If you want to get 300 ponies out of your engine eventually then don't get 1 1/2". If the loss of low end torque is something you can't live with until you get a set of heads and an intake then wait on the exhaust. Or you could have your stock heads ported for a cheap alternative. But your intake will still be the most restrictive part on the engine, so you may want to get that taken care of first too.
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90 Mustang LX 5.0
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