Mazda 2.3 DISI MZR Spun Rod Bearing Advice

[PAoutdoorsman]

Originally Posted By: vaboom123
Another thing to look into if you go forward with the build would be tuning options. These cars really need a quality aftermarket tune for longevity. It seems like the speed6's are really plagued with motor issues. From my understanding a big killer is a long highway drive and then heavy throttle to pass or similar situation.

Also I believe engines from Mazda are about $3500 or there's other options out there like CP-E that have short blocks.

Either way good luck with your adventure! They are very cool cars.


Are you saying the factory tuning has issues, or that some of the available aftermarket tunes/tuning are the issue? I guess I have no way to really determine what tuning the car currently has.

 

[PAoutdoorsman]

Originally Posted By: The_Eric
Trav's way is the best way, but it will live a long life if you don't find any obvious problems after a close inspection.

First off, the crank is done. You don't munch a bearing like that and get away with re-using the crank (not long term). Send it off and have it re-hab'ed. Before you do though, pull the remaining rods/pistons and spin the crank in the mains. Does it "feel" smooth? Even, no catches or roughness? Remove the crank and VERY CLOSELY inspect the journals and bearings. Look for even wear on all surfaces.


The crank does feel smooth in the mains. If it has to come out based on what I found with the rod journal on #1, I'll have to pull the motor. It's still in the car.

 

[MCompact]

Originally Posted By: PAoutdoorsman

Are you saying the factory tuning has issues, or that some of the available aftermarket tunes/tuning are the issue? I guess I have no way to really determine what tuning the car currently has.


My 2007 MS3 survived until 136k miles on the stock tune, at which point I installed a Hypertech Sport Tuner. Now at 158k it has never had an internal engine issue- save for a Variable Valve Timing actuator that was replaced under warranty per a Mazda TSB.

 

[vaboom123]

I also have a ms3 with about 100k miles. They are just really hit and miss for engine longevity. Like MCompact said his higher mileage car is doing great. Some others live a short life. I'm purchasing a Cobb accessport to tune with and monitor knock which these cars are sensitive to. I think that would be the best thing to monitor when driving these.

I'm sure it all comes down to how a lot of these cars were driven/modified with the motor issues. Mine has been great

 

[eddy21]

I saw a article on how accelerating at low RPM's can kill the bottom end of these engines.

http://stratifiedauto.com/blog/low-speed...coboost-motors/