My experience shows an over all change when comparing 02 locations. W/02 located on the collector, results are rear cylinders become progressively richer (evidenced by spark plug coloration). W/02 located on #7 cyl. like most headers, there is an opposite effect.
However, when just comparing locations only, tune being the same, when an 02 is being used on the collector an overall leaner BLM happens, and when monitoring w/an 02 on #7, an overall richer BLM occurs.

If you had "control" of each cylinders input via an 02 and an ECM (not stock) that allowed for proportional control, they could feasibly all be tuned the same.

 

Here is the way I see it. If the plenum is at or very close to atmospheric pressure at wide open thottle there is no problem. There is plenty of air for all the cylinders.

If there is a depression in the plenum at WOT then the individual cylinders are fighting for the available air. So IMHO it depends.

 

From I remember about that comparison article/post , I was thinking they siamesed the runners to about the same length and the diameter was about the same as the SR, but It didn't perform as well. That was the puzzle to me, and I figured the difference was in the plenum volume. If they were a different length it would be obvious what the problem was. Have you considered the Edlebrock #29785 single plane?( 4.58" high). They've published the size of their Elbows now; #3847 is 9" long x 3.62" high. That combo might just work under a C4 hood; something to think about anyway.

1989TransAm...I've read your posts on a couple of other sites besides this one, and I know you've put some work into TPI intakes.

 

Corvetteforum + thirdgen.org = same company. We're one big IB family.

The guys you are referring to are a bunch of goons who did nothing bus diss corvetteforum's ownership and management. Good riddance!

Either way, I think most of this was covered a few times. But it's a good discussion, I'm glad folks like mseven jumped in here.

Now that edelbrock makes some really nice 90* elbows that mount to the singleplanes and run a LS style throttle body, I'm kinda kicking myself in the pants for running the miniram. The fastest combos I ever had were with the singleplane intakes and the fastest one I had actually was the one I built using a carbed 'street dominator'. Ugly but it was perfect.

-- Joe

 

I think there is more hype to the miniram then it is worth. I agree that you can run a singleplane cheaper and more effectively then a miniram and get the same if not better results.

 

Well, I look at it this way. Miniram is like an LT1 for sbc. So expect the same performance. It has it's issues (some cyls run lean, etc) but overall it works and fits under the hood. The Superram is just a waste of money, a pain in the *** to work on, and prone to gasket failures.

Singleplane is where the power is at, but it doesn't fit under the stock hood w/out a 90* elbow of sorts.

I went with the miniram because it fit under the hood. Was more expensive than the SR, but is a better intake. On my fbodys I had singleplanes.

I got a few pm's about this post, so I'm gonna paste the PM info here. If it's "off topic" I'm sorry, but a few people are asking about the Singleplane intakes.

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Let's talk elbows first.

The edelbrock 3847 is a low profile (3.5" from flange) designed for high HP applications. It retails at $119,
part # EDL-3847 from summitracing.com. It will mount either a LS1/LS2 style TB, or ford monoblade TB. It has a mount point for cable bracket. If using an LS1 TB with an automatic, you'll have to add a tab for the detent cable. For stick cars it's plug and play, assuming you get the bracket spacing and cable to work propper. Most guys use throttle cables from S10 pickups as they seem to be the 'right length'.

Another option is the ultra low profile box style EDL-3850 (straight forward) or EDL-3851 (side mount), both supporting up to 400hp. The EDL-3851 would be perfect for a supercharged application (and would push that 400hp limit). Both boxes are 1.5" high. The forward mount may have issues with the thermostat, and may require a weiand thermostat housing (designed for blower applications, they move the thermosat forward about 4") or use a 1.5" carb spacer. This will all depend on the intake manifold you use, and what its mounting height is.

For rule of thumb, edelbrock victor EFI (EDL-29786 $400 w/ fuel rails) stand 5.25" high.

Holley (HLY-9901-101-1 $340, fuel rails HLY-9900-172 $225) stands 5.25" high

Accell pro-ram (ACC-74139 $430 w/ rails) stands 4.85" high.

The Victor EFI supports about 400 HP with a 1204 gasket port. The accel and holley both support 500+ hp, the holley being the winner can run a 1206 gasket and support a 700hp SBC. The holley fuel rail kit comes with an adjustable regulator as well, the edelbrock is an extra
cost for the regulator. I can't remember on the Accel.

A stock TPI setup is 9" tall, and is the absolute max working height due to the hood on a corvette. So with those numbers and ideas, you can build a pretty straight forward setup that supports 400-500+ hp for short money, that will fit under the hood.

-- Joe