM7 that I'm looking to either drop in either in the Vette or on the camaro. I just picked up the f-body accessory brackets today off of ebay. A forum member recommended the book "How to Swap GM LS-Series Engines into Almost Anything" to me and it's been very helpful. You should pick this book up if you're really planning on doing the swap
. Good luck.
. Good luck.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
I'm using the book Jordan mentioned as a reference. It looks like that is the LM7 engine. The AC compressor most likely woudn't fit since it's in about the same position as the LS1 compressor - and that doesn't fit. The intake manifold looks like to will be too tall for the stock hood, and if you change to a LS1 manifold I wonder if the alternator will be in the way. I think that is what Jordan is talking about with the need for LS1 accessories and intake. If the engine has the electronic throttle control you will have to get a throttle pedal assembly also.
Who told you this was going to be easy?
Rick B
Who told you this was going to be easy?
Rick B
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
I'm using the book Jordan mentioned as a reference. It looks like that is the LM7 engine. The AC compressor most likely woudn't fit since it's in about the same position as the LS1 compressor - and that doesn't fit. The intake manifold looks like to will be too tall for the stock hood, and if you change to a LS1 manifold I wonder if the alternator will be in the way. I think that is what Jordan is talking about with the need for LS1 accessories and intake. If the engine has the electronic throttle control you will have to get a throttle pedal assembly also.
Who told you this was going to be easy?
Rick B
Who told you this was going to be easy?
Rick B
. You won't be able to use the accessories off of the truck. There's an idler almost in the top middle of the engine that won't allow him to use an LS1/6 intake. You're better off going with the f-body accessories. This is why it would be easier to look for a complete f-body LS1 engine. If you don't, you'll need the intake, fuel rail/injectors, belt system,etc... off of the LS1. You should really get that book. There's lots of great info on there. It evens shows you how to modify the wire harness.
Pro
Joined: Nov 2004
Posts: 667
Likes: 87
From: Bismarck IL.
I have a 73 with a 2002 LS1 and a 4l60 trans.I used the f body accessories and a custom ac bracket.Everything worked out great. The engine and trans has been about 3 years.I have put 3400 miles on my vette this year already. The vette is a blast to drive.
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Race Director
Joined: Dec 2007
Posts: 14,345
Likes: 4
From: Hartselle AL
St. Jude Donor '09
Here is a good article regarding the 5.3 vs 5.7 from a budget and practical perspective.
http://www.yatesefi.com/lsx-swap-guide.html
http://www.yatesefi.com/lsx-swap-guide.html
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I put a 6.0 LQ9 (same block as the 5.3) in my 68. Prices of the 6.0 LQ4 and LQ9 were about the same as the 5.3 iron blocks. Get the bigger engine, no one ever wished for a smaller engine in their vette.
The accessories and intake would not fit under my hood. You can swap out the intake for an LS1 (about $35) and use the truck injectors/rails or go with LS1 injectors/rail/wiring pigtails.
None of the accessories will fit. I made my own brackets but Kwik Performanve makes brackets that will fit the truck spacing.
I went with a mechanical fan/pulley on an LS1 water pump, but the easiest solution is to use an LS1 pump on spacers (ebay) to fit the truck spacing.
The accessories and intake would not fit under my hood. You can swap out the intake for an LS1 (about $35) and use the truck injectors/rails or go with LS1 injectors/rail/wiring pigtails.
None of the accessories will fit. I made my own brackets but Kwik Performanve makes brackets that will fit the truck spacing.
I went with a mechanical fan/pulley on an LS1 water pump, but the easiest solution is to use an LS1 pump on spacers (ebay) to fit the truck spacing.
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
I don't know about the prices of the LQ4/9 being almost the same as the 5.3 engines. I got my 5.3 for $200 and have seen LQ engines in the thousand+ dollar range. You really cant underestimate these small 5.3, they can handle lots of power. Go over to the ls1tech forum and search for info on these 5.3's. There are guys over there running these engines with a completely stock bottom end and turbo making 600HP
(ON A STOCK BOTTOM END!!!!). They do switch to 317 heads to lower the compression ration on the engine and run 15# of boost.
(ON A STOCK BOTTOM END!!!!). They do switch to 317 heads to lower the compression ration on the engine and run 15# of boost.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
Yeah, I know what you mean about the 5.3s. I'm actually planning on using one in my next swap (not a corvette).
Prices for not too high milage motors around here are $650-850 for the 5.3s and 950-1200 for the 6.0s. That price difference was a non-issue when I was buying a Richmond 6 speed, Vintage Air conditioning, new wiring harness, etc.
I'll be honest, I went with the 6.0 because the bigger bore was needed for the L92 head upgrade. But after doing the swap, I realized I was already overpowering the skinny 7" wide wheel/tires on my 68. So right now, no plans for any upgrades.
Prices for not too high milage motors around here are $650-850 for the 5.3s and 950-1200 for the 6.0s. That price difference was a non-issue when I was buying a Richmond 6 speed, Vintage Air conditioning, new wiring harness, etc.
I'll be honest, I went with the 6.0 because the bigger bore was needed for the L92 head upgrade. But after doing the swap, I realized I was already overpowering the skinny 7" wide wheel/tires on my 68. So right now, no plans for any upgrades.
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
I can't wait to get everything I need to drop the LM7 into my '78 Z28. I was thinking about dropping it in the Vette, but I think I want an aluminum block LSX for that one. Plus, I want to add turbo
and there's plenty of room for that in the Camaro.
and there's plenty of room for that in the Camaro.
