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 accelerator pump cam to a blue cam and change 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 all mechanical advance.(Never did like vacuum advance). It's using 1.6 roller rockers from Comp. Eng. and a 280H 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 sharp as a razor blade with No flat spots, No bogs, No plug fouling.....nothing.

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[TheRoguelement]

The motor sounds sweet but please can you help Me to understand how an 11:0 ,406 inch motor with AFR 227s in a 3500 LBS Approx car at WOT has certain fuel / Air needs for it to make power .. How does the lil 390 twins supply the above mentioned flowing just 780 CFMs of air ...I'm dupped ??? I realize the NASCAR restrictor plate boys do it with 358 inches or did you make up for all that with jetting and the fact your using twins ? very Nice engineering !!!

[lg1969chevelle]

@TheRoguelement Let me ask you, If you build a 406 using a single plain manifold and and single Quad carb. What carb would you use. Most guys would use 750-780 cfm.

Manifold does not care how many carbs you use as long you have the right amount of cfm.It depend what is the max RPM limit you are running. In my case mine leveled at 6500RPM. If you calculate it's only 700 CFM.

[squafdonoboles]

I found it! Thanks.

[lg1969chevelle]

@squafdonoboles

?????

[Starkster50]

Aim not a big fan of the Magnum Cams but is a awesome combo. I want to put it in my jeep tj but I don't think the front wheels will stay on the ground.

[lg1969chevelle]

@kenzo5716 Thanks, glad you enjoy the video. I have the Chevelle on the road now ever since I had the exhaust system done. I'm having a blast with the Tunnel Ram setup. The Chevelle goes piratically sideways every time I hit the gas pedal right off idle. Your setup is close to mine. IMHO: I Think you are be better off using two Holley 390 #8007. Two 390 on a tunnel ram is the same as one 780 on single plain manifold. It's been done. You get better low to midrange torque.

[kenzo5716]

@kenzo5716 correction, i meant to say "3000 stall" converter.

[kenzo5716]

Beautiful engine. I have a 383 stroker with a tunnel ram and adapter for a single 800 Holley dbl pumper. I run an Isky 280 Mega cam with 1.6 rockers on the intake and long tube Hooker headers in a 1985 Silverado w/built turbo 350 and 4:10 gears/ 300 stall converter. Engine pulls extremely hard to 6500. Do you think the engine would put out more power with the dual carb set-up? I have heard both ways, but was wondering what your opinion is. Thanks for a great video and any advice you might offer.

[lg1969chevelle]

@Halejon1234 Thanks, glad you liked it

[Halejon1234]

So cool, sounds Great!