SCCA Auto-X Rules: Read This First, Then Ask Questions
- Thread starter apexlater
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Random question since MSP LSDs like to break. What are the rules concerning replacement of a stock LSD? The LSD in the MSP is mechanical, so would I be able to replace it with a Quaife and still be stock legal? If not and I need to stick with stock, could I replace it with a TIG welded reinforced stock LSD?
1. Same as cover other replacements.
"Except for modifications authorized below, Stock Category cars must be run as specified by the factory with only standard equipment as defined by these Rules. This requirement refers not just to individual parts, but to combinations thereof which would have been ordered together on a specific car."
You might be able to say it falls under.
"Alternate components which are normally expendable and considered replacement parts (e.g., engine and wheel bearings, seals, gaskets, filters, belts, bolts, bulbs, batteries, brake rotors, clutch discs, pressure plates, suspension bushings, drivetrain mounts, etc.) may be used provided they are essentially identical to the standard parts (e.g. have the same type, size, hardness, weight, material etc.), are used in the same location, and provide no performance benefit. The allowance for use of such replacements does not include camshafts, differential covers, or ring-and-pinion sets, nor does it authorize the use of piston rings having different configurations (e.g. Total Seal) from those of the original."
2. No
3. Technically no since it is not stock and there is no rule letting you weld to reinforce stock parts that might fail.
From what I have read the latest revisions (legal under stock rules) are not failing like the old ones were.
Since the revised LSD is a superseded part, then yes, you can replace it with the new one and still be legal (same goes for the alignment eccentric bolts on the miata, for example. The old ones tend to strip out, the new ones don't). Any other LSD is out however (quaife, opm, etc). The only thing I don't know is if there are any differences between the original MPS LSD and the revised version other than it being welded more solidly. If there are, I don't know how legal welding yours would be.
I tend to keep to the "if it doesn't say you can, then you can't" letter of the rules
Indeed. That is the easiest, or at least safest way to 'interpret' the rulebook.
