Suggestions on performance upgrades for 225

Your van is beautiful! Congratulations. Go to slantsix.org and check out Dadtruck's build. He did extensive research and testing before building his truck slant. I think he has the cam for you. Hi compression is a big help for these engines. Again check out Dadtruck's build. I think he shot for 9.0:1 DCR.

Clifford has not been able to supply parts reliably ever since the founding Clifford was gone. Somehow I got a Clifford intake, but no longer remember how. I have Dutra duals, which work well. If you have the low mounted truck starter motor, two will fit nicely. If you have the high mounted, car starter, then the mini started, plus some good pipe bending is required. The original design for the Dutra set up called for cutting the front half off the stock exhaust manifold and retaining the rear section with heat for the carb. This will only work with a stock type intake designed to work with the stock exhaust manifold. Since my slant has MPI fuel injection, carb heat is not needed, but if it gets much below 40f, you will enjoy having it.

I loved my stock Mopar Super Six two barrel. It ran better, and improved mileage over the STOCK one barrel. Keep in mind there were at least three stock one barrel carbs. The two barrel does not increase torgue but adds rpm. The stock 1 barrel pretty much runs out of steam at 4000 rpm. The 2 barrel makes it practical to push the rom to 5000 rpm. I had the Carter BBD. Mine had adjustable power rods, which I liked. The most powerful 2 bbl I tried was an old Stromberg from a poly 318, but it cut the milleage from 21 average to 15.

Guys who are building race engines go with high compression, big cams, big valves, and serious porting. I do not think this is consistent with your goals.

Most of the advice given here was good. One thing to check out is the wiring. The Mopar design allows for serious voltage drop from old bulkhead connectors, old wire, bad ameters and bad crimp connectors. Start the van, check the volts at the alternator out-put and then check it on the high side of the ballast resistor. If you see more than .5 volts drop, there is much performance being lost. I must add, it is more dramatic with electronic ignition. The old points did not seem to care as much. In any event, improving the wiring is cheap, and easy to due.

I must agree with those who said a V8 is easier and cheaper. But the slant is still cool.

Good luck with this and do check out Dadtruck' build.

Sam