Hello All, a question for the brains trust.

How many different bolt patterns are there for the Indy Tunnel Ram intake manifolds? So far I have encountered two. I did a new top for a Hemi version recently, it was longer than the RB Wedge intake I did about 10 years ago. A few people on the board have mentioned that there are a few variations.

Thanks in advance

I made my own top with anti reversion plates and also a white nylon spacer. I made several spacers to play with plenum volumes. It didn't seem to matter. The intake is tall enough already. It does seem to help keep the carbs much cooler even by touch is noticeable.

As far as I can find out there are only 2 Indy T/R available for the R/B. The newer type has 12 bolts (as per your photo's) I can't recall if the older type has more or less bolts but the question has been asked before and a search may reveal the answer.

Has anyone ever done a single 4500 top plate on a tunnel ram

Any results for a 4500 single

I made one with a Single 4500 flange. Never did a dyno comparison. I just decided that a Hemi has to have dual four barrels.

My old school low deck Indy t ram uses 20 #10 screws to fasten the lid. The later versions, IIRC, used 14 1/4" fasteners.

Likely to have mixture issues with a single TR.

I bought an older Indy Tunnel Ram that was like that. I compared it to a later model one & think the plenum design looked better. I ended up converting it to EFI. Sure does get some looks.

That CNC dual TR top is very nice, But I question its design, other than maybe weight considerations, and all the creativity CNC allows, I wonder why the underside does not take into consideration a gentler air flow path, maybe like a tapered card spacer does on the underside. especially in regards to its sidewalls.?

Wel since it is for an EFI system nothing under it really matters. It is a DRY intake and I see nothing wrong with the undersaide of the top what so ever.

Well. it's a fact moving air (wet or dry) likes to stay in motion and transitions are best when gentle as possible, and that is not the case with that TR top.

And having been down this road I see ZERO issues with it. I prefer to work from practice not theory. When it comes to carbs and wet intakes with a carb you woudl want to see a shear plate that protrudes into the plenum, the bottom the intake will affect nothing.

I thought the opening pic here was of an EFI application, my bad.

Thanks for the pic Rebel, the older style is obviously very different to the current stuff.

JCC, I'm with Al on this, I go with what I know works and what I test, not what I think will work.

Cheers all.

There are drag racing classes filled with intakes like this, they're not that much more down on power, compared to dual carbs. They're better than a cast single 4 barrel intake in most cases.

Sorry I haven't logged-in in a while to add anything but as you see there are probably 3 different bolt patterns (possibly more) but the castings I've seen in the last 10+ years have carried the same pattern. I personally don't think this T/R is a good candidate for a single top. Mainly because air doesn't like to turn more than 12* by the time you made a billet top even somewhat respectful of this the engine CID would have to be BIG and the assembly would be 'ludicrous-tall'. There are some good high-end options for a single-4 RB, probably the best is the 3x.