E46 M3 advice

[dillonmo]

Morning Fanatics,

I’m finally looking at purchasing an E46 M3. Came across one for 279k. High miler(199k). Going to view it this weekend. Judging from the pics, car looks original. Been reading a lot on this forum about maintenance of this car. One area of concern for me, is that the engine was redone and has had a 20thou rebore (orig bore 87mm, now 87.5mm). The work was carried out at Savspeed. I don’t intend tracking the car (or doing donuts 😬). Just want to enjoy this model M with the occasional spirited driving. Could this rebore be a recipe for disaster? If not, would the quality of the work by Savspeed be an issue? (read good and bad things about Savspeed - as with any other workshop). What are some of the questions I should be asking regarding this engine repair?

Thanks Dillon

 

[Peter@AEW]

If the engine bolts are not worth cleaning what else has not been cleaned prior to assembly or during assembly?

When building an engine "clean" and "attention to detail" is paramount.
Main caps bolts are being re used and should be new as they are stretch bolts and once used they should not be re used.
Guide rail has been left dirty.

 

[individj]

hhhmmmmmm think you have your answer

 

[Peter@AEW]

Haxor's engine after complete overhaul.

 

[shauwn]

Haxor's engine after complete overhaul.

now thats clean overhaul !!!

 

[shauwn]

now thats clean overhaul !!!

just for interest, how much would such an overhaul cost peter?

 

[Peter@AEW]

Compare the bolts here with your pics and you will see the difference between new and old.

 

[Peter@AEW]

just for interest, how much would such an overhaul cost peter?

On this engine we had to get a new crank and pistons so it got to roughly 180k.

 

[dillonmo]

Thank you for the feedback Peter. It is much appreciated.

On this engine we had to get a new crank and pistons so it got to roughly 180k.

🤯

 

[Steph745]

Mechanic Tasos Moschatos on YouTube works mainly on Merc M156/157 motors but is always particular about workmanship and cleanliness, you really see why in his engine teardowns after work that was done by other shops. Sure the same applies here. Perhaps previous owner had not wanted to spend the money to 'do it right'. Either way ........

 

[Crash_Nemesis]

My e46 M3 S54 is rebored to 87.5mm. Vac Motorsports recommends this bore is done with a Torque plate as it ensures perfectly cylindrical cylinder walls as the OEM bores from BMW are mass produced and are said to not be 100% round from factory. Fine for street use, but not for race teams. This is the reason for the overbore. All major race teams that run their S54 engines NA use 87.5mm overbore. For street use it is perfectly safe and drives like stock. You may find a slight increase in low down torque but power numbers are roughly the same. I have ran this bore for over 10 years.

Regarding SAVSPEED, I would never send my car there again after the balls up they did on my engine when it went in for valve clearances and a cam change. A retainer clip was not put back and the car dropped a valve 2 days later, thus resulting in a complete rebuild of my engine. SAVSPEED refused to take responsibility for the work as the camshaft was not sourced by them and instead delivered by me, thus putting blame on the camshaft. Again, a retainer clip was missing when we opened the head.

Furthermore, I still run this camshaft in my car 10 years later, so clearly, it wasn't the camshaft. Do what you will with this information.

 

[dillonmo]

Thanks Crash. I lost out on that particular M3. Judging by current e46 M prices, even if I spent another 150k redoing the engine it would have been worth it. That car was in absolutely original condition. No respray to hide stone chips/ scratches etc. a true survivor. Anyway paid a deposit, broke garage walls to accommodate it, owner decided to pull out of the deal. Fml