Some background info: I am 20 years old and go to college here in Macon, Ga. I am a Chemistry major and own a 1991 Pontiac Firebird. My pride and joy. Got it when i was 17 in high school. I have been working on it ever since. It started out as a 305 tbi with the NWC T5 trans. I have already swapped in a 350 SBC that blew out my weak stock T5. So i swapped in a WC T5. 5th gear went out recently on T5(probably just the slip ring). I got a 1999 Ford F150 4x4 to daily drive to and from school when the engine on my firebird decided to lock up while i was at school. I was driving down the street normal and not even gunning it when the engine just locked up. So i have now decided that since i have a reliable daily driver i am gonna make the bird my project car to work on when im not at school(so i only work on the bird over breaks since i dorm at school). I have decided to swap in a LT1/LS1 motor, T56 transmission, and 4th gen rear end. Im not sure on whether to pay to have the trans and engine rebuilt yet or to rebuild them myself, or to rebuild them at all. I am a broke college student that can only work over the summer so this swap may take a long time. lol.

Now for my questions and things: How hard is it to rebuild the engine and trans(LT1/LS1 and T56)? Would it be doable with a how to book is pretty much what im asking? I wanna get about 300 RWHP/300RWTQ, so what would be recommended for that?

Im sure i will have more questions and concerns so if you have done this swap then please subscribe. Any help is appreciated. I do all my work to my car myself and i am some what capable of most tasks. I have not yet ever gone inside of an engine though. I am going to start saving up for the engine/trans/rear end this summer and will hopefully begin buying parts for the swap. I havent decided on what engine i want yet and i have a while to since im gonna put the T56 in first, so opinions welcome. Again any pointers and help is appreciated.

 

First thing is(don't take this the wrong way), just slow down and figured out what your real plan of action is. I of all people understand what budget means, so if your on a really tight budget you need to figure out what your real goal is with your motor.

That being said, if you plan on doing boost I would suggest rethinking your powerplant to LS series, simply because if your going to spend all that cash on boost, you should have the powerplant you want, and trust me boost is where it gets expensive and confusing.

Contrary to popular belief, and LS swap is very doable on a tight budget. You find a 5.3 out of a silverado, and with the harness, PCM, and complete intake to oil pan and you could even find it for cheaper than an LT1. Some people on here have peiced a motor together for under 2k.

Don't get me wrong, I love my LT1, but I didn't know anything about the 5.3s, and how cheap and efficent they are. You can slap a ZO6 cam in it with beehive springs and have a very respectful powerplant.

Parts get expensive when you go after market, like tubular k members, Hawks LTs, 102 intake manifolds, etc etc

Don't think I'm trying to stir you away from your path, but you seem undecided so I thought I'd throw in my two cents. Good luck my friend, keep us posted!

 

Thanks. I am definitely open to opinions. Boost is just an idea. I most likely will not have boost, i was just wondering about it. And the LSX motors might be able to be pieced together but its the swap parts that get expensive. Headers cost way more...etc. Thanks though man.

 

Yes but theirs also short cuts. The LT1 swap is cheap amd strait forward but when its all said and done I bet you money you'll spend more freshening up your LTx than peicing together a 5.3, my gaskets, head work, paint, new front acc. Trust me it all adds up.

A lot of people us stock manifolds until they can afford headers, and you can score an intake for dirt cheap on 'tech. I'm just saying either way your going to be flat broke during the swap regardless, so just make sure its what you want.

Wouldn't mind another good LTx swap thread on here!

 

I hear ya. I mean i originally wanted to go LS1 but i thought it would be much more expensive. I guess the direction i go will depend on the sale i find when i actually get the money up. The first thing i will buy will be the T56 anyways, so i guess i will get that swapped in and maybe by then i will have decided which way i wanna go. Does it matter if i get a T56 from a LTX or LSX? To clarify, do i have to have a LSX T56 if i go LS1 or vice versa? Any differences in the 2?

And youre right, i definitely dont wanna spend money on something that after i swap it in i wish i wouldve gone the other direction. And i have a feeling if i go LTX that i wont be as happy as i would be with a LSX.

 

I keep editing too, because you bring up good points. Thanks.

 

Yes they are diffrent, they have a diffrent spline pattern on the imput shaft. They can be swapped out to work with one another, and its been done but I'd recommend just get the right one for the powerplant you choose.

I agree 100% though. One thing regret is not getting my trans first, its the ONLY thing keeping me from driving her after a year.

 

Anymore people wanna chime in. I have a long time to save and work on this project. I dont graduate for another 2 years so.....right now im kinda leaning towards the LS1 swap.......

 

Ls swap all the way (im a little biased). Your 91 is super ez to swap. Pocket can put you a harness together to run all your gauges and it will be plug and play. Fuel wise all you need is a pump and a reg. Its really not hard at all its just all the little things add up.

 

If you're engine is siezed up then there's no point of putting a trans in now. IMO go LS/6 speed. As it was said earlier, you can find a good 5.3 for cheap if you keep an eye out. The LT1 will cause you more issues down the line anyway. Just do it right the first time. You can do the swap on a budget, it's not that hard at all actually.

Matt

 

I was in this same dilemma for the past few years, and just decided to go LS1/T56. I had done lots of researching on which way to go and ultimately decided this would be the best option. It might be a little more expensive due to the swap parts needed, but in the end I think you will be happier. It also depends on if you want a new motor or a used. LS1's have proven themselves to be good motors well over 100k miles. I would definitely hold off on buying a T56 until you absolutely decide which way you are going. It would be costly to make a lt1 t56 fit an LS1, an expense you might be able to avoid. If you have time and patience, in my opinion it would be best to try and find an entire 4th gen car, take what you need, and part the rest. Doing it this way you could make up a lot of your money back. Depending on where you live, you could find one locally that way shipping wouldn't kill you. Just do your research, and be careful on who you buy from. There are some shady sellers of LS1 stuff with ridiculous prices. Take your time and good luck. If you get serious about going LS!, let me know, I can get you the name of the guy I bought mine from. A+ guy!

~Steve

 

Gauges are not plug and play, speedo needs wires jumped on buffer box, fuel gauage needs new resistors or the sender replaced. Just want OP to know that not everything is plug and play.

 

why does the sender need messed with? I dont see a need for it unless you are swaping in a 4th gen tank. You are right about it not being plug and play but you arnt going to be out a lot of money like us folks with the cable driven speedo's.

 

True about the fuel, i overlooked that, but seeing how the LS motors need more PSI, cheap route is a 4th gen tank with lines, cut at the center of the car and runa single line from there to rail (VS buying an expensive external pump). The speedo is different, this thread pertains to the OP's car which is a 91, it should have a buffer box behind the pass side panel/dash. i believe 88 or 89+ firebirds had the electronic speedo's. I wouldnt know what year car you have since your avatar doesnt tell me much.

 

Change the input shaft, bell and midplate to LS1 variants.

Average price of LT1 Bell $125

Average midplate price (LT1) $50

Average price of Lt1 input shaft $125

Kickback = $300

Average out of pocket cost of LT1 to LS1 T56 conversion $150


Sell off the Lt1 **** on ebay.

$150 more to convert a T56 from an LTX car isnt alot of money when you cant find any other T56's around.

 

i just did my LT1 swap last year. i got a 96 OBDII stock 72k mile engine from pan to wirining harness and ECM for $600.. it had a blown head gasket.

i tore it down to the short block, had the heads tanked, new gaskets all around, tuned, wiring harness done.. i think i spent an additional $1800 to $2000 on it, since i did a cam swap and exhaust too.

there are deals out there, but you need to make sure you get a COMPLETE engine, or all the stuff is going to nickle and dime you to death..

IF.. i wasnt so impatient i could have gone the LSx route, but the LT1 engine has a lot of potential. if you're not after 450rwhp..

quite frankly.. alot of these guys trying to build these 450+hp cars rarely ever use it, unless its a track only car.. and then i see them have nothing but trouble with their builds.. and they spend close to $10k on the engine alone.

if you keep the engine close to stock as possible and try not to run too many aftermarket parts, the engine will be very reliable, either LSx or LT1...

 

Im kinda biased
So i think a ls based swap is your best option. A t56 behind a stock 5.3 will be very reliable,drivable and fun to drive. and will run on 87 octane all day long.
The cam in a 5.3 was designed for a heavy vehicle thats was also meant to tow. So it will be very pleasureable to drive in a lighter 3rd gen.
I speak from experience. When i was putting together my 6.0. I sold my ls1. I dropped in a stock 5.3 just to drive around. It was fun, i beat on it. Ran it on 87 octane. Never complained. This was in my full bolt ons, ls6 intake TA.with a tune.
I will take a stock 4.8 over a Lt1 anyday. But thats just me

 

Rear engine 3rd gen?

 

It was the stock 3.42(at the time) rear end. This was in a 99 ta. But i believe the 3rd gens are significantly lighter than the 4th gens. Mine was full weight and then some.
The stock 5.3 ran very well imo. 100% stock longblock.
I used the stock ls6 intake, existing lt headers,exhaust.
I think the 5.3 would work very well with a t56 in a 3rd gen.
With bolt ons and such.
If the op cant source a 6.0,ls1 or higher end ls motors

 

i think he meant you said put the engine behind the trans lol

 

 

ls