Aurora/other V8 engine swap?

turtleman wrote:

I'm trying to encourage this swap, Derek

Me too, but to take the transmission as well.

hey i was just wondering how hard it would be to put a LS4 into a 96' riviera? my engine is starting to get into pretty high miles, and instead of building the series 2 i would like to save up and put in a LS4. Would it be a difficult swap? Has anybody done it? I think it would be badass to have a newer rivi with a v8. Let me know. thanks

Regarding the northstars - I bought a complete set of GM shop manuals for my 98 Riv, and the manuals also cover the Aurora as well (and includes data on the 4.6 Northstar engine servicing, so part of the manual may be crossed with the Eldo). If I understand correctly, a Northstar swap would be pretty simple. You start with an Aurora engine cradle, use the Caddy engine and tranny (bolts right onto that cradle), use the Caddy computer, and it's possible to literally unplug the 3.8 computer and plug the 4.6 in.

At least, after several readings of multiple sections of the manual, that's what it says to me. No, I haven't done it, and I'm trying to decide if I want to.

The GM LS engine in the Impala has MUCH more complicated electronics - besides lots of fabbing, there's lots of electronic and computer work to be done.

BigTexKahuna wrote:

I'm 54 years old, and I've had more cars over the years than I think I can count. My very first car was a hand-me-down 1969 Datsun 510 wagon... I bought it from my older brother when I was 16. During my college years in the early to mid-70's, I had a Datsun 1600 sports-car, and for awhile in the mid-80's, I owned one of the first 'hard-body' Nissan 4-wheel drive trucks... a 1986. While the first two Datsuns were 4-cylinder motors, the truck was a V-6, and that was the first and only 6-cylinder vehicle I'd ever owned... until now. All the other cars/trucks in my life have been USA-made V-8's, and most have been GM products. As a matter of fact, I've manged to own one or more of each of GM's brands... except I've never owned a GMC truck or van... well, my company's delivery truck is a GMC, but it's actually an Isuzu with GMC's badging on it, so I don't suppose that counts, does it?

My '95 SC Riv is my second Buick. Back in '88 - '90 I owned a '72 Centurion Coupe... that monster had the awesome 455 under the hood, and I did a few modifications to the car to bump-up the horsepower... a truly awesome machine that Buick! I changed out the exhaust... turned it into duals with Flowmasters... really made that big-block sing in 4-part harmony.

Like someone's earlier post in this thread... I, too, prefer the sound (and power) of V-8's, but I have to admit, I'm impressed with the power of this 3.8L V-6, and the supercharger makes a rather significant difference. Also, the older I get, the more the need for speed seems to diminish. What I like most with these 9th Edition Rivieras is the look... I truly appreciate the over all design of this car, and I love the simple analog layout of the instrument panel. This is one of those 'love 'em, or hate 'em' kind of cars, and I think mine is just simply a sexy looking automobile! I've had people ask me if this car wasn't a Jaguar on several occasions...

So, as far as a 'concept'... GM should have offered a V-8 option with these Rivieras. They should have provided Cadillac's Northstar V-8 at 300+ horsepower with a heavier-duty, more reliable transmission, beefed up the suspension, slapped on some 18" wheels and tires (I did do this for my Riv), and zoom-zoom-zoom, the Riviera would probably still be on the market today. That's my idea of the 'Dream Riviera' for this generation... but I'll take a 1971 Boat Tail in mint condition ANY DAY! A white one with red interior...

I agree. They should have given the option to have the Northstar V8 as well as the SC and NA 3800's. They couldve gone with a complete woodgrain interior, 17 or 18'' wheels, some chrome exhaust, and they wouldve had a winner.

On the CON side of having a Northstar.....not only is it expensive to fix, the repairs are labor intensive. Not to mention they leak from EVERYWHERE too....

Both of my brothers had to have alternators replaced in their Aurora's and one of them paid $90 to have his friend install it and it took 3 hours. He ended up having to remove the radiator to reach it because its such a tight fit in the engine compartment. My other brother is having his done right now and the guy said it would only take about an hour or two because he didnt remove the radiator to access the alternator. Thats the biggest negative I have about those cars/motors-that the entire engine bay is taken up by them and leaves you no wiggle room.

Off topic, but another thing I find odd is that sometimes a girl will say, ''Oh what kind of car do you have?'' and when I say Riviera, they are confused and say theyve never seen one, and I have to tell them its the two-door Aurora, and they instantly know what it is!

tell em its a "one off" Bentley.

i wanna swap out my engine for sum more power wut all wud i need to change 2 drop it in i know itll fit it s jus gone b a tight fit but wut all do i gotta do plz try 2 stay on topic im tryna get it done this summer and i need info asap........97riv sc

Easiest thing that comes to mind would be the Northstar 4.6L, or even the 4.0L Aurora V8. Although I'm not sure on the available mods for those engines.

Personally, I would think the Series II SC is waay more mod friendly and can see as high if not higher output numbers than the Northstar. Typically anything that says Cadillac on it tends to be a little scarce 4 mods and if it even can be modded, it would be stupid expensive.

with Klix on the mod friendly part. Your going to spend wayyyy too much money trying to get a V8 in that car, let alone get it wired and running correctly. I would take the money you are planning on spending on that V8 and just build a mad boost friendly 3.8L

Aside from getting a CAI, exhaust, and maybe a PCM tune on a Northstar, there are no mods. Please disregard this post if you are planning on making a drag car, gutting the entire thing, and running a carbureted engine, as that would be the only "easy" way to do it. Oh, wait, I forgot about trying to mate a trans to that......AND make it rear wheel drive.....

You can mod your 3800 to go as fast as you want on the street. No one on this board has done a V8 swap in a 95-99 Riv.

However, there IS a V8 Riviera (98?) that GM made for prototype purposes, that was available for sale very recently. Don't recall the price (not cheap) but it would have been the way to go if you really want a V8 Riv.

Abaddon wrote:

with Klix on the mod friendly part. Your going to spend wayyyy too much money trying to get a V8 in that car, let alone get it wired and running correctly. I would take the money you are planning on spending on that V8 and just build a mad boost friendly 3.8L .

agreed. Ive done engine swaps and they can be a nightmare. Just get a car with a v8 already in it....

i love the body shape of the 95-98 riv i want a v8 sound pouring out wit v8 power behind it das y i wanna do a swap but i dont think ima have the tym 2 do all that any more.......can some one give me a list of mods i c do 2 get it sounding and performing close 2 that of a v8.......oh and i wud like 2 stay supercharged love the feeling of pullin away from ppl off the line.............p.s cost isnt really all that important 2 me i want the best 4 my riv....

Just browse the forum man. https://rivperformance.editboard.com/series-ii-engine-transmission-f4/. Here's a start. Any questions and most of us can (and are willing) help you.

The only LS series engine that would work would be the LS4, as all the other LS engines have too long of a crank snout, though I suppose it is possible to swap a LS4 crank into a LS2 and just use the LS4 accessories.

Abaddon wrote:

Just browse the forum man. https://rivperformance.editboard.com/series-ii-engine-transmission-f4/. Here's a start. Any questions and most of us can (and are willing) help you.

best advice ^^^


My riv definitely has "V8" power if you want to think of it that way. But you'll never ever get a "V8" sound from the 3800. You can make it loud if you want, but you'll never make it rumble...

any exhaust on the Riv is going to be custom, so if you are going to do a serious performance buildup, you'll probably end up with headers and a custom exhaust system anyway. There is an exhaust thread with a lot of different video clips. Listen to them and ask around, then have a local custom shop do your cat-back as you desire.

Headers and exhaust will give your Riv a nice deep sound.

I'm tempted to do this I figure most parts could be taken from a 92 Caddie STS and possible a newer 4.9. Anyone done this swap? It seems like a very easy swap to do and the option of dropping a carb would make it even easier.

I know how to do that- FWD, RWD, 3.8, 425, supercharged, AFB all in two.

I don't know much about engines but I apprenticed for a summer or two(didn't learn anything)with a master mechanic,and he informed me that the Northstar engine is the biggest piece of crap that he ever had the misfortune of laying his hands on. And that Northstar engines are like a fine wine,they run great when running right,but need constant fiddling with,periodically turned over,and should never be set in direct sunlight,in other words,park em and forget em.

^^^ The Northstar was GM's response to the OHC V-8's from the European competition. The target market for Cadillac was moving over to these other big cars, and Cadillac needed an engine that offered the same "smooth, refined" performance (a smallish, high-revving V-8). And they did it well - it was masterfully engineered. Ward ranked it on their ten best engines list 3 years in a row.

Two problems with the Northstar V-8:

1) Domestic car makers, especially GM, can't seem to get away with making high-maintenance products like the so-called "finer quality" Euro cars can. If a Volkswagen needs a strict dealer-scheduled maintenance regimen, including mandatory timing belt change at 60k miles, the perception is that the VW needs that extra fine tuned maintenance because it's a higher quality, performance machine. But try that with a Chevy Cobalt (a car that competes against the Golf) and people will say it's junk because it requires the extra attention. When the front suspension system in an Audi S4 needs work, the high expense is due to the steering design being a performance oriented, innovative design. Cadillac's expensive air suspension used on the late '90s STS is considered by many to be too expensive to be worth repairing.

The market perception is, if domestics don't last forever with anything more than basic oil changes, then they're crap. But the Euro brands (and to a much less extent the Japanese), often having serious reliability issues of their own, are often passed off as "high-precision" machines that need special care and attention, and of course special owners who can afford the added expense. Consider a $200k Ferrari, which typically needs an entire engine rebuild by 50k miles.

2) Domestic loyalty can be a real pain in the ass. When Cadillac went after the big car luxury market, being dominated by the European and Asian brands, they forgot about who also wanted a Cadillac: die-hard Americans from the hot-rodding era. Maybe it didn't make sense from GM's perspective at the time, but changing over to aluminum DOHC design and abandoning the old iron push rod V-8 turned off a lot of folks, imo. Corvette survived, and Buick did well enough using the 3800 V-6. Those engines are what we used to do well, and once perfected, we dropped them.

No wonder lots of mechanics and other domestic enthusiasts want to think the Northstar is crap. They never even gave it a chance. It was hated from the day it was introduced. Someone's probably still saying, "Yeah, GM sure messed that one up - they should have stayed with what worked." I think all of us can agree with that a little bit. But I think everyone also knows that car makers need to sell cars to stay in business. I think GM made the right call with the Northstar, and I don't think it was fairly received by the public.

robotennis61 wrote:

I don't know much about engines but I apprenticed for a summer or two(didn't learn anything)with a master mechanic,and he informed me that the Northstar engine is the biggest piece of crap that he ever had the misfortune of laying his hands on. And that Northstar engines are like a fine wine,they run great when running right,but need constant fiddling with,periodically turned over,and should never be set in direct sunlight,in other words,park em and forget em.

@ AA: I don't know about all that.Many of our customers had Northstar equipped cars in various stages of age,meticulously maintained,yet still had problems.Many of them could not wait to trade them up.The Northstar engine was a common topic in our neighborhood,Long Islands main cadillac dealership was right up the street.The Cadillac dealership would Actually send my boss the cars they could not fix,Most of these cars with problems particular to the Northstar engine.
Not to mention Cadillacs terrible electronics.