zak91rs

Hi guys, I'm about to procure a 1991 RS with the LO3 V8, auto trans from a dude that lives nearby me and intend on making it a project car aside from my daily driver which is a '97 Pontiac Grand Prix GT, which is stock except for new tranny and audio system. So naturally first i went online and read everything I could about 3rd gens, and I learned a lot but I'm not exactly any sort of car whiz(yet, I'm working on it). So there's obviously a lot of options here I could do but i'm basically looking for someone to help me out by showing me a build sheet of some sort for mods i should do in order.

Obviously i'm gonna start with average tune up crap, new spark plugs+wires, flush coolant, oil, new tranny fluid etc. But after i'm ready to go on all that and begin safely modding, I'm not exactly sure which direction I should go. I'm not rich here, so I'm kinda looking for the most cost effective way to go vroom.

Now I'm not sure if it would cost me more if i were to stick with the L03 and beef it up or go for the LS1 swap (can I even do that with an auto tranny?). But anyways if I do go LS1 I'd like to know what i should consider and buy, or more preferably, if it's realistic, how can i make the most out of the motor in there now? I'm willing to supercharge or turbo, or cams, or whatever you guys think is the best way to get this car to be bad-*** with limited expertise. So lay it on me guys, tell me what you think.

1ADan

iTrader: (4)

welcome aboard

there's a ton of info in the LTx/LSx subforum here, but an LS swap is not a beginner move by any means (or cheap). Read the stickies over there and see if you feel comfortable trying to tackle the project.

a slightly easier and cheaper route may be doing a 350 swap - overall bolts right up, more power, and a good way to get some wrenching time before doing the complete overhaul an LSx swap would require to be done right.

zak91rs

yeah, it looks like youre probably right the LS1 swap looks pretty difficult after i looked into it more haha. how much do you think a 350 swap would run me, and what do i need?

1ADan

iTrader: (4)

all depends on how far you want to go. if the car is still bone stock, start with the stuff that will get you the most out of any engine upgrades - intake and exhaust. if you want to get some more power out of the LO3, you could always add an LT1 cam, headers/catback exhaust. the exhaust will work on a 350 as well.

if you're looking to go up to a 350, the vortec engines are pretty easy to find, have a decent set of heads on em (for a factory piece), and should be relatively cheap used. if you stick with tbi, you can get an intake that will let everything swap over.

with any fuel injection swap, you won't get the most out of everything without a tune, so keep that in mind

camaronewbie

And what he means by a tune is custom chip tuning - very hard to come by for the TBI setup - there's just not alot of tuning can be done with TBI, and very few (if any) folks do TBI tuning anymore. You can get the pc gear and learn to do it yourself, but it's a lengthy process (days/weeks/months of driving around with the laptop plugged into the car changing numbers on-the-fly), and a large learning curve (if you have no programming knowledge or car knowledge).

You can drop in a 350 motor that was already TBI (like from a truck or Caprice), swap in the 350TBI chip into your ECM, and install a knock sensor for a 350TBI and 350 injectors, and have a running 350TBI with little issues.

You can also go carbed (assuming your state/county allows such) and that will allow to to swap in any Chevy hp monster of your choosing. Just need a fuel pressure regulator (if keeping in-tank fuel pump), and if auto tranny a method of locking the torque converter and correct bracket for the TV cable.

As you can see by my sig, I went carbed - I can "get away with it" in NC, and it was easier to me. $600 on a complete running 350 carb to pan (used), another $300 in misc stuff. I ended up have to do a tranny rebuild - with the 305 my tranny was fine, but once the 350 got ahold of it, it slipped badly - so always expect a tranny rebuild/replacement. Any 350 will swap in, only concern is heads and them having the mounting holes for your accessories (most heads 1973+ have them).

IMO - the 305 is just not worth any effort other than basic tune up (cap/rotor/wires/plugs/filters/oil). Although a few have gotten some decent numbers out of one, you just spend a ton of money on something that will never out perform a 350.

Really, the sky is the limit (well, your wallet, time, energy & patience are the limits). With a large enough hammer, a good enough welder, a full wallet, and alot of time, you can swap anything in there. But a 350 swap is simple process, whether carbing or keeping the TBI.

camaronewbie

You should also consider suspension and brakes before motor swaps. Assuming that the car has never had any suspension work done (which is usually the case), it needs new tie rods, ball joints, centerlink, idler arm, bushings all around, shocks, struts, springs. That's a healthy chunk of change to start with - $500 - $1500 depending on what brands you choose. You also should, BEFORE anything else, get a wonderbar either from local JY off an IROC or from TDS (a sponser here). Every 3rd gen should have had one, but they only got installed on the IROC's - it greatly reduces stress on the front where the power steering box is attached to the frame - often the frame gets cracked there from lack of it.

Brakes - new pads, fresh rotors (whether turned or new), a fluid flush are in order more than likely. And - there's nothing more amazing for brakes than replacing the rubber brake lines - makes a ton of difference (and they never get done until they bust and leak). There are 3, one each wheel on front, one driver side rear.

Good Luck! Most importantly, have patience, and have fun! And let us know what you decide.

zak91rs

Hmm seems I have lots of options. I'm probably picking the car up this week, which I am psyched about, and once I get the floor repaired (which thankfully is the ONLY thing with any rot at all) and some paint on her, I'm gonna go for the 350 swap. Should I just look for the stock Z28 350 at my local JY? or are there any other easy fitting 350s you guys recommend?

90blkrok

check your local machine shop. sometimes they have short/long blocks that customers seem to forget about. they sell'em cheap.

camaronewbie

As far as fitment, any 350 - they are all the same until you get into the LT1 or LSx motors - no special mounts or anything. Mine is a late 60's block with 70's heads. Power is made in the heads - they are the important part - heads can make a 350 200hp or 800hp. But heads are changable without yanking out the motor again - can always improve on just about any 350 block.

torque_is_good

Someone has to say it

you have said that you are on limited funds and limited knowledge yet now speak of getting an engine from a junk yard and swapping it.

If performance is what you want, and you don't own the 305 TBI vehicle, then don't buy it; seriously.

There is absolutely nothing wrong with an LO3 F body unless you want to be running 13's in the quarter. They don't perform like the new 5.0 Stangs or new SS Camaros and they don't even perform like the 4th gen LT1s and LS1's. They are from the 80's, you know, when 100HP was considered a lot.

So, if you don't own the car, have limited resources and experience, and want to go, as you said, vroom, don't buy it. I would suggest looking around for a different vehicle, perhaps a TPI version. But, then you'll hop into a 4th gen and want that kind of ride and performance. There will always be faster cars.

But, to get caught up in the debate that only a 350 is areal engine is utter nonsense. If that's the case, then bore it .030 and stroke it and make it a 383 which is more of a real engine or find a 400 which is even more of a real engine or.................

do you get the picture?