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Old 12-17-2013, 01:07 AM   #1
Hates Low RPM !
Rob43's Avatar
Join Date: Oct 2009
Location: Richmond VA
Posts: 6,032
My Ride: 03 331Ci 5spd R1200R
SpecE46: Harmonic Time Bomb Disaster

First I want to say I love the idea of this SpecE46 class, and big thanks to Jason Tower & James Clay for getting this going.

As a racer (SCCA) I have a few different concerns on a few things, but one major concern in particular; Harmonic Oil Pump Failure. I believe the first year or two will be a Very Expensive learning curve for both the racers & promoters in this new class.

From personal experience I can tell you that the aluminum block M54B30 is NOT well suited to long duration RPM pulls down a straight away in stock (SpecE46) trim as the current rule book is written. There is a well known & documented high RPM issue concerning Harmonics & Oil Pump Failure in the M54B30, that mostly happens in the 6700 to 6800 RPM range. This Harmonic OPF is greatly exacerbated by three (3) different issues.

1) A light weight flywheel & clutch, instead of the stock 38.5lbs (heavy) Dual mass flywheel & clutch. (the stock dual mass flywheel acts as an Extra Damper on the back of the motor)
2) Any ECU "tune" that extends RPM past the stock 6500 RPM limit. Namely a tune that goes to 6800 to 7200 RPM.
3) Any race track with a long straight away that allows the motor to sustain the dangerous 6700 to 6800 RPM Harmonic failure range. Typically multiple 8 to 12 second (or more) pulls in any gear, (namely 4th) that allows the motor to "stay" in this dangerous 6700-6800 harmonic window.

As the rulebook is currently written, the SpecE46 race community will probably see many Harmonically caused OPF engine failures.

"Specifications & Rules"

Engine: Stock M54 motor, "flywheel and clutch may be upgraded". This rule should be changed to: Stock flywheel & clutch.

"A custom ECU tune may be specified in order to ensure compliance and maximize power/reliability." This rule should be changed to either: 1) A stock ECU must be used with NO tuning software.
Or 2) A custom "Tune" may be used, but with a Maximum 6500 RPM limit.

I would Strongly suggest a change to the rulebook allowing the use of either or both:
1) An upgraded oil pump, in the stock location.
2) The use of an upgraded engine balancer.

The money that would've been spent on a LTW Flywheel & Clutch, and the money that would've been spent on the ECU "Tune" would be much better spent on the upgraded Oil Pump & Engine Balancer. This change in thinking will not only provide the SpecE46 racer with a more sustainable motor, but will provide a more level playing field for every entrant. That of course is because the "guy" with the biggest bank account will be able to afford a custom Ultra LTW Flywheel & Clutch, not to mention the use of a "Super Tuner" that can extract every last ounce power out of his motor, any cost.

Some things for SpecE46 to consider.......

Good luck,

(DynoDynamics Dyno Video)
"Chance Favors The Prepared Mind"

Need Help With Your Nitrous Ambitions ?.....PM ME
Originally Posted by RacerX View Post
Nitrous is a little trickier than boost, but it's not the spray that kills motors, it's STUPIDITY!!

Last edited by Rob43; 04-11-2014 at 02:41 PM. Reason: Auto-save 1397245314
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