Family cruising in a cab: 318i or 325i?

[dcdude]

I'm trying to decide between M42 and M20 powered cabs. If it was just me in a lighter coupe, I expect that the performance difference would be more minor, but I'm concerned that if I pile in the wife and two small kids that I might be a bit disappointed with a 318 cabriolet compared to the 325. I won't daily drive it, so the MPG advantage of the M42 doesn't mean much to me. Either car is very likely to be a 5 speed.

Your recommendations? Thanks in advance.

[F34R]

You mean the m42, BMW only made the m10 and m42 for the BMW e30. Since the vert was made in 87 it only came in: m20b25 and m42 base engines.

In 96 the M42 was replaced with the M44. You will want the m20, better power overall. The m42 is not bad, but is not powerful at all. Needs a turbo to be of any use IMO. I have driven the M42 and it was just boring.

M20b25:168hp/164trq(this would be my pick, higher HP and almost b27 trq)

M42b18:134hp/127trq

Edit: I was smoking something strong.

[frankenbeemer]

What are you smoking tonight F34R?

[frankenbeemer]

You mean the m42, BMW only made the m10 and m42 for the BMW e30. Since the vert was made in 87 it only came in: m20b27, SETAm20b25 and m42 base engines.

In 96 the M42 was replaced with the M44. You will want the m20, better power overall. The m42 is not bad, but is not powerful at all. Needs a turbo to be of any use IMO. I have driven the M42 and it was just boring.

M20b27:121hp/170trq

M20b28"aka" SETA(1988 ONLY) 127hp/170trq, with the b25 head, intake and 173 ECU this is the best engine out of the m20

M20b25:168hp/164trq(this would be my pick, higher HP and almost b27 trq)

M42b18:134hp/127trq

Hmmm.

[F34R]

What are you smoking tonight F34R?

I have no clue, my bad lol

[nrubenstein]

Nothing, what is the reason you think so? and you can quote my post and put it into one single one instead of a retarded "hmmm"

He asked what engine would be best from the e30. There is 3 to pick from and one to get lucky finding. Best one out of the bunch is the m20b25 given from the higher HP and almost the same trq as the b27. I answered his question in full, and told him the 4 cylinder history. BMW never made a M45, Infiniti does though ;)

If you mean this:
"M20b28"aka" SETA(1988 ONLY) 127hp/170trq, with the b25 head, intake and 173 ECU this is the best engine out of the m20"

That is not a factory engine, you should know of that simple upgrade by now. Take an afternoon start to finish if you know what you're doing, weekend if you're new to engine tear downs. If you can handle a water pump and timing belt you can do the b25 head/intake upgrade on the ETA engines.

He's asking what you are smoking because BMW never sold the 'vert with any variety of eta engine.

[nrubenstein]

And to the OP: The basic answer is that both of them will be slow. Get whichever one is in the best shape and run with it.

[SpecM]

N
If you mean this:
"M20b28"aka" SETA(1988 ONLY) 127hp/170trq, with the b25 head, intake and 173 ECU this is the best engine out of the m20"

That is not a factory engine, you should know of that simple upgrade by now. Take an afternoon start to finish if you know what you're doing, weekend if you're new to engine tear downs. If you can handle a water pump and timing belt you can do the b25 head/intake upgrade on the ETA engines.

b28? where are you getting this stuff?

[F34R]

He's asking what you are smoking because BMW never sold the 'vert with any variety of eta engine.

Like he said, "what am I smoking", I remember commenting on a 89 vert with a b27 swapped into it. I have no idea why I fucking posted that. I will fix my post to reflect the correct information. Sorry OP, I cannot believe I made an error like that. I even posted the BMW e30 models pricing on my facebook. I typed the 325i in 1987, I had a complete brain fart.

b28? where are you getting this stuff?

I have no fucking clue, from reading on here they have a larger piston. But I am on Strictlyeta.net and the bore and stroke is the same between the ETA and Super ETA. Must be the information I gathered from builds on r3vlimited is wrong.

325e (1984-1987)
ENGINE/TRANSMISSION
M20 2693cc SOHC belt-driven inline 6, 2 valves/cylinder, cast crankshaft
121 hp @ 4250 RPM
170 lb-ft torque @ 3250 RPM
Compression ratio: 9.0:1
Bore/stroke: 84x81 mm
Bosch Motronic 1.0 fuel injection w/ DME
Exhaust control: 3-way catalytic converter with Lambda sensor

325 (1988 "Super Eta")
ENGINE/TRANSMISSION
M20 2693cc SOHC belt-driven inline 6, 2 valves/cylinder, cast crankshaft
128 hp @ 4800 RPM
170 lb-ft torque @ 3200 RPM
Compression ratio: 8.5:1
Bore/stroke: 84x81 mm
Bosch Motronic 1.1 fuel injection w/ DME
Exhaust control: 3-way catalytic converter with Lambda sensor

I know the SETA uses the b27 crank, but I was sure the SETA pistons are larger. Searching...

Super Eta crank and rods are the same as Eta parts. The Super Eta pistons are specific to the Super Eta, and the Super Eta engine uses the 885 head casting.

I will look at the markings on the piston domes when I pull my head on the SETA.

[dcdude]

And to the OP: The basic answer is that both of them will be slow. Get whichever one is in the best shape and run with it.

Thanks guys. Yeah, I'm not expecting "speed" out of either, but struggling is a whole 'nuther thing. Thanks for the input. "Buy the best maintained example" was always our advice with Porsches.

[flyboyx]

something else to think about: the m42 cars all came with vinyl interiors. none of them have cruise control or 13 button obc. all m42's were manuals i am 97% sure.

all m20 cabrios came with leather sport interior, cruise, etc.... but usually came with an auto trans. all this can be retrofitted one way or the other to either car. only the 91's and 92's(93) came with the late style facelift body style which is more desirable.

unfortunately, 91 to 93 m20 cars came with a power top. those are maintenance nighmares.

[scottinAZ]

best answer:

Get a good straight example, and 24v swap it. No lack of power, and a better engine to boot. :D

[dougie30]

325i

[robrez]

I love the m42, but the type of driving you are contemplating will probably not make you a happy person in the m42 cab, ie. extra weight, AC on, shifting at low RPMs, not tossing car around. A 4.45 diff swap might help, unless you plan to do a lot of highway driving.

[Mossman]

If you're gonna leave it stock I actually think I'd take the m42 car. Lighter, more nimble, better mileage, but you really need to ring it out a lot.

When I had both a bone stock 318ic on 14" all seasons and a modded 325ic on koni's, H&R sports and sticky 17's, sometimes I'd prefer to drive the 318. The lack of weight over the front end is really noticeable, and I could take turns almost as quickly despite having a serious grip disadvantage.