1973 3.0Csi conversion?

[dunromin]

I have a 1973 3.0 Csi that runs great with the original motor and 4 speed manual. It is Fjord blue with blue leather and beautiful wood dash. I really love the car.

I have the opportunity to have my local mechanic put an s52(spelling) motor in my car.
It is an american M3 motor from 97 I believe with less than 45 thousand miles on it.
Questions are these:
Would you remove a perfectly operational 3.0 motor and 4 speed to upgrade?
What does this do to the value of my coupe?
Can our 3.0 chasis' handle M3 torque?

Any applicable comments welcome on the subject.

Matt in Sausalito

 

[OZCSi]

Hi, I have a genuine euro m3 from the same year and even though it cranks out far mnore power than the us version, I wouldnt put it in. It is the wrong style in my opinion for the grand coupe. Like putting a 900cc japanese bike engine in a Harley. Anyway that is my opinion, so I stand ready for criticism.
What you have is great, and rare.

Cheers

 

[dunromin]

Thanks...I dont disagree. Just tempted.

 

[abe3.0CSi]

I leave it alone...if any upgrade it would be to change the transmission to a 5 speed or leave as is.
abe

 

[dunromin]

The transmission is definitly the main goal. What does it cost to execute a proper 5-Speed conversion?
Thanks

 

[Mario L.]

This is seriously the wrong conversion for this car!

Here's why;

We completed the same in a 1987 E28 535i . . which is essentially the same engine compartment as an E9, both being of the M30 engine family.

The S52 although based on the old M20 (528e) engine is hugely different in dimensions than an M30. The cylinderhead takes up a huge amount of space, the only gearbox that can handle the power of the S52 is the E36 M3 5 speed, (also found in other 2.8 liter apps). There are no motor mounts that allow this install to be easily completed. We tried the M20 mounts and any mounting bracket that fastens to the M20 M50 S52 blocks from all chassis. Ultimately we fabricated our own mounts , and used a different oil pan. The engine sits so low that the bottom of the sump is lower than the subframe! We had interference at the top of the transmission tunnel and difficulties with the rear of the transmission. We had exhaust complications with the headers from the S52 around the steering linkage and motor mounts . . the list goes on . ..

Overall, I determined this to be the most complex engine swap I'd ever done!!!

With all the options for engines into an E9, this is seriously not worth the hassles . . . I'd much rather do an S38 3.8 with all the associated plumbing and intake issues vs the S52.

Read the January issue of Hemming's Sports & Exotic Cars for an example of what we can do . . .

 

[CSteve]

My experience for what it's worth says don't do it. I did the easy swap, a 3.3 liter block, 73 reworked CSi head injection, and cam with five speed into my 74 carb euro coupe.
Plenty of power, enough for Driver's Schools, completely stock looking, no radical mods to suspension, steering, oil pans, etc.

Another guy here simply put a five speed into his 74 CSi and loves it.
Bolt on sport springs, beefy sway bars, Koni's or such, headers and exhaust and you will love it.

Steve ONeill 74 CSi

 

[dunromin]

Thanks

Thank you for the feedback, very helpful. I think i will stick with what I have and appreciate it for what it is untill maintanace forces me to answer these questions.

I took her for an early morning drive up Mt. Tamalpais her in Marin County a couple weeks back and it was the best drive of my life...

past rides: 993 Cab, 1989 M6 and 2003 530 Dinan

Still, the E9 is best ride...even without 5th, or even 6th gear

 

[jranmann]

My experience for what it's worth says don't do it. I did the easy swap, a 3.3 liter block, 73 reworked CSi head injection, and cam with five speed into my 74 carb euro coupe.
Plenty of power, enough for Driver's Schools, completely stock looking, no radical mods to suspension, steering, oil pans, etc.

Another guy here simply put a five speed into his 74 CSi and loves it.
Bolt on sport springs, beefy sway bars, Koni's or such, headers and exhaust and you will love it.

Steve ONeill 74 CSi

I agree entirely and the b32 block if fine with a ported head...suspension is key and of course rust prevention.

I took her for an early morning drive up Mt. Tamalpais her in Marin County a couple weeks back and it was the best drive of my life...

Saturday morning I was sitting on the large mostly open front porch of a 1902 massive home on Grand in San Rafael where I had the night before celebrated midnight services at the Lutheran church in Marin and framed within the side windows was the most gorgeous view of Mount Tam framed perfectly within the window muntins which are original to the home's design and flair. What was most interesting (as I live in So. Cal and had seen it only a few times) was how the morning frost had given the peak a real white glow as if covered in fresh show....beautiful!

As a suggestion...where I learned about Mt. Tamalpais was from Alan Watts in his book written entirely there some 45 years ago...perhaps the next time you go up Matt, see if you can locate and take with you a paperback copy of his 'Cloud Hidden, Whereabouts Unknown' and then see if you happen to see and experience what i think I saw up there on Saturday...(as it relates to the his concept of Zen and the Art of e9 Maintenance?)

Cheers!

Ran

 

[chicane]

I have a 1973 3.0 Csi that runs great with the original motor and 4 speed manual. It is Fjord blue with blue leather and beautiful wood dash. I really love the car.

I have the opportunity to have my local mechanic put an s52(spelling) motor in my car.
It is an american M3 motor from 97 I believe with less than 45 thousand miles on it.
Questions are these:
Would you remove a perfectly operational 3.0 motor and 4 speed to upgrade?
What does this do to the value of my coupe?
Can our 3.0 chasis' handle M3 torque?

Any applicable comments welcome on the subject.

Matt in Sausalito

NO! It will ruin the look and feel of your coupe for what 40 more HP?