1969 Dodge Dart Custom Sedan Slant Six, Father-Son Project

Putting on non-factory intake and exhaust manifolds means that, well, things probably won't fit right away. Time to do some fit-checking!

The Dutra Dual exhaust manifolds are excellent castings, and the only thing needed to accommodate them was to slightly grind off a triangular (or rather, tetrahedral) wedge off the rear top of the block (circled in blue). Easy. (We were really glad to hear that those are still available to buy!)

This motor is going to be a low/mid RPM torque-monster, so the research led to the AussieSpeed long-runner, 2-barrel manifold. With EFI on the way, we don't care about warming up the intake and carburetor any more, so this was a pretty easy choice (although I'll be curious to see how well the power brake retrofit kit works with this - I hope there's room!). Plus, buying it off eBay provided the latitude of the 'make an offer' option, which allowed us to get this at a deep discount.

Bolting the two, er, three manifolds to the block was very revealing. The casting seam of the intake manifold showed interference with the Dutra manifolds in 3 places. One such place is circled in yellow. Out comes the grinder again.

Also, the central top hole of the intake manifold needed material removed to be able to fully seat the washer that goes on top of that top center stud.

No big deal. But glad we checked this out while it was still on an engine stand.