Lightweight e30, have platform/engine ideas, leaning 318is/N52… talk me out of it

[E30 Wagen]

isn't parts availability the issue with the m42 now? it seems to get cited more and more as the reason for a swap option

Yeah, that's the big problem. If certain parts could be reproduced or substituted then I'm still in the m4x 88mm stroker camp though, just seems easier.

If you're in the market for a nice $10-15k example then indeed you may discover it's plenty fun to drive and the hassle of an engine swap isn't worth it, especially if it's in survivor condition where extensive mods may actually hurt the residual value. Same could be said for a nice 325i. If you can find a nice 325i then that's obviously more power out of the box with straight forward upgrade paths, and it's still going to feel light compared to a newer platform. When it comes to m5x or s5x swaps I'd rather just get an e36 at that point. But the 128i remains a very compelling option as a modern 318is, of course not as light but certainly small and nimble. Get yourself a nice one or two owner slick top 6 speed example now, guaranteed future classic.

[82eye]

the 128i remains a very compelling option as a modern 318is, of course not as light but certainly small and nimble. Get yourself a nice one or two owner slick top 6 speed example now, guaranteed future classic.

i watch the locals daily looking to see if a manual e82 slips through. i truly believe it's the spiritual successor to an e30.

[adam.nonis]

K24 w/ZF: 427lbs




Sent from my iPhone using Tapatalk Pro

[82eye]

wow .. weighs out identical to the m42

[82eye]

Yeah, that's the big problem. If certain parts could be reproduced or substituted then I'm still in the m4x 88mm stroker camp though, just seems easier.

it's a bit sad as bmw has been noted for supporting the older platforms. that is fading for a lot of marques, everything ages out of being financially lucrative.

If you're in the market for a nice $10-15k example then indeed you may discover it's plenty fun to drive and the hassle of an engine swap isn't worth it, especially if it's in survivor condition where extensive mods may actually hurt the residual value. Same could be said for a nice 325i. If you can find a nice 325i then that's obviously more power out of the box with straight forward upgrade paths, and it's still going to feel light compared to a newer platform.

at some point i had to make the call whether my car was going modded or clean. you never see them here, so there was an argument for a clean stock example, but i don't consider it all that rare or special. it's been painted once already, and it's failing. it's getting paint again in the spring. but it won't be showroom either.

since i wanted a driver and it's no collector the decision to have some fun and mod it was easy. i'll never make the money back, but i built most of the drive train with my dad, and i'll never replace that experience.
long term the car will never be worth what it could be as a restored stock example. i've completely capped the value to any future owner. but who cares.

When it comes to m5x or s5x swaps I'd rather just get an e36 at that point. But the 128i remains a very compelling option as a modern 318is, of course not as light but certainly small and nimble. Get yourself a nice one or two owner slick top 6 speed example now, guaranteed future classic.

need another job first lol.

[OSAH racing]

The Value is in the experience. Its always worth the cost if you use it.

[FredK]

If I wanted to make a nice canyon carving E30, I would probably get an M20B25-powered car, grab a used M20 for $500 or less, and build a slightly modified engine for a modest price--maybe around $3500 - 4000 inclusive of machine work for something with new pistons and balancing work. The best modifications will be to replace the suspension bushings and get good dampers and not going crazy with engine mods. I don't want an E30 that goes too fast, as it's not that safe of a car should something go awry.

If "driving a slow car fast" means taking pleasure in a momentum car, having more than say, 200 wtq at your disposal reduces the satisfaction of keeping the car on edge when mistakes can be nearly erased with torque on tap. On the other hand, it is satisfying to have a lightweight car with good power-to-weight.

I think an N52 swap would be a great mix of affordability, power, and reliability. The downside, as you've identified, is that you would have to do some fabrication and wiring. But, there are folks on the N52 subforum who are very knowledgeable and helpful, so if you have that DIY spirit, I think you can get things done.

[varg]

wow .. weighs out identical to the m42

Maybe, if all of the accessories are on the other side. But that M42 weight was wet + all accessories (PS, Alt, AC) and that picture is a dry weight with no visible accessories. Still, it shows the potential of the K24 swap to be lighter than M42 if you keep the same transmission.

[packratbimmer]

Maybe, if all of the accessories are on the other side. But that M42 weight was wet + all accessories (PS, Alt, AC) and that picture is a dry weight with no visible accessories. Still, it shows the potential of the K24 swap to be lighter than M42 if you keep the same transmission.

Agreed: When we are studying these weights online one must also remember that the K engines were bolted to a transaxle which is heavier than the 260 Getrag--for instance.

[Jb325is]

This is a great post, good to see some healthy activity on here.

I agree with most of the sentiments above, I think you're getting some good input here. My personal car went from M20-->M90-->S54-->S50-->M54 and my opinion is that the M54 is a really nice happy medium of power / balance. The M90 was too heavy, the S54 was too much, S50/M54 was just about perfect but the M54 was lighter.

That said, I think the supporting modifications are more important. Any nicely spec'd e30 with high quality dampers, fresh bushings/arms, proper alignment, good tires will provide the experience you're after... My opinion would be to skip the M42.

[2mAn]

Go drive some E30s, that would help the decision making... Where are you located?

[AWDBOB]

Like many, I have been reading the N52 subform for ages when I can't sleep. My perception is that the complications are such that the juice doesn't seem to be worth the squeeze, yet.

I adore the way an M20b25 feels/sounds in a well set up E30.

There are a few affordable M20 stroker motors that you can build if you want a little more, with the bonus of a very simple, fantastic and sounding driving experience.

M52b28 crank 130mm M20b27 rods, late model short skirt 325i pistons, shave deck ~0.5mm to make a 2.8. Sometimes hard to find a b28 crank with small counterweights and have to have them turned to clear piston skirts which can be a pain.

or as I do it since M20b27s are practically given away at this point:

M20b27 crank/rods, late model short skirt 325i pistons, deck shaved 2mm.

Makes a 9.4:1 compression 2.7L, I have been very happy with the few I've done.

I do think as I get older I chase the dragon a bit in finding the "best combo", but the best car seems to be the one that I drive the most. I really think a stock M20b25 car that's well set up, with a pnp standalone and good exhaust as a bonus will get you most of the way there.

I don't love the way 24v engines feel in an E30. All of the 24v swapped cars I've driven haven't influenced me enough to switch away from the M20 platform, but that is purely preference.

[amcp]

Having experience with a 318is M42 slicktop, a bunch of m20s 325s, a S52 swapped cammed 325 and a S54 325, I'll agree the lighter nose on the M42 is a sweet feeling. But the punch of the S54 is addicting. A well setup s52/s50 is a nice middle ground.

[packratbimmer]

Great thread!!! Wouldn't it be great if all the new E30 folks could drive an E30 325i with a perfectly working M20. I think a lot of folks buy a project car and think "ah these M20 engines are horrible - what can I do to upgrade" when they are not taking into account that the engine is tired and out of tune. Obviously, many folks on REV want mucho power, but what I'm saying is that potentially 50% of folks would be psyched with a light 325i and 175 HP.

[hoveringuy]

Great thread!!! Wouldn't it be great if all the new E30 folks could drive an E30 325i with a perfectly working M20. I think a lot of folks buy a project car and think "ah these M20 engines are horrible - what can I do to upgrade" when they are not taking into account that the engine is tired and out of tune. Obviously, many folks on REV want mucho power, but what I'm saying is that potentially 50% of folks would be psyched with a light 325i and 175 HP.

I'm a little nostalgic for the M20, I definitely enjoyed the mechanical character of that engine.

Wouldn't go back to it in a 100 years, I have +110whp with the N52, ZERO leaks, it's lighter and I have a 6-speed, plus my oil pan is higher and more protected. When the engine was running rough INPA told me exactly which coil pack was going bad AND it has really good fuel economy from VVL.