Carb on LS Based motor

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ChevyRealHeavy

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Still in search of a motor for my crew cab from my last thread, was wondering if going Fred Flinstone with a newer motor is really that bad. I don't see much drawbacks. I'm trying to avoid wiring and replacing my fuel pumps again since I've already replaced everything that deals with fuel. before. What are your guys thoughts on putting a carb on something like a LQ4?
 

OkieFishMan

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Wouldn't bother me one bit. EFI is nice, but carbs will make just as much power, at the cost of a little bit of mileage. You can grab a good condition junkyard LS, do a few mods, swap it in, and end up with a great power plant for a reasonable cost. I say if that's what you want to do, go for it.
 

1987 GMC Jimmy

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Don't want to sound like a dummy to the LS guys running OBD II, but this is the only way I'd do an LS swap. That and a distributor kit. You get the modern, powerful motor without all the electronic baggage. If you set up a nice Quadrajet on it, I'd even go as far to say that mileage decrease would be negligible. That's a 750/800 CFM carb that will make it scream racing a teenager or excel pulling a load, but it's an economical design (small primaries, etc.) that'll make it feasible for more down to earth, everyday needs.
 

Camar068

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You could always keep an eye out for the Ignition stuff you need for the swap on craigslist to get it cheaper. Then when you buy your motor, get it complete with harness and all. Do your carb swap, and think about doing the EFI bit later. If not, sell that stuff to recoup some of your money.
 

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Appreciate the opinions, some other forums I was looking at were like EFI or die.
 

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I think I'd be going Q-jet on my 383 build that I'm doing now if it weren't for the 4L80e tranny. I want to keep factory computer and everything intact for that. FI Will create some challenges for sure.

I've never looked into it - are there good manifold options for LS to carb? What about distributor? I just googled it and the conversion kits look pretty pricey.....
 

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Still in search of a motor for my crew cab from my last thread, was wondering if going Fred Flinstone with a newer motor is really that bad. I don't see much drawbacks. I'm trying to avoid wiring and replacing my fuel pumps again since I've already replaced everything that deals with fuel. before. What are your guys thoughts on putting a carb on something like a LQ4?

Haven't seen a distributor for a LSX engine, so you would need to buy the the ignition box to make the cols fire, guessing it operates off the crank and cam sensors. Then cost of intake and carb if you dont have one. If this is the route you wnat to go find an deal withthe ecm and harness, you can usually sell them to recoupe some of the cost. A friend sold his harness and ecm for $200.
 

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Can't find them now, but I swear there was cheap LS intakes on ebay 2 years back for the conversion for around $120. Even read a few reviews on them and didn't hear any complaints.

so now....

-intake Holley $250
-ignition MSD $375 (comes with harness you connect to existing)
-Carb $300 (take your pick based on preference, $300 is w/o military discounts if that may apply)....most have one running on their engine now
-engine mounts Dirty Dingo $100
-cooling (cost depends on how elaborate you go)
-electric fuel pump $50
-relays for cooling and pump $100

What other expenses is there? Your going to have some other misc. stuff that is dependant on how far you tear into the engine, what you have laying around, what's on the vehicle now (exhaust and such) and how "perfect" you want the install to be.
 
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4WDKC

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Can't find them now, but I swear there was cheap LS intakes on ebay 2 years back for the conversion for around $120. Even read a few reviews on them and didn't hear any complaints.

so now....

-intake Holley $250
-ignition MSD $375 (comes with harness you connect to existing)
-Carb $300 (take your pick based on preference, $300 is w/o military discounts if that may apply)....most have one running on their engine now
-engine mounts Dirty Dingo $100
-cooling (cost depends on how elaborate you go)
-electric fuel pump $50
-relays for cooling and pump $100

What other expenses is there? Your going to have some other misc. stuff that is dependant on how far you tear into the engine, what you have laying around, what's on the vehicle now (exhaust and such) and how "perfect" you want the install to be.

regulator
possible headers if he cant get manifolds with it
adapter for flexplate.
 

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I'ma keep my mouth shut on this one, lol.
 

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IMO a computer ans miles of wires and hundreds of $$ on sensors only gives just a hair better performance than a properly tuned carbed engine.
OK, injectors and computer give you a cold running engine that a carb will have a hard time competing with. And fuel savings...? Well that's subjective on your driving habits and engine tune.
As consumers we are addicted to bling, and BS. It's not like everything that is 5 minutes old becomes obsolete. Sometimes new is better, but not across the board, no way.
How many of today's new trucks... $80K +..... will be on the road in 35 years like our beloved square bodies?
 

crazy4offroad

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I may be wrong but I don't think the lifter valley on LS engines has a place made for a distributor to meet a cam gear. It would require machine work which would be much more expense. I would just use the crank trigger. I can see the benefits of either setup, carb vs efi, but if you can get a complete engine with computer and harness for just as good of a deal as any, I would learn how to use the computer-controlled setup. Those easy cold starts, and if you drive with your heel you might be able to pull down 18mpg, it would be worth it IMO.
 

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