Hi,

I currently have a 350tpi in my 88IROCZ. I plan to either buy a 383 and build it how i want or have my 350 bored to a 383 and build it. I do plan on keeping the TPI, i plan on an LT4 hotcam but im currently undecided on heads. I will slightly up compression but im not sure to what yet (havent gotten that into the build plan yet).

I know 383s are not cheap to buy or have built. The cheapest ive found to buy is roughly $2k. I figure itll be at least 3k in the motor when its all done. Im hoping for 350hp crank and 450LBS torque (if thats to the wheels even better lol) I know the tpi isnt a high revving intake setup so i planned to be completely done by 6k,which i believe is more than enough for a streetcar.

Ive been pondering an LS swap lately though...... I can go to my local Pull-A-Part and pull an LS for $150! I could drop it right in and just do bolt ons and ill probably be happy, itll be at least 350hp and probably around the same for torque im guessing?

To be honest I dont know much about the LS engines. So any info is good info and its appreciated. But im really seeking advice/input from people who have done the swaps; What is involved? I understand i'll need to get the computer and wiring harness and transmission too. But how hard is it to do? Is it an intense and very difficult swap or is it an easy/moderate difficulty swap? It seems like I could spend a fraction of the money to get the same power out of the LS, but the LS will also get much better MPGs than my built 383 would.

Which LS would be the best to get? What car(s) are they in?

I think ive heard of people swapping LS3 intakes onto LS1s? Why? Worth the effort?

Again, any info is helpful! And the more detailed the better! Thanks, Adam

 

Thats pretty cheap for a ls motor. Does it come fully dressed if you know? Your gonna want to get a fbody pullout if possible as they already have the correct oil pan and pulley setup you will need. And with full bolt ons plenty of people have seen around 350whp. Torque seems to be the same or a tad higher. Mpgs will be much better then with the 383. You really gotta decide what you want on this because your talking about two opposites. A 383 tpi will be a absolute torque monster down low then die real quick uptop without supporting mods. i.e. intake and maybe a little head work. Will make a very fun stoplight to stoplight car. A ls will not make as much torque down low but it will scream up top with full bolt ons. I always get a smile on my face dropping it from 6th to 3rd and punching it

If you decide to go ls, your best bet is to do what i did and get a donor car. We reused the engine, trans, rear end, dash, counsel and wiring. With the write up in the sticky, its really not that difficult or rare of a swap anymore. The worse part i think is normally the wiring. But you can do what i did and swap it over or buy a wiring harness. I know hawks sells them.
Like a said, theres tons of info on here about each setup, so read a bit more n' pick your poison!

Edit: Most people swap on a ls6 intake since they flow better and for sure worth it as your going to want the engine to be able to breath better. An ls3 intake wont fit the ls1 head style.
The most common cars ls1s are dug from are 98-02 fbodies.
Anyways do some reading in the stickies and it will answer alot of your questions!

 

If you aren't ready for alloy of wiring, stick with the tpi. That is the main factor. The wiring is no joke. If you aren't scared of that, then the LS is great. If you are happy with tons of torque, the 383 would be easily don't for fairly cheap, be ready to eat the Trans.

 

There are plenty of options for wiring for those who cant or dont want to.

 

Yep and $$$ is the answer.

 

You might be able to get an LS motor for $150 which is incredibly cheap, You will have to get a new K-Frame, Computer, Wiring Harness plus all the other stuff to make it work. IMO you would be better off building a 383.
But you stated for around $3000 you could have an 383 all done, You still have to have a chip created for your engine after completed..

 

A K member isnt required at all.

Computer is $100, if that.

Harness can vary a lot, $100 to $1000, depending on how awesome you want, how resourceful you are and how good you are.

In the end with all said and done you find plenty of people unhappy with their extremely extensive TPI builds, well those honest enough to admit their mistakes anyway, you dont hear "man i wish I hadnt gone LSx"

Youre also considering the added cost of items towards the LSx swap, but failing to recognize the parts that can be sold off that wont be needed from the existing drivetrain.

 

Thanks for all the responses guys, very informative!

The junkyard i go to is great, the prices are dirt cheap!! They do theyre pricing the same for the part no matter what car, so it could be a 1990s geo prism or a 56 Bel-air, the price for each engine is the same. So i can get the engine for slightly less than $150, and i know
I'll need the computer as well. Ill probably take the trans too, and building a trans isnt an issue-my dad owns a transmission shop

The engine comes with all accesories and as-is. So as long as I find a good one it will be ready to run as soon as i get it.

Now for the wiring- I hope i dont seem like a complete idiot for saying this, but the wiring doesnt seem like it would be that hard. Why is it? I would either put the comp where the existing comp goes and just run the wires thru the firewall to where they need to go; if i pull the wire harness from the parts car and use it on mine, as long as i label everything well, it seems like it would be very straightforward. Maybe i would need to lengthen/shorten some wires but thats not hard at all. Or i could put the comp in the engine bay and run the wires from there, lots of new cars are like that. Again, i dont want to seem ignorant or anything but i guess i must be missing something lol

So the K member is or is not needed? I would be able to just drop it right in?

Heres a list of the parts id need at the junkyard:
TRANSMISSION 5 SPEED MANUAL$57.36 (car is currently auto, IDK if i want to cut it up to swap in manual)
TRANSMISSION AUTO W/CONVERTER$57.36
8 CYL ENGINE$143.39
WIRE HARNESS LARGE$13.80
COMPUTER BRAIN BOX$25.04 >Which one? Both?
COMPUTER ELECTRONIC MODULE$14.86
INTAKE MANIFOLD V6 OR V8$27.60 (to upgrade so it breaths better)
KICK - DOWN LINKAGE$7.26
SPEED CONTROL SENSOR /GEAR$8.63
SPEEDOMETER CABLE W/HOUSING$8.21 >(not sure if these are included with price of trans)
(didnt see price for K member, if needed)

Those are the first things I could think of ill need, please tell me some more so i can get those prices too. As of now we're at $306.15, hardly $300 for an ls engine and alot of other things ill need with it lol and some of those may be included with the other parts


Now, i should say this. I want the car to be a very fun streetcar, and with that said i do think the TPI would be better in certain aspects than the ls. Im looking at 450Lbs of torque vs about 350, 100 less with the ls. My car already launches me (and anyone else in the car) back in the seat and if i have it floored i stay that way until i let off lol i was going 80 and still pushed into my seat, and its STOCK. I love torque, and to me I think the torque is the most fun aspect of the car. As I said, it would probably redline at 6k, but i will be building it up of course, and itll be a 383, so it wont run out of breath nearly as fast as the stock 350tpis. Im thinking with what i have in mind itll start running out of breath at about 5500rpms.There will be lots of porting done lol.

But the car is my DD, so it also needs to get decent mpgs (cant get 10mpgs lol needs to be more than that!) I know ls's get very good mpgs and also still deliver great v8 power. So if the LS swap costs me around 1k and the 383 is going to cost me 3+k AND cost me more in the long run, i think i will save my 2+k and drop in an ls! lol

I really apreciate you guys helping me out with this, youve got great advice and its always good to be able to talk to people who have been-there-done-that.

 

Yepper.The single regret I have is having built a 383 and not a LS. Well maybe the next one.LOL!!!.

 

You wont find any LSx engines at pull-a-part for several more years, but you can find a ton of small parts to help your build, namely wiring pieces

LS3 rectangular port intake wont fit 5.3/LS1 cathedral port heads

You'll have better luck shopping craigslist. LKQ in statesville is the only local JY that will sell LSx engines and not want your first born

 

4.8's and 5.3's are here, up where he's at I wouldnt be surprised to find an fbody...

Edit: just saw your in the same area, i'm gonna go with he's probably looking at a 5.3.

 

Fbody's pop up pretty frequently, but he wont find any LSx, because I scavenge both PAP's in NC frequently and never once has a LSx vehicle even touched the yard in the 4 years Ive gone

 

Strictly aluminum "LS" or no gen 3 stuff at all ?

 

LSx covers GEN III and GEN IV car and truck style engines. 4.8, 5.3, 5.7, 6.0, 6.2

Like I said above, if he wants one from a JY, go to LKQ, but craigslist is his best bet for a LSx engine. He will NOT find one in PAP

 

Who cares what rpm the motor turns if its fun its fun.

If you love torque and only got 3k to blow do the 383

 

If you have a decent 350 now then budget wise..build it to a 383 with good heads.Since you namely want more torque than hp and daily drive fun street car. The tried and true 383 with afr195 or equivalent heads with the 280xfi cam,longtube headers with tip..hsr would be best.You will have a 360ish whp and 400wtq combo easy.Gas mileage will really be in how well its tuned but my old setup wasnt bad for gas..roasts tires breathing on the pedal.Wasnt a great car from a high speed roll on the highway..but eats cars from light to light!

Just understand that it will be easier to build a 383 and bolt it in..but with lots of tq vs hp..you willll break parts behind the motor.Budget your self for upgrades to the trans..subframe,rearend,brakes aswell.

Swapping to an lsx really wasnt hard if you gather all the parts you need first..wiring was easy if it came off the same motor...most of the time spent wiring was inside the car to make gauges work...their fairly stand alone once you look at the pinout and delete vats.Biggest thing you need to have when doing an ls swap is patience imo.But its well worth spending the extra time to make it nice.

 

Personally after thinking about it, a vortec tpi 383 with good runners would probably be perfect for what the OP is after.