Chevy Square Body Truck New Build - Need suggestions
08-20-2014, 02:59 PM
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Chevy Square Body Truck New Build - Need suggestions Hey Guys,
I am completely new to the LS world. I am preparing for an engine swap on my 84 Chevy K10 short bed pickup (along with new wiring, 1 ton axles, interior upgrades, etc etc). The truck currently has a mildly built 355 in it mated to an SM465 tranny. All of the research I keep doing points me back to this forum as it seems you guys know more than anyone else about these engines. I am completely open for suggestion. My main goals here are: reliability and fun to drive power. Not worried at all about fuel economy or cold weather drivability as this is only a summer toy for me.
I have a couple good leads on some used LQ9 engines with roughly 135k miles on them. For cost and complexity reasons, I have decided to go with a carb on the new LS that I choose. Because the truck is heavy and I plan on using it on the road and also at the sand dunes, I will need a set up with a lot of low end torque. Behind the LS, I will be going with a 700R4 tranny I already have built, 4.56 gears with lockers in both axles and a 205 gear to gear transfer case.
The truck is heavy; these are the last trucks from the era of when real steel was used for body panels.
The 1 ton axles, transfer case and suspension upgrades will add considerable weight to this build. But...I want the strongest drivetrain I can get for severe duty use especially during a weekend at the sand dunes.
I was really inspired by this article in my search of which engine to build.
http://www.carcraft.com/techarticles...s/viewall.html
This config seems right on par with what I want to spend but my concern is that I lose some torque down low, where a heavy truck needs it the most.
I am looking for ideas on how to get a torquier bottom end but still have some high RPM power for drags at the sand dunes and also light to light type driving
I am happy to provide whatever info I can about the truck or my plans. Here is a pic of her as well. Appreciate all of the help!
I am completely new to the LS world. I am preparing for an engine swap on my 84 Chevy K10 short bed pickup (along with new wiring, 1 ton axles, interior upgrades, etc etc). The truck currently has a mildly built 355 in it mated to an SM465 tranny. All of the research I keep doing points me back to this forum as it seems you guys know more than anyone else about these engines. I am completely open for suggestion. My main goals here are: reliability and fun to drive power. Not worried at all about fuel economy or cold weather drivability as this is only a summer toy for me.
I have a couple good leads on some used LQ9 engines with roughly 135k miles on them. For cost and complexity reasons, I have decided to go with a carb on the new LS that I choose. Because the truck is heavy and I plan on using it on the road and also at the sand dunes, I will need a set up with a lot of low end torque. Behind the LS, I will be going with a 700R4 tranny I already have built, 4.56 gears with lockers in both axles and a 205 gear to gear transfer case.
The truck is heavy; these are the last trucks from the era of when real steel was used for body panels.
The 1 ton axles, transfer case and suspension upgrades will add considerable weight to this build. But...I want the strongest drivetrain I can get for severe duty use especially during a weekend at the sand dunes. I was really inspired by this article in my search of which engine to build.
http://www.carcraft.com/techarticles...s/viewall.html
This config seems right on par with what I want to spend but my concern is that I lose some torque down low, where a heavy truck needs it the most.
I am looking for ideas on how to get a torquier bottom end but still have some high RPM power for drags at the sand dunes and also light to light type driving
I am happy to provide whatever info I can about the truck or my plans. Here is a pic of her as well. Appreciate all of the help!
08-20-2014, 06:32 PM
#3
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wow ... sound like you want some of everything.
I'd stay with factory intake and EFI. Perhaps consider a turbo or supercharger, but keep low rpm cam and stock heads and bottom end. Spend your money on the forced induction and exhaust and plumbing.
I've heard 4L80 is the way to go vs. 700R4. I run the 6L80 (6 speed). Perhaps even consider a 6L90. The extra gears might really be useful in what you are doing. 1st is very low.
Interesting crossroads. Will be curious how this plays out.
Doug
I'd stay with factory intake and EFI. Perhaps consider a turbo or supercharger, but keep low rpm cam and stock heads and bottom end. Spend your money on the forced induction and exhaust and plumbing.
I've heard 4L80 is the way to go vs. 700R4. I run the 6L80 (6 speed). Perhaps even consider a 6L90. The extra gears might really be useful in what you are doing. 1st is very low.
Interesting crossroads. Will be curious how this plays out.
Doug
08-20-2014, 11:53 PM
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First off, welcome aboard!!! That looks like a pretty cool truck you've got there!
Meh. If you're familiar with a carburetor and/or scared of EFI, OK, but I certainly wouldn't go with a carb due to cost reasons - in terms of prices, they tend to be pretty even...
DANGER Will Robinson, DANGER!! 
Seriously - we have people on this board who have repeatedly fragged their 700R4s while driving MUCH lighter vehicles than yours!!
If the 700R4 is something that you're using until you can get a 4L80E (or better), that's great - but in all honesty, I wouldn't count on getting a lot of life out of that transmission in that vehicle, unless you drive like great-grandma in the church parking lot...
(Whether it's "built" or not...)
Yeah, you & me both - if you look at the first few posts of my build thread, you'll see a link to that article there as well...
One word - CUBES. The more cubic inches you can muster, the better that a HEAVY vehicle like that is going to perform (of course you can apply boost to a stock engine as well, but that tends to be more expensive). One of the best compromises these days is to get an iron-block 6.0L & add a stroker crank to it, which generally gives you about 408 cubic inches. That's kind of a "sweet spot" between reasonable cost & good power.
Probably the best suggestion that I can offer you is to do a lot of reading here - start with the "stickies" at the top of this forum, maybe run through the "lessons learned" thread, and then any/all other threads that catch your interest. (I've picked up little tidbits of info from threads that I've thought would have NO relevance to my swap, so keep your eyes open!)
One last thought - while I'm on this board, I keep a file open, so that when I find one of those "tidbits", I can copy it into that file, & don't have to wonder "Where did I see that again?" (I actually got the URL for the "lessons learned" thread from that file.)
Good luck!
Seriously - we have people on this board who have repeatedly fragged their 700R4s while driving MUCH lighter vehicles than yours!!
If the 700R4 is something that you're using until you can get a 4L80E (or better), that's great - but in all honesty, I wouldn't count on getting a lot of life out of that transmission in that vehicle, unless you drive like great-grandma in the church parking lot...
(Whether it's "built" or not...)Probably the best suggestion that I can offer you is to do a lot of reading here - start with the "stickies" at the top of this forum, maybe run through the "lessons learned" thread, and then any/all other threads that catch your interest. (I've picked up little tidbits of info from threads that I've thought would have NO relevance to my swap, so keep your eyes open!)
One last thought - while I'm on this board, I keep a file open, so that when I find one of those "tidbits", I can copy it into that file, & don't have to wonder "Where did I see that again?" (I actually got the URL for the "lessons learned" thread from that file.)
Good luck!
08-21-2014, 04:13 AM
#5
Thats a damn nice looking truck! I agree with the others, I would stay EFI. Carb conversions are the same as far as cost goes, and theres no reason to be intimidated by it. You could get an '87 gas tank, since the trucks were fuel injected that year they have baffled tanks, and swap in a higher pressure pump and then run a few lines and the fuel system would be done.
As for power, a 6.0 should do the trick, but if you have the funds, a 6.2 would really wake the truck up.
Also, as the others have said, if you are going to be putting down some power, a 4l80e would be a better option. If you keep it fuel injected, you could get an instrument cluster out of a 88-90 blazer or burb and use the electric speedo since the newer transmission s dont have speedo cables.
What ever you decide to do, best of luck with it, and keep us updated.
As for power, a 6.0 should do the trick, but if you have the funds, a 6.2 would really wake the truck up.
Also, as the others have said, if you are going to be putting down some power, a 4l80e would be a better option. If you keep it fuel injected, you could get an instrument cluster out of a 88-90 blazer or burb and use the electric speedo since the newer transmission s dont have speedo cables.
What ever you decide to do, best of luck with it, and keep us updated.
08-21-2014, 07:48 AM
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Thanks for all of the input everyone. Looks like keeping the FI might be the way to go. I already have a bunch of money into this 700R4 so for now, I will be running that. I know that's against everyone's suggestion at this point, but I already have a lot of money into it. And this was supposed to be a "budget" build. LOL So with extra coolers and some internal upgrades I guess we will see how long she lasts. I have looked at the 4L80 and 6L80/90 trannys as well, the problem becomes the length of the tranny because its a short bed truck. Between the big steel 205 gear to gear transfer case and long tranny, the driveshafts get really short with steep angles because of the lift. Not saying it cant be done but that was an initial point of concern of why I didn't go that route in the first place.
Again, coming new to the LS world and new to ever changing a carb vehicle to EFI, I am intrigued and confused about how this would work. If I get this LQ9 and do some upgrades on it, how do I get it to run? I was always under the impression that these motors couldn't be stand alone and I don't know anyone who can do LS/EFI tuning in my area. Also, with a cam and head upgrades, for example, are the stock injectors and ECU going to be able to handle these changes?
With regards to the 408 kits, I had looked at a few engines already built that are turn key. Texas Speed and Performance has a pretty sweet 408 with EFI already ready to go. Price is a big concern on something like that though (pretty much double from what I calculated). But they look like some bad*ss motors and heard a lot of good things about them. Does anyone make a good quality turn key LS set up that I can just drop in and not spend $15k for?
Not trying to be "cheap" at all on this build but I already have a TON invested in the axles, lockers, suspension, etc. and I find myself always wanting the best hard parts and pieces I can get. (I have over $3k in just a front Dana60 axle!).
Again, coming new to the LS world and new to ever changing a carb vehicle to EFI, I am intrigued and confused about how this would work. If I get this LQ9 and do some upgrades on it, how do I get it to run? I was always under the impression that these motors couldn't be stand alone and I don't know anyone who can do LS/EFI tuning in my area. Also, with a cam and head upgrades, for example, are the stock injectors and ECU going to be able to handle these changes?
With regards to the 408 kits, I had looked at a few engines already built that are turn key. Texas Speed and Performance has a pretty sweet 408 with EFI already ready to go. Price is a big concern on something like that though (pretty much double from what I calculated). But they look like some bad*ss motors and heard a lot of good things about them. Does anyone make a good quality turn key LS set up that I can just drop in and not spend $15k for?
Not trying to be "cheap" at all on this build but I already have a TON invested in the axles, lockers, suspension, etc. and I find myself always wanting the best hard parts and pieces I can get. (I have over $3k in just a front Dana60 axle!).
08-21-2014, 08:04 AM
#7
These engines can absolutely be stand alone, there are about a thousand threads on this site that prove that! Lol!
If you are dead set on keeping the 700r4, then I would look for a DBC enginesince the TV cable is a must with them and its easier to hook to a cable throttle body than a DBW one.
Do a search on here and you will find a lot of people who can mod harnesses, if you dont want to do it yourself, although it isnt all that hard, and a lot of people who can tune your PCM for your application. You didnt say where you are at, but id be willing to bet that there is someone in your area that can do a tune, theres just so many people who can do that these days.
If you are dead set on keeping the 700r4, then I would look for a DBC enginesince the TV cable is a must with them and its easier to hook to a cable throttle body than a DBW one.
Do a search on here and you will find a lot of people who can mod harnesses, if you dont want to do it yourself, although it isnt all that hard, and a lot of people who can tune your PCM for your application. You didnt say where you are at, but id be willing to bet that there is someone in your area that can do a tune, theres just so many people who can do that these days.
