The ever popular domestic V8 swap.. A few questions

[genocide98]

I've got a 1984 BMW 318i with an automatic transmission that is currently being overhauled. I bought a parts car and I'm currently mixing and matching to get the best looking, running and driving bimmer for my $750 I have spent so far.

Now, this leaves me with a BMW carcass. I'm debating its fate... Either-

Option A: Part it out for what I can get and then use the money to send it to the scrapper...

OR

Option B: Fix er up and give this bimmer its second wind.

The selection, however depends on what kind of feedback I get from various communities and friends that I'm asking. I honestly can't decide myself and hopefully other people's opinions and experiences, when taken with a grain of salt, will help move me to choose one of the two.

The car as it stands (my non-driver, which is being worked on and assembled now) is, like I said, a parts car. Extra work (outside from the swap) is not really a big deal as it will be a project and thusly completely custom. It's in rough shape body-wise but there is MINIMAL rust and it looks to have been garaged its entire life until an unruly teenager got his hands on it and got hit in it. It doesn't have to run or drive until the project is complete.

I'll be doing 99.9% of the work myself and I should have enough money for either option (young with three passions, cars, guitars and women. I have no woman at the moment and I already have my guitars...) and aside from college and living expenses (rent and utilities) I wont have anything to free my wallet from all of that dirty stinky money.

So here comes the debate. Domestic or Foriegn?

Foreign:

My first thought was- BMW! Lets stick with it. I like BMW, I like their approach to automobiles. I think they have great products. Then I started looking at the price tag. Then I started looking at the price tag for the mods. Then my balls receded into my abdomen as I curled into a fetal position. Its EXPENSIVE.

The biggest value for swapping a BMW engine was to try the M50 or M52 of an e36. The engine is easier to find than an S, cheaper than an S and still a strong platform to work with. its also cheaper to mod than the S engines, which I also liked. Would this be a relatively accurate assessment, my fellow forumgoers? Sacrifice some performance in the sake that I wont break the bank completely seeing as how I'm not THAT well off to do.

The Domestic option to me was clear-

I'm a Chevy fan. My father, who taught me everything I know about working on cars is a Chevy fan. the only other option would be a Mopar 340. Much like the M50/S50 debate, while the Mopar would be a great choice (the formula S 340 smoked almost every big block of their day off teh line) it is simply too much money and too rare to find parts for.

Now I'm relatively farmiliar with a Chevy small block, particularly the 350, but can anyone tell me why everyone seems to be swapping the LS-1 into BMWs other than the 100lbs or so weight difference? Is it the modern aspects of the motor such as the up to date fuel injection, aluminum block and engine management systems? Or do they simply not prefer to tackle the carburated 350 of the olden days?

I know its -very- easy to build an older model performance 350. Especially in the United States. Building a domestic engine is dirt cheap in comparison to building higher end imports such as BMWs or a skyline, supra, ETC. Not only new parts, but used parts are in abundance. If you aren't worried about the extra pounds of a cast block you can pick up a 350 short block with a four bolt main starting at $150~

Is it possible to swap a classic cheverolet small block into a BMW or would it require excessive hastle (can you be descript) over the LS-1 or another modern-generation small block? Is it too big? What about big blocks such as the 427 or 454?

What work goes into the car other than just the engine swap itself? I'd imagine I'd have to strengthen the frame accordingly. What about the rest of the drivetrain, rear end, etc? Tracking this car, if it pans out, is up in the air. I'd like to do it if for nothing other than shits and giggles so I'd take into consider aspects of the suspension which need to be modified into this as well.

How about transmissions? What would you guys think of seeing a two speed powerglide trans in a bimmer?? or stay with the six speed?

Any kind of estimates as far as cost (non-engine) would be nice.

Also for the fab work- manifolds and mounts...? I might be able to get the mounts and frame work done relatively cheap but I'm not sure about the manifolds...


I appreciate the help and I'll continue to read up on the subject. Its a bit long winded but I REALLY want to make this happen. I think it would be cool... Its kind of adapting what I love (Bimmer styles) to what I know (american muscle). Looking forward to hearing your replies, criticism, etc.

-Brad

[rao]

People choose LS1s and LS2s because they are throughly modern, light, relatively inexpensive, powerful (and easy to make more powerful) and are much easier to make emissions compliant on newer cars.

There is no reason a carbed SBC (or TPI motor or a LT1 for that matter, which use essentially the same block with factory fuel injection) can't be used. But you can't beat the driveability of the more modern engine.

[JoeZ]

I would say that weight is the major factor when BMW owners look for a non-BMW powerplant.

[nbirru]

wow... I was about to post this exact same thing. I have a 318I chasis right now with no fuse box or wiring and my friend is trying me to put a 350 in it. He was trying to tell me how cheap I get this all done for since he can weld and parts are ridiculously cheap. Basically I could get the whole car up and running for under $1000. And from there the mods on the engine are pretty much endless. One of my friend dumped no more than a thousand into his 350 in a chevy and had it easily over 300 hp with a lot of torque. So I think we should continue this dicussion further.

[Dungbeetle]

wow... I was about to post this exact same thing. I have a 318I chasis right now with no fuse box or wiring and my friend is trying me to put a 350 in it. He was trying to tell me how cheap I get this all done for since he can weld and parts are ridiculously cheap. Basically I could get the whole car up and running for under $1000. And from there the mods on the engine are pretty much endless. One of my friend dumped no more than a thousand into his 350 in a chevy and had it easily over 300 hp with a lot of torque. So I think we should continue this dicussion further.

I think it's a good way to get going. I doubt there would be that much weight differential. But, if it becomes an issue, you can always switch over to an aluminum old style small block. There are plenty of them available. The newer engines are much more sophisticated in attacking problems like emissions and fuel economy, but also much more complex. I like the simplicity of the older setups. There are decent aftermarket fuel injection setups available for them that will be much simpler to wire.

Somebody must have done this already. If not, let's get a consortium going and share info.

[SPElectronics]

I too have a 1984 318i and plan to do a motor swap, and was debating between the M50 and a Small Block V8. I already have an aluminum V8 sitting here from my Range Rover, so that is probably going to be the direction I go, provided I can figure out how to make it all happen. Have to pic a trans, etc. to go with it as well.

Hopefully this thread takes off, and we can see what others are doing/have done already.

[autophile]

I'd love to put an LS1 in my E34, but even that "bargain" seems out of reach of my budget right now. So I'm considering an LT1/4 and save up for a future LS1 into something else, like an e46 M3.

Back on topic:

I think that in an E34 (vs. an E30 or E36), the extra weight of the iron block will not be as noticeable. Other things like relocating the battery to the trunk will also help keep the car BMW-balanced.

I also like the availability of cheap upgrades for these engines.

Knowing a few race car fabricators and engine builders helps, too. Volunteering to help them out between races and at the races helps more!

I'm really looking forward to the project, and more to come. I hope to start sometime this summer.

[genocide98]

I'd love to put an LS1 in my E34, but even that "bargain" seems out of reach of my budget right now. So I'm considering an LT1/4 and save up for a future LS1 into something else, like an e46 M3.

Back on topic:

I think that in an E34 (vs. an E30 or E36), the extra weight of the iron block will not be as noticeable. Other things like relocating the battery to the trunk will also help keep the car BMW-balanced.

I also like the availability of cheap upgrades for these engines.

Knowing a few race car fabricators and engine builders helps, too. Volunteering to help them out between races and at the races helps more!

I'm really looking forward to the project, and more to come. I hope to start sometime this summer.

I'm pretty much stuck with a 3-series myself, unfortunately. Although I don't really need much help for working on it ETC I can see your point being very valid: befriend those with experience and expertise and it will benefit you greatly in the long run! Knowledge is power and they can often take someone's n00b-to-car idea and break it down from the standpoint of a mechanic.

I'm fairly certain that you can directly swap the 350s, so if you were to, say, find an LT-1 (an LS-1 is only ~$2500 for the entire drivetrain.) for now, you could swap in another chevy 350 in later when you decide you want to upgrade.

Unless of course you want two chevy powered bimmers...

I think it's a good way to get going. I doubt there would be that much weight differential. But, if it becomes an issue, you can always switch over to an aluminum old style small block. There are plenty of them available. The newer engines are much more sophisticated in attacking problems like emissions and fuel economy, but also much more complex. I like the simplicity of the older setups. There are decent aftermarket fuel injection setups available for them that will be much simpler to wire.

Somebody must have done this already. If not, let's get a consortium going and share info.

Quite a few good points. I like the classic simplicity as well, mostly because its going to be easier for me to transplant, though.

wow... I was about to post this exact same thing. I have a 318I chasis right now with no fuse box or wiring and my friend is trying me to put a 350 in it. He was trying to tell me how cheap I get this all done for since he can weld and parts are ridiculously cheap. Basically I could get the whole car up and running for under $1000. And from there the mods on the engine are pretty much endless. One of my friend dumped no more than a thousand into his 350 in a chevy and had it easily over 300 hp with a lot of torque. So I think we should continue this dicussion further.

To put this simply: Most 350s make anywhere between 250-300hp stock. The LT-1 (from the early 70s corvette) made around 375 and basically its the fastest STOCK 350 of its era. They're pretty hard to find as they were produced for only a very short time.

HOWEVER, if you don't plan on keeping the motor stock (I certainly am not) then the base you use for it is relatively less important.

Like I said in my first post, parts are readily available and the 350's lifetime has spanned almost fifty years and its still going strong. There are tons of parts and you can get a 400-450hp car pretty easily without having to go into Forced Induction (Superchargers, Turbochargers) for much less than most cars.

The main debate to me seems to be a cheaper and easier setup with more mods for cheaper VS lightweight, modern and more driveable at higher HP ratings (over 400 I'd say).


Well apparently the decision (on my end) has been made: It shall be done. I'll have a 350 bimmer if my life depends on it.

Now I just have to talk my dad into kicking down one of his small blocks for me to use

Any other suggestions for mods on the car? I need to start looking ASAP. Summer time is coming and with the weather comes the work!

[Dungbeetle]

I've heard that 302s out of fox body mustangs are smaller and lighter than the classic small block chevy, and they are readily available. Has anyone looked at them?

[nbirru]

I don't have to pass emissions in my state as we never have any tests but for everyone else is there a way to pass emissions with a carburated 350 in an obd-1 car (e36) or is that pretty much impossible?

[LeMansGT]

I've heard that 302s out of fox body mustangs are smaller and lighter than the classic small block chevy, and they are readily available. Has anyone looked at them?

A Ford 5.0 is physcally smaller than a traditional GenI or GenII Chevy Small block. GenIIs were the 90s LT1s.

Gen3 (LS1/LS6) and Gen4s (LS2) are smaller than the GenI and GenII motors despite bore spacing and deck height being the same. The Gen3s and Gen4s have a shorter intake and take up less room from to rear. The motor mounts also changed with Gen3s.

[LeMansGT]

I'd love to put an LS1 in my E34, but even that "bargain" seems out of reach of my budget right now. So I'm considering an LT1/4 and save up for a future LS1 into something else, like an e46 M3.

If you are willing to give up the weight of an iron block and you are on a budget I would look into the 4.8 or 5.3 truck motors. The computers, hoses, engine mounts, etc will swap over to a LS1 and with a few mods a LS2. The Lt1/Lt4 swap would require everything to be changed and most likely make less power in stock form.

[rao]

If you are willing to give up the weight of an iron block and you are on a budget I would looking into the 4.8 or 5.3 truck motors. The computers, hoses, engine mounts, etc will swap over to a LS1 and with a few mods a LS2. The Lt1/Lt4 swap would require everything to be changed.

That's a good idea - the iron blocks weigh around 80 lbs more and they are a l ot less expensive.

[nbirru]

My chevy monster truck friends are starting to slowly convince me to put in a carburated 350 in my empty 318i car. I went over to their house (where I also keep my 318i at) and looked at their various setups and it seems like it wouldn't be a whole lot of work. Wiring is etremely simple, they already have a solution for the throttle cable... they all use aftermarket gauges in their truck already. The hardest part would be fabricating engine and tranny mounts they said although that would be a small struggle for them. The tranny would have to be an auto if I wanted to save on complexity and cash. Then i would also have to get a custom drive shaft. But they would be able to fit in the radiator and attatch everything else. To get around the steering column with the headers/exhaust they said they could swap headers from right to left running the exhaust forward then looping under. For around $600 I could get a 350 engine and auto tranny with 250+ hp. They said for under $1000 I could have all this running and working right. Also with a 350 engine the cost to get 400 hp out of it is extremely low... but I would have to work on the rear of my car first to make sure it could handle that.

[autophile]

If you are willing to give up the weight of an iron block and you are on a budget I would look into the 4.8 or 5.3 truck motors. The computers, hoses, engine mounts, etc will swap over to a LS1 and with a few mods a LS2. The Lt1/Lt4 swap would require everything to be changed and most likely make less power in stock form.

Good point. I'll look into that.

[moorepwr]

There is also a carb intake and new front cover for GenIII/GenIV small blocks that uses a small block ford distributor of you want to go low tech.

Car craft has a great article from April 2007 where they used the carb intake on a LQ4 to make 480 hp.

The Gen III engines make great power without using a hairy cam.

A GenI/GenII small block can make the same numbers but without the driveability.

[e31bubba]

I don't know what state you live in but I do know in Ca if you do an engine swap you have to have a referee smog you car and it's is ALOT easier to pass the ref inspection with and older chassis and new engine then a older engine and a newere chassis because you have to pass the smog regs of the body of the car for instance a 96 car only needs to be up to 1996 standars so if you bring a 96 car with a 2001 engine you have alot easier time then brining a 2001 car with an older engine

[MWrench]

In California, you can not put an older year engine then the car year. This is after 1975. All smog equipment that was with a particular model year engine MUST be included and operable in the conversion. In the case of the LS1/LS2/LS6, even the fuel tank vent/valve system is controlled by the ECU and must be included in the conversion and will be tested by the referee. Headers can not be used unless they have an E.O. number or C.A.R.B. approval and number.

SMOG standards are to the engine year not the car year! So if you put a 2001 engine in a 1976 car, it must meet the standards for 2001. We do not have a rolling exemption for model years any longer either, 1976 and newer cars will be subject to SMOG testing and certification and the year 1976 is a fixed starting point. Even in 2026, a car being 50 years old will have to meet and pass a SMOG test! 1975 and older cars are SMOG exempt.

If you follow the rules, I guess it could be call easy, but there are MANY rules to know and follow!

HTH

[AutoRotate]

[QUOTE=nbirru;9019204] They said for under $1000 I could have all this running and working right. QUOTE]

Having done a lot of research into engine swaps of all kinds, I'd say these guys don't know what they're getting into. No offense to them, but you should get these guys to put this into writing for you, drop off the car and say "good luck." I am 99% certain that they will not be able to have your car "running and working right" for under a grand.

[nbirru]

[QUOTE=AutoRotate;9096397]

They said for under $1000 I could have all this running and working right. QUOTE]

Having done a lot of research into engine swaps of all kinds, I'd say these guys don't know what they're getting into. No offense to them, but you should get these guys to put this into writing for you, drop off the car and say "good luck." I am 99% certain that they will not be able to have your car "running and working right" for under a grand.

This isn't for them to be doing all the work. And they wanted to just put in an old carburated 350 engine and tranny that would only have a little more than 200 hp probably around 600 for full running setup (out of an old chevy) and the rest would be custom work I would pay for parts and beer. But they would do most the work free or extremely cheap just because they are friends. I've already seen some of their work when they dropped an ls1 into an old antique car and did all the welding and everything. The setup looked pretty nice and this is basically the same idea. The only part I really have to pay for is getting customizing the driveshaft.

I don't know what state you live in but I do know in Ca if you do an engine swap you have to have a referee smog you car and it's is ALOT easier to pass the ref inspection with and older chassis and new engine then a older engine and a newere chassis because you have to pass the smog regs of the body of the car for instance a 96 car only needs to be up to 1996 standars so if you bring a 96 car with a 2001 engine you have alot easier time then brining a 2001 car with an older engine

I think a lot of people on here don't have any smog in their state. I've never had to smog and I know a lot of states in the US don't have to.

[lazybonez]

Ok, this thread is a decade old. But much of it is still applicable. The best option a decade ago was to buy a running donor car for a drivetrain swap. But the only decent donor was a Z28 Camaro or similar. The Mustang 5.0L pushrod V8 is slightly smaller, but in complete form, with water pump, intake and exhaust manifolds, starter, oilpan, motor mounts, etc. it is just as big as a similarly dressed SBC V8. The LSx is just as big. It's decks are as tall as a 351W, which makes a great 392 if you can afford decent heads, Ford never mass-produced any. Max-ported GT40s still don't equal as-cast 906 / 062 Vortecs.
There are no cheap donors worth considering unless you score a 2WD '96-98 C1500 with the L31 and the 4L60E. If you want cheap LSx, the '01-'04 4.8L truck version is the best deal. I got my first one for $300, my second for $350. Both were complete and driveable, with 30-day warranties.
The LSx swap is not cheap, no matter what corners you cut, it can't be done for under $1,000.00. The L31 can. The L31 will like a cruise RPM of 1800-1900 at 65 MPH, and then can top 25 MPG. For best acceleration with 25.7" tires, the L31 / 4L60E will like a 3.73:1 rear at most, even with porting, cam, headers, etc. If you change the torque converter, order a 2000-stall for a cruiser, or a 2400 for a 3.73 rear. The 4.8 likes a little more gear and a little more stall.
IDK what oil pan will fit best, but you can get front-sump setups for either GM, the SBF is already front sump, the Mustangs were double-sump, with the main one rearward, but the GM's are really rear-sump. LSx is cheapest and easiest to dry-sump correctly for road-race / autocross.

[JBasham]

And most importantly, if you use the Ford 302, EVERYBODY, even people who have never swapped a motor in their lives, will ask you why you didn't do the LS.