To Swap or not to swap that is the question.

[sreidmx]

So I am debating swapping an ls1 into my K5, I am not 100% convinced mainly because the engine in my truck has very low mileage. less than 25k. it runs pretty dang good.. I know the pros and cons, I am worried about the hidden costs.. its not just 800 bucks to swap it.. its more like 1500 if I account for the little stuff.. has anyone got insight into the swap? going from a good sbc to a used possibly higher mileage ls?

 

[Greg Ducato]

If you have a good running engine, I would leave it be and enjoy it vs a swap to an unknown used LS engine. Seems like kind of a waste to me

 

[sreidmx]

I agree, most of my collegues say spending a dime on this is a waste and I should ditch it in favor of new tech.. I think a few bucks on a dizzy and tbi and the other odds and ends for cheap would get me what I want.. megasquirt is cheap and I have the skills to make it work..

 

[dhcomp]

So I am debating swapping an ls1 into my K5, I am not 100% convinced mainly because the engine in my truck has very low mileage. less than 25k. it runs pretty dang good.. I know the pros and cons, I am worried about the hidden costs.. its not just 800 bucks to swap it.. its more like 1500 if I account for the little stuff.. has anyone got insight into the swap? going from a good sbc to a used possibly higher mileage ls?

I'd bet you'll spend way more than $1500.

When i priced out all the components i needed to put in a BD Turnkey 6.0L, i was in the range of $5k for the swap. Granted, that's on the high end, but i bet most have spent over $3k.


Keep your motor, and start stashing money away if you really want to do it in the future.

 

[sreidmx]

Thanks, It always sounds great on the other side but this really doesn't make sense now, I put a new intake on my 350 (rpm air gap) and It runs awesome now, completely different truck. All that smog stuff and carb jetting must have been causing issues. It's making 15hg at idle, and I'm pretty close on my carb tune now and it's a whole lot more responsive and torquey.

 

[Felton13]

I LS swapped my K5 a few months ago. Best choice i ever made yes it will cost much more than 1500. mine was about $5200 but i did go all out. brand new built 700r, all new gauges, new stand alone harness, radiator, tuned ecu, full bolt ons ec. ec. If you wanted to pinch pennies you could get it done for 2500-3000. but the performance you will start with is well worth it in my eyes. Putting money into an old 350 just to get it close to the HP a stock ls can do doesn't seem worth it. plus you will never achieve the MPG an ls will give you. with an LS1 you start with 350hp and can make power EASY. tune & bolt ons will give you another 65+ HP. To get over 400 hp with an old 350 would take FAR more and sill get 5mpg worse than an LS. I say sell your fresh 350, LS swap and never look back

 

[sreidmx]

Well my 350 is close to 300hp and its fresh.. I could drop 1400 and have a 420hp with heads cam alone maybee more if I didn't get a package.. I get the benefits of fuel injection but I don't see how it's worth it on a used engine that has many pitfalls.. That's all.

 

[Doppler]

It's worth it just for the better drivability alone. Start up and go, and it'll feel good unlike the older 350s that take a while to warm up in order to feel good. Easier and more fun to drive.
I have a 79 K5 with a 350 and a 74 k20 with a 5.3L
K20 is more fun to drive despite my blazer being the much better handling truck and having many more mods other than the engine of course.
Can't wait to put my 5.3/ 4L60E/ np241 setup I have into my k5 blazer!!

 

[boostdtalon]

That's the same dilemma I'm at. I was looking at going with the MSD atomic efi or 5.3 swap. I figure I would end up spending about the same either way. Still undecided but after seeing the many LS swaps on here. I'm slowly leaning more towards that.

 

[Upstate]

The 23 degree fast burn GM heads basically put the old sbc on par with the 5.3 other than roller cam. Thing is the truck 5.3 are bulletproof on the bottom end and can handle tons of hp. The gen I sbc would need some serious upgrades to be on par there.

 

[skunked]

I would focus on your suspension and getting the rig back on the trail. Once you have the kinks worked out with that you'll be looking for more power, look at the engine/trans options then. My .02

 

[boostdtalon]

My suspension is a must before the engine work. All the bushings are shot in the leaf springs and the way the truck is lifted. I want to undo all of that and do a proper suspension lift.

 

[MAX89K5]

I have $3500 in a 85k mile 5.3/4l60e (now nv3500) in my Blazer. Sanden A/C, Electric fans, everything. If I baby it, I get 14mpg on the highway. Performance is leaps and bounds over any semi stock 350 i've ever driven. Its not all about numbers to me, its the smooth and responsive throttle that comes with modern fuel injection.

Whenever you finally pull the trigger, you'll be kicking yourself in the ass because you didn't do it sooner.