Test 11: Wilson 1 1/4-Inch Open SpacerWestech told us they've often seen improvements by adding a 1 1/4-inch open carb spacer (PN 000020) to the Air Gap manifold, so we thought we'd give it a try. Our results were not great, and power actually fell off just about everywhere. That probably means that the Air Gap's plenum was large enough for DM, and it didn't need the extra volume a 1-inch spacer added.
Test 12: Comp Cams Xe262h CamTo either prove or disprove our theory on whether or not the engine needed more air to make more power we swapped in the next size larger COMP Cams XE262H Xtreme Energy camshaft (PN 12-238-2). The cam was 6 degrees bigger at 0.050 with 0.015-inch more lift and added a little more top-end power while giving away some low-end grunt. It was kind of a wash, but we think the motor liked the XE256H cam better, and it would definitely have driven better on the street with the extra low-end power of the 256 cam. However, since we plan to test new heads next month, we'll leave the 262 cam in place because it'll probably respond well to the better-breathing heads.
3rd Series Of Dyno TestsWe number each series of tests consecutively, starting with the number after the last of the previous month's tests. We'll also list the last test from the previous month, so you'll have something to compare the new tests to. So this month our first new test is number 9. Unless listed, no other changes were made for any test.
Test 8: Last test from last month. Weiand 8004 intake, COMP Cams 1.5:1 full-roller aluminum rockers, Carb Shop Q-jet, COMP Cams XE256H cam (256/268 adv duration, 212/218 duration @ .050, .447/.454 valve lift, 110 lobe separation, installed 2 degrees advanced), 1 3/4-inch Hooker Super Comp headers and Flowmaster 3 1/2-inch mufflers, 37 degrees total advance.
Test 9: Install Speed Demon 750 carb with 82/88 jets.
Test 10: Install Edelbrock Performer RPM "Air Gap" intake manifold.
Test 11: Install Wilson 1 1/4-inch-tall open aluminum carb spacer.
Test 12: Install COMP Cams XE262H cam (262/270 adv duration, 218/224 duration @ .050, .462/.469 valve lift, 110 lobe separation) straight up.