Tunnel Ram 406 sbc crank start
406 sbc in a 69 Chevelle. With AFR227 heads using on a tunnel ram setup. Just finished putting it together. I'm running the engine with open headers. Soon it will be on the road.
The manifold is an Edelbrock TR1X, with a pair of modified Holley 390 vacuum secondary mounted sideways. Each Holley 390's were changed from a single feed to a dual feed setup, and replace the secondary metering plate to a metering block from a pair of old 780 Holley. I also had to increase the size of jets on the pri and on the sec. It was running a little lean. I replace the accelerator pump cam to a blue cam and changed it to a #2 setting, and the squirter size was never changed. I'm using an electric choke on the rear carburetor for easy start. The choke assembly on the front carb was removed for clearance. The linkage setup I got is from Holley. I added a balance line for uniform secondary operation. The distributor I'm using is a non-vacuum advance, 100% mechanical. (Never did like vacuum advance). It's using 1.6 roller rockers from Comp. Eng., Chromemoly push rods, and a 280HFT cam from Comp. Cam and it is gear driven . The 406 has 11:1 compression forge pistons with 5.7" connecting rods. I had this tunnel ram setup for over 30 years. I had this same setup on 311 sbc (307 bored 30 over), on my 355 sbc, and now my 406 sbc. Throttle response is as sharp as a razor blade with No flat spots, No bogs, No plug fouling.....nothing.
Built 327 Chevy
1964 small journal two bolt mains. Bored 0.30. Flat top pistons, 2.02/1.6
world sportsman 2 cast heads, 1.6 flat tappet rockers, 284/296 comp xtreme
energy hydraulic flat tappet cam. Weiand tunnel ram and two holley 650cfm
carbs. Timing set at zero degrees
Dads Camaro With Tunnel Ram
Tunnel ram tuning
I had a very large bog off the line that was killing my 60' times which
have dropped from a best of 1.46 to 1.65. Tuning out a flat spot on my
tunnel ram fitted with 660 holleys , home made pump cams, drilled shooters.
Nearly there but not quite.
74 pro street nova 383 tunnel ram idle and walk around
74 nova with a 72 front end' 383 11.1 comp' tunnel ram' 350 turbo trans' 3500 stall' 12 bolt 4.11 rear