New Edelbrock STR-11 Crossram

If you want to have one that will run as well as a single carb intake just run a pair of Holley 390s.  If you don't mind fiddling with the carb jets, accelerator pumps and squirters, you can run a set of 450s.  If you put enough go fast stuff in the rest of the engine I imagine a pair of 600s would work OK but that is a lot carb for most street setups.  

Sorry you don't want to hear it but we have built multiple crossram engines with the same results and with ZERO modification to the intakes.   

Both engines I'll be running these on are in the 550- 600 HP range with O- ringed cylinders & ported & flowed heads, big cams, good rods, forged pistons, gear drives, etc. I've run the UltrrRam on both w/660 Center squirters & great results. I'm planning on using my original '69 STR on my '69 Nostalgia SS/AMX & already have most of the pieces to make a pretty authentic clone. It was originally a BBO 390 auto but previous owner back halved it & ran NHRA "HotRod" class at 9.80s at Milan the title is still in previous racer's name but I haven't seen that in a decade or more. I sold the original front bumper with molding with a BBO 290 4-speed from Jersey I returned to stock while keeping the 518HP dynoed at the wheels 390, DNE 5 speed, disk rear, & LOTS of MSD, etc parts. I had planned on keeping it orange but it's never gonna be back to stock unless I replace the floors & wheel housings. The factory team RWB looks SO much better, so that's where I'm going. I figured I'll put a piece of tape near the driver door data plate that will stay orange in case anyone in the future wants "proof". Anyway, I've got my "blow off" mod planned to machine into 2" carb spacers so I won't have to hack the vintage nor the new one. The new one will likely go on my 71 that was to be a vintage TransAm play toy until I found out that ONLY cars with verifyable SCCA credentials can run that class. Plan B, NHRA. The 11.5-1 401 w/O-ringed cylinders & ported heads is all together & bolted to the Chevy pattern Richmond 4+1, SFI parts from crank back. I really wanted to road race this & now, if I do drag it, the model 20 with MW axles, Moroso Brute Force posi, & rear disks will have to come out. The last time I tried to drag this rear w/DNE Street5 I didn't move one inch, the itsy bitsy yoke broke off of the pinion & I haven't found any better yoke. If I did, what breaks next? The pinion shaft? I was expecting at least a low 11, if not in to the tens. That was with the 518HP to the rears 390 & 10.5" slicks. This 390 was built out East at Motion, the ports all have stamped numbers, so I know ithey were flowed. That was 518 with a Torker & Carb Shop 850 flowed to 900 CFM.With stock valves. I have 2.08 & 1.74 undercut, swirl polished Stainless valves to go in, Total Seal gapless rings & 12.2-1TRWs to replace the reverse domed pistons it had. H-