[HWYSTR455]

The issues with hydra boost is that you loose a lot of pedal 'feel', and pedal granularity. In a lot of cases it 'over boosts' too.

There's a cost association with using one too, not to mention additional troubleshooting overhead, cost, and increased potential of failures. (more moving parts)

The only reason to use a hydra boost is if you have no other choice, like with boost. That's why the Buick GNs got them.

You're far from no other choice, and a dual 9" booster is your best bet. Don't throw stuff on there 'just because'. A dual 9" works to almost 9-10" of vacuum, and I suspect you will be well above that.

My daughter's 442 has like 12-13" at best, and the assist from a dual 9" is almost too much. It's like a Caddy from the early 70s, will throw you through the windshield if you're not expecting it.

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