A 24-valve M20

[TobyB]

There was a BMW production prototype for a 4v head for the M10 in the early 70's.
BMW decided that it would be too expensive and too hard to maintain (i.e. warranty).

The M12 4v M10 racing head's not all that uncommon in a Chevron, March, etc sports
racer from the early 70's.

Alpina did a 4 valve head for the M10, too, and Alpina and BMW got along pretty well.

Well, then there's the S14, too. Oh, and the first M42's showed up in ROW in the late '80's.

So BMW was no stranger to DOHC, they just didn't see a place for it in a production
car until the 'gas crisis' blew over.

So really, while it would be cooler than shit to bolt a 24v head (and pistons) onto an
M20, it certainly can't be cost- effective, seeing as an M5x can be had (with a whole
donor car wrapped around it) for a couple grand. AND the M20 bottom end's not really
that different than an M5x anyway.

Historically cool, sure!

t

[fporro]

It's my understanding that 24v m20 heads went from Callaway's shop to Racing Dynamics, once there Federico's team took a shot at them as a few critical issues remained, project ran out of time due to m50 engines.

As far as bringing them back from the grave ... RD would do it, but whom's pledging 250k's to get project started ?

Group buy ? $ 2,500 each x 100 heads = much happiness :)

[Vin-barrett]

Eh ludicrous is a strong word. But it's not out of the ordinary for companies to buy out the technology of other companies, or even buying up entire companies for that purpose.

While it may sound reasonable you have to understand Germans are not.
From experience I will tell you there is no way in hell that in those days BMW would adopt Callaways design.

Never mind a cylinder head, If the Germans gave a $hit your E30 would have come with a cupholder....

[dougie30]

I live right down the road from where he blew up the quatros engine ahaha

My dream is to find one of these in some old woman's garage somewhere in the back woods of ct

[Alex Mc]

I want a 12v head for an M50 now.

HA! That made my morning!

Bending valves depends whether the engine is "intereference" or "non-interference" and this is a fuction of lift, duration, piston design, CR... not as simple as how many valves are in each hole.

[bimma360]

in its hey day the quadro would be some premium over a 325i executive so i doubt they had any interest stopping it due to competition or other reasons. i really doubt there is anything more advanced in it over the older 4V BMW heads since they had a much bigger R&D budget and had racing experience with their design prior to the m50

Hahah, dang it man you are still missing my point.

[slammin.e28]

I want a 12v head for an M50 now.

[jeffnhiscars]

its ludicrous to believe BMW got the M50 head from callaway.

The head, perhaps since this still in the early stages but companies buy R&D from each other all the time. Sometimes they further development to a market ready product, integrate design principals in to their own efforts and yes, sometimes to suppress competition.

Goodyear bought the bus system in Los Angeles so it wouldnt cut in to the demand for passenger car tires and Exxon bought Reliance Electric for their highly efficient capacitor start technology which someone never found its way in to the mainstream.

24v M20 is just more valves to slam into pistons when that belt brakes.

That is all.

Still, pretty neato stuff.

;)

My understanding is that 24V engines have a lot less lift and therefore less likelihood of doing piston damage

[digger]

Don't you really think there is something different from the m50 when you look at this #s brought by the head and a few bolt ons?

“A 24-valve M20
230 HP"

The Johnson Quadros is designed to take advantage of the
latent power of the M-20 engine without a complete
engine exchange or massive modifications. The
four-valve cylinder head is designed for direct installation
on the M-20 engine block. The result is 33% more torque
and horsepower than the stock engine without
compromising overall reliability.

no, the m50 is a mass produced engine designed for different end goal and maximizing performance was not the priority. a 2.8L M52 can easily make more than 230hp if someone bolts on parts performance oriented and it hardly affects driveability / emissions etc and likely a whole lot more refined by whats mentioned in the article.

[gath]

...i really doubt there is anything more advanced in it over the older 4V BMW heads since they had a much bigger R&D budget and had racing experience with their design prior to the m50

Don't you really think there is something different from the m50 when you look at this #s brought by the head and a few bolt ons?

“A 24-valve M20
230 HP"

The Johnson Quadros is designed to take advantage of the
latent power of the M-20 engine without a complete
engine exchange or massive modifications. The
four-valve cylinder head is designed for direct installation
on the M-20 engine block. The result is 33% more torque
and horsepower than the stock engine without
compromising overall reliability.

[dirtrider372]

I wonder what a 24v m20 would sound like? I'm guessing very similar to a m5X/S5X. I think the m20 sounds so much better than the 24v motors, but that's just me.

[digger]

I really wasn't saying that the Quadros was basically an M50 head. If that was the case then yeah we'd be bolting M50 heads in our M20's all day long.

I was basically wondering if there was the possibility that BMW either bought the Quadros for the tech info (that MAY have led to the ultimate creation of the M50 BY BMW), OR that they bought it to keep it off the streets until the next generation 3 series came out.

I'm fixating more so on that second point though. But at the end of the day this is all just a matter of opinion and speculation. I am just wondering why that project was abandoned. According to that article the project would have been finalized by Sept. 1, 1985. That is right at the begining of the e30. These heads could have been available as upgrades to e30's for at least 5 years after that point.

in its hey day the quadro would be some premium over a 325i executive so i doubt they had any interest stopping it due to competition or other reasons. i really doubt there is anything more advanced in it over the older 4V BMW heads since they had a much bigger R&D budget and had racing experience with their design prior to the m50

[bimma360]

it didn't sound like it was a particularly refined setup

im not sure what part you think BMW may have bought? if the M50 head bolted to an M20 block easily then that would atleast be some evidence but it seems like the only common thing between the M50 and Quadros is the number of valves and bore spacing. All the rest was probably common with what BMW had done on the pre M50 4V heads

I really wasn't saying that the Quadros was basically an M50 head. If that was the case then yeah we'd be bolting M50 heads in our M20's all day long.

I was basically wondering if there was the possibility that BMW either bought the Quadros for the tech info (that MAY have led to the ultimate creation of the M50 BY BMW), OR that they bought it to keep it off the streets until the next generation 3 series came out.

I'm fixating more so on that second point though. But at the end of the day this is all just a matter of opinion and speculation. I am just wondering why that project was abandoned. According to that article the project would have been finalized by Sept. 1, 1985. That is right at the begining of the e30. These heads could have been available as upgrades to e30's for at least 5 years after that point.

[digger]

Eh ludicrous is a strong word. But it's not out of the ordinary for companies to buy out the technology of other companies, or even buying up entire companies for that purpose. I'm not saying the Quadros was an M50 head.

And although my initial statement is all speculation I don't think the notion is ludicrous. The Quadros could have been in e30's for 3 or 4 years before BMW basically would have come out with something similar for the e36. Even if they didn't use the tech in creation of the m50, it's not that far fetched to think that they may have just not wanted it to find its way in the m20. Even if it would just have been for the tuner market.

I just find it odd that Callaway went that far into the prototyping phase and that early on, without even a single production run. They had all the resources to manufacture these. You usually don't go into the prototyping phase unless you know that manufacturing is viable. So what changed? Did a new variable increase the cost so much that it wouldn't have been marketable... or?

it didn't sound like it was a particularly refined setup

im not sure what part you think BMW may have bought? if the M50 head bolted to an M20 block easily then that would atleast be some evidence but it seems like the only common thing between the M50 and Quadros is the number of valves and bore spacing. All the rest was probably common with what BMW had done on the pre M50 4V heads

[kickinindian]

all i can say about this is that if anyone produced these