The V8 Owners Forum -

OK so I have changed the gaskets on my SBC and I still get a slight whistle under load, I have used the brake cleaner trick and cannot find any leaks in the inlet manifold but that whistle is still there.

What other tricks are there for detecting inlet manifld leaks, ideally is there something I can use to "pressurise" the inlet side and see if anything is leaking?

easy start is a good spray to use, better than brake cleaner IMO..

The modern test is via a smoke machine, but these are very expensive for a single job.

Basically you pump smoke into the intake and see if there are any leaks.

For a proper test on an intake though, you really need to close all intake valves ( ie remove rockers ) and then you can make something up to try and test with as no air can escape into the cylinders

Mmmm maybe I can find another use for a CO2 fire extinguisher then