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New motor for 91 Blazer

dmagas

dmagas

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Hi all,
I live in Colorado and have talked to several performance shops and motor heads, can not get a straight answer at all. I have a 91 Blazer 4x4 stock 350 with headers and 456 gears. All I really want to do is get a brand new motor crate with transmission, now I am not sure with this combo would it work with my current transfer case. In addition being that it would be a newer computer and harness would you have to go to electronic gauges? I know GM has a performance site where to order new motor trans combo. Does anyone know what would be the best fit for a daily driver and yet go to the hills when wanting to. Any help if anyone has run into this situation of bringing an older vehicle to life with a new motor trans combo. Any help is appreciated.
 
Why not rebuild your motor and tranny?
Or new TBI ready crate, rebuild your tranny

Also, what part of CO?
 
bent72 said:
Why not rebuild your motor and tranny?
Or new TBI ready crate, rebuild your tranny

Also, what part of CO?
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North of Denver, i had a friend that I can not get a hold of that did something similar with a 2004 motor trans and it ran incredible exactly how I would like mine to run.
 
dmagas said:
North of Denver, i had a friend that I can not get a hold of that did something similar with a 2004 motor trans and it ran incredible exactly how I would like mine to run.
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I like the independent fuel injection system.
 
WHAT engine/trans combo are you talking about? Of course a newly rebuilt tbi 350 and 4L60 will bolt up to your current transfer case, it's what you have in the vehicle now.
 
It can be done. The '90 and '91 are easy in one aspect since they already have VSS in the transfer case.

@azblazer did a 6.0 / 4l80e on his '90.

You already have an electronic speedometer and the other gauges can be reused by moving the senders to the new engine.
 
Go new gm crate motor, and have your trans rebuilt at a good shop. No real reason to go new on that.
 
KILLER! might as well go with a GEN1 smallblock, It would be the easiest to install. This particular crate engine is pretty expensive...... could buy an LS........
 
MEANSTREAK K30 said:
KILLER! might as well go with a GEN1 smallblock, It would be the easiest to install. This particular crate engine is pretty expensive...... could buy an LS........
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So would LS be the way to go, independent fuel injection also shut off unneeded I am just not familiar and I want to do it right and once. I just wish I knew more about these engine swap I know there are many different ways to do it. I just want a new motor trans make sure it works with my transfer case all in harmony and basically have a new truck well at least the guts.....
 
I would just go with the gen 1 that came with your truck for simplicities sake.You don't need all that MPFI, unless you don't like how the stock TBI has worked for you. LS is a better engine (?), and people are swapping them in more and more , like rjfguitar above.I have not done an LS swap , so I have little more to add except that the LS swap might be more expensive. Someone else will probably break it down for you.
 
dmagas said:
So would LS be the way to go, independent fuel injection also shut off unneeded I am just not familiar and I want to do it right and once. I just wish I knew more about these engine swap I know there are many different ways to do it. I just want a new motor trans make sure it works with my transfer case all in harmony and basically have a new truck well at least the guts.....
Click to expand...

LS is the hands down choice it is a more efficient design. The gen 1 has nothing on it. I haven't followed the LS-swaps, but you've been given links where others have done it. It will take more effort to install the LS, but in the end, it will be worth it.
 
dyeager535 said:
LS is the hands down choice it is a more efficient design. The gen 1 has nothing on it. I haven't followed the LS-swaps, but you've been given links where others have done it. It will take more effort to install the LS, but in the end, it will be worth it.
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I have no doubt that the LS is a better design with it's deep skirt block , 6 bolt main,cathedral port cylinder heads, ect. The current record at Bonneville is George Poteet and his gen 1 small block built by a Ken Duttweiler(I know that Bonneville is a far cry from what we are talking about here),Makes you wonder why they did not use an LS engine if it is so much better a design?(fastest piston driven vehicle on land)
 
MEANSTREAK K30 said:
I have no doubt that the LS is a better design with it's deep skirt block , 6 bolt main,cathedral port cylinder heads, ect. The current record at Bonneville is George Poteet and his gen 1 small block built by a Ken Duttweiler(I know that Bonneville is a far cry from what we are talking about here),Makes you wonder why they did not use an LS engine if it is so much better a design?(fastest piston driven vehicle on land)
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My suspicion would be familiarity, cost and availability of parts. FWIW on his engine I see non-standard SBC heads, coil on plug, EFI, and an aftermarket block, so it's not like he took a gen1 motor and threw on a couple thousand dollars in parts and set the record.

I'm not into land speed record stuff, but in the circle track class I follow, Gen1's are used exclusively. Demand is driving lower pricing. I expect it will be within my lifetime that gen1 motors are not the predominant engine even in hobby racing classes.

These guys go into the benefits of the LS-design pretty well:L http://www.superchevy.com/news/1601-what-makes-the-ls-engines-so-great/
 
I have a L31 5.7 liter Vortec replacement crate motor I bought yyyeeeeaaaarrrrrrrrrrssssssssssssssssss ago. When my motor finally dies (86 gen 1) it'll be going in with a TPI unit I've been collecting parts for. If I didn't already have this motor I would go LS.
 
To the OP, dude if you are not familiar with motor swaps, I wouldn't do anything else other than a GM replacement TBI350 to replace yours and drop your tranny off at a shop to have them rebuild it (and beef it up too if you wanted). Simple, probably cheaper in the long run, and all you have to do is unplug sensors off old motor, and plug onto new motor.

LS swaps have a lot more involved in them then what anyone anticipates. They are bitchen (I'm swapping an 8.1 liter into a 89 crew cab right now....even though technically the 8.1 isn't an LS(we are splitting hairs here) the concept is the same when it comes to wiring) but like I said, if you haven't done anything like it before, just keep it simple, IMHO
 
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Yep, if you don't know what you're doing, just forget trying to tackle a big project. The all and powerful internet will tell you that everyone in the world is doing LS swaps and they just "bolt in" like nothing, you can do your LS swap on your lunch break.

It's not simple, it's complicated at times and if you don't have the mechanical skill and shop equipment to do it, the end result will not turn out well. Is it completely difficult and only for total experts? No, there are just a LOT of small steps to an LS swap.
 
I agree with these guys above, and I'll explain a bit more from my experience. You can spend as much time and money on whatever engine/tranny combination you want. If you're looking for a quick fix then I'd stick to a 1 for 1 crate engine swap from Summit Racing (or the likes). If you're looking to spend more time, money, and patience, then look for a gently used LS engine from a salvage yard. You can either edit the wire harness (remove unneeded wires) or you can pay $150-$300 for someone else (found on Internet) to professionally edit the harness (and re-loom it). Of course most people are quick to NOT mention all the complications involved with an LS swap like the following: conversion motor mounts, narrow headers to clear frame rails, modifying your throttle cable (drive by wire/drive by cable (know the difference)), fuel delivery & return (LS requires high pressure hoses & pump (Corvette style electric fuel pump)), wiring in the LS sensors to your dash gauges (oil pressure and temp), do you plan on using a AC compressor?? (LS compressor won't fit in stock location (hits K5 frame rail-need to relocate)), and we haven't even mentioned transmission compatibility or potential drive shaft length differences yet. Depending on the tranny, you'll either need a different flex plate to mate to a 700R4 or you can stick with the 4L60E (whichever version you choose).

I've installed a 5.3 LS in my '86 K5, and I can say it's a lot more complicated than most people will admit too. Looking back, I'm glad I did mine, but I could debate both sides to just sticking to a "new" 350 crate engine. I'll gladly share my website urls with you if you'd like more information about the swap. Keep in mind that everyone you talk to will likely tell you their own opinion based on their own experience (mine being no different). Ultimately you can find all the swap info you need, but you need to think about how much time, money, and patience you want to put into it.

My build thread...
https://ck5.com/forums/threads/project-p-dub-1986-k5-blazer-modifications-and-upgrades.317811/
 
I WOULD get a 383 Vortec EFI if I was gonna buy a crate motor. Why waste money on a 350? My 383 gets better gas milage than my 327 I was running and way more power.
 
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