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Discussion Starter #1
So I have a good running SBC 350 that's a good running engine but I love the idea of putting a LM7 into my 66 nova. I know Holley makes conversion kits and I can get adapter plates to mount up to my 700R4. I've seen plenty of low mileage LM7 engines for roughly around $1K on ebay and other suppliers. Before I dive into this can someone help me understand what all will be needed and why with a ball park $ by each item? I've been reading books on doing LS swaps but before I dive into this venture I'd like to understand if the $ make sense.

Much appreciated.
 

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I have done two swaps, one carb, one EFI, not as many as others, but I have learned a few lessons. I love the engines.
Driveline angles were my largest hurdle. The oil pan is low in the chassis on these engines and crossmember / steering clearance restricts ho low it can go. So the engine has to come forward from the stock SBC location, or on some chassis the trans tunnel may need some clearance, to get the transmission yoke at the correct ~ 3 deg angle.
A used base engine is usually the cheapest part of the swap, there are budget ways for everything, but that depends on your ability to modify parts. I tried to use as many stock parts as possible from the recycler, catalog parts add up fast.
Here is a basic list to get started, you did not specify carb or EFI? Adding $$ to this? there are so many options. I am probably forgetting some stuff
  • Engine mounts, make some or buy adapter plates
  • Oil pan. Do you have stock front end or aftermarket clip? LM7 truck pan is way too deep for a car, can be modified. There are lots of aftermarket options, steel & aluminum. Pick up tube to match the pan
  • Flex plate & torque converter. The stock LM7 is dished. Two options, get a specific torque with extended pilot, or get a flex plate and spacer from a 4L80E they are flat and your stock torque will bolt up
  • Cooling system & air bleed lines. The system is different then SBC. There are aftermarket rads for swaps, or you can get creative with hoses and fittings to make a stock rad fit.
  • Cooling fans. Electric is the most common option. The carb swap I did was in a 67 GMC, so I was able to use the stock truck fan. The EFI was in a 69 Chevelle, used Camaro fans.
  • Front drive brackets. Guys use the truck set up, but it is tall. Some aftermarket can get expensive fast
  • Starter, Alternator, water pump, power steering?
  • Carb or EFI? Stock manifold or aftermarket? Carb manifold.
  • Engine throttle connection
  • Throttle valve connection for your 700R4
  • Harness and electrical. EFI engine harness & PCM, programing of PCM if factory or aftermarket PCM (Terminator X?). Carb engine control box and harness. Interconnection to your factory harness
  • Fuel delivery system, you will need electric pump system carb or EFI
  • Exhaust, the truck manifolds will not fit a stock clip, there are header options to fit the narrow frame rails.
Hope this helps with your planning
 

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Using my list on my swaps,
69 Chevelle LM7, 5.3 $800 used engine, stock 350 hp EFI ~ $6000 (Including engine)
409512


67 GMC LQ9 6.0, $4000 GM exchange, Carb with cam upgrade, ~ 480HP, ~ $8800 (including engine)
409513
 

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Chvcraz, great advise and beautiful work.
Jes, I suggest watching "The Driveway Engineer" on youtube. He's an opinionated cheapskate that is to the point and educational. Also LT1swap.com. Read his (Brandon) site front to back. Between these two guys you will have a descent foundational knowledge and feel more confident as you get started.
 

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Discussion Starter #5
I have done two swaps, one carb, one EFI, not as many as others, but I have learned a few lessons. I love the engines.
Driveline angles were my largest hurdle. The oil pan is low in the chassis on these engines and crossmember / steering clearance restricts ho low it can go. So the engine has to come forward from the stock SBC location, or on some chassis the trans tunnel may need some clearance, to get the transmission yoke at the correct ~ 3 deg angle.
A used base engine is usually the cheapest part of the swap, there are budget ways for everything, but that depends on your ability to modify parts. I tried to use as many stock parts as possible from the recycler, catalog parts add up fast.
Here is a basic list to get started, you did not specify carb or EFI? Adding $$ to this? there are so many options. I am probably forgetting some stuff
  • Engine mounts, make some or buy adapter plates
  • Oil pan. Do you have stock front end or aftermarket clip? LM7 truck pan is way too deep for a car, can be modified. There are lots of aftermarket options, steel & aluminum. Pick up tube to match the pan
  • Flex plate & torque converter. The stock LM7 is dished. Two options, get a specific torque with extended pilot, or get a flex plate and spacer from a 4L80E they are flat and your stock torque will bolt up
  • Cooling system & air bleed lines. The system is different then SBC. There are aftermarket rads for swaps, or you can get creative with hoses and fittings to make a stock rad fit.
  • Cooling fans. Electric is the most common option. The carb swap I did was in a 67 GMC, so I was able to use the stock truck fan. The EFI was in a 69 Chevelle, used Camaro fans.
  • Front drive brackets. Guys use the truck set up, but it is tall. Some aftermarket can get expensive fast
  • Starter, Alternator, water pump, power steering?
  • Carb or EFI? Stock manifold or aftermarket? Carb manifold.
  • Engine throttle connection
  • Throttle valve connection for your 700R4
  • Harness and electrical. EFI engine harness & PCM, programing of PCM if factory or aftermarket PCM (Terminator X?). Carb engine control box and harness. Interconnection to your factory harness
  • Fuel delivery system, you will need electric pump system carb or EFI
  • Exhaust, the truck manifolds will not fit a stock clip, there are header options to fit the narrow frame rails.
Hope this helps with your planning
What is PCM mean and what does it do? My plan would be to stay with an EFI. If I stick with a the stock intake I'd have to send the wiring harness to be modified correct? I also read something about where I'd have to change out my fuel pedal as well.

Does the the trans yoke degree need to be exact if I'm using a 700R4?

Where's a good reputable engine supplier? I've seen a few in eBay but I'm not impressed with the reviews. What should I make sure comes with the engine?

Thank you for your help. It's greatly appreciated.
 

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If you can't find an engine locally you might try Casey Fodor in Ohio. He has a family wrecking yard and typically has several LS engines of all prices and is honest
Fodor Auto Parts.
He ships all over and has great rates on truck transport.
PCM= powertrain control module.
Read the LT1swap site. It with decode all the jargon
 

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Agreed Alf, LT1 swap is a great site, helped me so much to figure things out
With the modern stuff every part & system has abbreviations it seems, I get carried away typing

Jespinoza, I believe getting a engine from a yard is the best, get one that's been tested. From a yard you can request all the accessories, wiring & control modules that came with the engine (if your going for EFI).
LM7's were cable throttle till 2003 ish depending on the donor, then went drive by wire (DBW). DBW is more difficult in a sense that you must have the correct electronic (fuel) pedal, control module & throttle body to make it work, like I said get all the stuff from the same vehicle. The truck pedals are huge and will not go in the car without modification, I modified mine. Drive by cable is just that, find a cable & brackets that fits.
Yes the factory wiring will have to be modified, read LT1 site & stickies at the top of this page, it varies by year and vehicle type. If all that is too much there are companies listed in this site that make retrofit harnesses. The factory PCM will have to be reprogramed. Or you can also go with complete aftermarket control & harness systems.
Drive line angles should be kept within tolerance, regardless of the transmission, if not you can have vibration, noise and can damage your universal joints. 3 degrees is best, > 5 degrees can be noisy (personal experience haha).
Take your time, do some more specific reading, there are a few other threads & stickies in this site relating to your questions
 

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I would look for a cable throttle body engine, newer the better 2003+, only because you mentioned the 700R4 and you need a cable throttle valve connection for that transmission. Vans used cable up to 2007? I believe, trucks early 2004. Lokar and others make cables & adapters, may have to modify the bracket for the truck manifold. Now you could take any engine (24x) and make it a cable throttle, but if its a package, all the better as mentioned before.
If you found a 4L60E transmission and engine combo all the better, no cable needed for the electronic transmission haha. As I'm sure your seeing there are many combinations.
See what package is available and in your budget, then build your system around that.
Here is a shopping guide haha. Helps show what engines were in what vehicles.

The Definitive Guide to LS Engine Specs and LS Engine Upgrades
 

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This is good timing for me as well. I recently acquired a 6.0 and have been looking around the LSX forum but there is not a lot of current stuff happening in there.
 

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It is such an expensive undertaking that is why I am stuck with my SBC. I did some "back of the envelope" calculations last year and even if I got a great motor and trans free it was going to cost me north of $5k in Canada. With a crate motor and trans or rebuilding it was going to get close to $15k. Need to win the lottery and then going LS and Schwartz chassis. Good luck, I hope it works out for you, it is definitely the way to go with all the info out there now.
 

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I’m doing a swap right now in my 65 and here is my $0.02.

Absolutely stay with efi, it is a great system. Carb can work too, but I would stay with efi. Also, the junkyard is your friend. These engines are way overbuilt so you can find lots of used swap parts for a decent price.

If it was me, I would sell that transmission and get a 4l60e. The price difference shouldn’t be that much. CBR makes a swap transmission mount and you can custom tailer all the shift points electronically.

Engine:
-if you find an L33(5.3 w/aluminum block, good heads, 10:1 cr) get that. It’s worth some extra $$.
-depending on your power goals, a set of milled 243/799 heads would be a good investment for about $500
-Lm7 engines are cheap and plentiful
-Do an aftermarket cam swap. You can stick with stock rockers. This will make a huge power difference without costing driveability. If you go past a certain size, you will need a stall converter which is fine but an additional expense. In my opinion, swapping in another stock cam is a waste of time.
-CBR makes swap headers that are really nice.
- if you are using stock steering, a gto pan will work. If using aftermarket steering, an f body pan will work. Make sure you get the matching pickup and windage tray for each pan. Used is fine

Efi:
-I’m going with the Holley Terminator max x. Once you factor in that it comes with a harness, the cost seems better. If you get a swap with a complete harness and pcm, you can sell these to offset the cost.
- you can go with either a cable driven throttlebody (DBC)or an electronic one. Cable is easier and usually a bit cheaper. With DBW(drive by wire) you will need the matching pedal and a few other things. Setting up cruise control with dbw is easier but it can be done with either.

Cooling:
You can spend a lot or a little in this part. If you already have a good aluminum radiator, a nice electric fan setup should get it done. Otherwise, it can range from cheap($200 used f body fan/radiator) to expensive, but very nice(entropy). Adapting stock stuff will take a little fabrication but not too much.

Gauges:
You can either fan something up or get a Dakota digital or other aftermarket cluster. Electronic transmissions wont have a cable.

There are a bunch of vendors who make things easy for this swap. You can buy a whole fuel system with everything you need for under $500(CPP using a tanks inc fuel tank). Pypes makes a nice stainless exhaust for $450.

Obviously I think it’s worth it because I am doing the swap haha. A lot of the new parts like fuel system, exhaust or cooling are things you would probably have to upgrade eventually with any engine setup. The nice thing is that if you decide to upgrade down the road, it’s very easy. Find a deal on a 6.0 or 6.2? Swap it in and retune. That’s it. You will always have enough vacuum for power brakes with good tuning as well.

Ls1tech.com has a ton of great info as well

I hope this was helpful!
 

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1967 Chevy II nova Hardtop
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How much for the fuel system? How about how much to make all of your guages work including the speedo? How much were those headers? Did you change the cam? Now you need a tune. $500.00 around here. What you have there is an engine sitting in a frame. Having a driving vehicle with all systems working is more like Chevcraz has experienced.
 

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Having compared the specs for the LQ4 and LQ9 on the “On All Cylinders” pages. The LQ9 has slightly higher at 10.1:1 vs 9.4:1 for the LQ4. The only physical difference I can find in the specs listed to make this happen is LQ9 has flat top pistons and the LQ4 has dished. The block casting numbers, aluminum heads (317) , and cam are all the same. I know the engine came out of a 2500 Sierra but I don’t know the VIN numbers and I haven’t found a sticker or anything else to determine which one it is.. Are the pistons the only difference between the two designations.?
 

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Stock engine or cam swap; here is my experience
When I was planning the 5.3 EFI engine in the Chevelle everyone (magazines & internet) put a cam in it. After looking into it the $$ was adding up, and another $600 for a cam swap was something I questioned, do I really need to do this now?
My thinking was it will be enough effort to get this to run and drive. So many stories of tuner troubles, drivability issues with modified engines and someone's tune... So I decided I needed to educate myself on how to tune this engine stock before wading into the modified engine.
I have built and tuned many stock to wild SBC & BBC, but gen 3 electronic tuning was new. So I also budgeted HP Tuners into the build. Because I wanted to learn.
I have spent time on and off perfecting my tune of the stock engine. There are many good sources to learn from, but few are complete, lots of try this and that advice. I have it close now, my airflow data shows 340 HP (altitude corrected to sea level), car runs great, super responsive and quick (2000 stall Saturday night special torque, 3:55 gears on 26" tires), also gets 25 MPG.
So now I think I am ready for a cam, but I am going with a weenie stage 1, I don't want to loose the drivability, I have A/C & cruise control. The stage 1 cams will be ~ 400 HP, plenty for that car. Planning this winter to install one and back to tuning.
Now I know you can just take it to a Tuner $$, then back if it acts up $$.
My advice if you want to learn to tune & are working with the stock Control module, get HP Tuners and start learning tuning on the stock engine.
Now If you want to go aftermarket control they package that all together for you, but you will still have to learn to tune or pay someone $$.
 

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Are the pistons the only difference between the two designations.?
To my knowledge you are correct. Look through the plug hole to see if its flat tops or dish.
The other difference was the later LQ9's had floating piston pins, can't see that through the plug hole haha.
I have not researched on how to decipher any tags on the engines. I have read they do stamp the VIN so you could look for that and the 8th character to ID the engine?
 

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This guy is really helpful with LS modifications...

Chevycraz I had no idea you could benefit from tuning a stock LS engine. 25MPG!!
Good stuff!!
I have been dipping my toe in the tuning game and it scares me to death.....
 

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It’s not a cheap swap for sure but I believe it is worth it. I am going with Holley Terminator x max instead of hp tuners because there is some self-learning but the tuning is more intuitive. And when you figure he cost of hp tuners + wide band + harness, the cost is about the same.

Something to note is that engine prices can vary widely depending on your location. I’ve seen plenty of people getting lm7 engines for a couple of hundred bucks while I usually see them double or triple that.


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