Diff - 97-99 M3 is the same part, 3.23 or 3.38, legal. 25% lock, good inexpensive alternitive to a custom diff.

Exhaust - we will have a used Borla trade-in in a few weeks for about $600, used 4 months, manifolds back. Cheap manifolds are 96-99 M3 ($250?). Euro M3 maniflods are good, I should have a used set for about $700. The hot setup is our new custom exhaust, $2-2.5k for headers and full exhaust, 10-20 Hp at the wheels over a Supersprint header/full race exhaust.

I would do either the cast manifolds and Borla or new system. Anything in between is money better spent elsewhere, especially if you are trying to limit money spent twice in future upgrades.

James

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James Clay
http://www.bimmerworld.com
Engineered BMW Performance
World Challenge/SCCA/BMWCCA Racecar Rental
Genuine OEM and Used BMW Parts
(540) 639-9648
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