That Eddy tunnel ram looks awesome and I have coveted it many times. Love how it is setup for port EFI already. I would love to run tunnel rams on my refreshed 502 if I stay NA.....but by the time you buy that pricey Eddy tunnel ram, top plate, two billet TB's, and fuel rails.....you could have just bought superchargers (used at least) and be done with it! Only thing I worry about with that is those ports look to have a mighty large CSA and would be lazy on a 502 or not match well with 320 heads.

Have y'all seen the new Holley Sniper sheet metal manifolds? They have one for BBC. Looks promising for marine, just wish they had an EFI version. Large plenum and even length runners.....They have plethora of single and dual 5150/4500 mounting options. Price is actually reasonable too, $470.
https://www.holley.com/products/inta...s/parts/835162

Hope they are better than the fabricated one's for the small blocks. I think a donkey had sex with a chinaman and the mutant chinesedonkey kid designed and made it.

https://images.holley.com/825011_01.jpg

LOL....^^^^^^ what a turd

Thats pretty interesting. I’ve been toggling between getting a Victor jr or RPM air gap, and this could be interesting. I doubt that they have an oval port version though.

Have not seen that one yet. I stopped looking as soon as I went and picked up my blowers from Dennis r but prior to then I was all over with my builds. You have no idea how many times I tried to sleep at night and all that would be on my mind was carbs, intakes, tunnel rams and blowers as well as 540-565. I without a doubt woulda stayed NA if my boat didn't weight near 10k. Still hoping I went the right direction.

Is there any any talk on any of the other forums on this one. Your right the price isn't bad at all. I was looking the dart and profiler. Both pricey but good. I don't even wanna think about how confused I was at the time. Newer edel evidently good results also.

I ended up less ci due to going the blower route otherwise I woulda went 565 with TR.

SB your spot on. Lol....

what rpm you going after?

Runners are too short - not a tunnel ram.

Not a tunnel ram but I'd put it in a in btwn category. Equal runner length with two 4150's would be fun to try. Most single planes runners suck. Ideally longer the better however height comes into play with most real TR's. The best single plane I've seen is the brodix sr20. Tall deck one.

I haven't been on holleys sight in a while but looks like their either spending some R&D time to to keep up with the competition or just making some slight changes to the little China men's and having them build to their specs and shipped over. Lol..

I'd suspect the latter haha. From what I can see, looks like they still have the original Holley/Weiand stuff at more expensive prices, then the new Sniper line of I would assume Chinesium parts that pass their quality control.

Funny thing is, they are now selling the 102mm LS TB's that are all over ebay with only their logo on them. Looks identical otherwise right down to the thick throttle blade and fat shaft which disrupts major airflow. I bought one last spring and a 4500 to LS adapter elbow and we put it on Articfriend's chinesium intake 548 dyno mule motor. Norm even reworked it majorly as stock wouldn't even flow over 900 cfm on his flow bench. Killed significant HP over the chinese 4500 flange TB.

I do like the looks of the Edelbrock Pro-Flo XT intake, however I think the 92mm TB opening would be limiting factor......and a proper 102-105mm monoblade TB that actually flows is as expensive as a good 4500 flange TB anymore.

Now, if a TPiS Aqua Lung TB could bolt on the front of the Pro-Flo I'd think you'd have something there.

No matter what way you look at it, it's expensive haha!

Couldn't agree more and noticed the same info you stated. I got to reading the LS guys forum last night. Fun to catch up on everything right now. Seems like so much is changing.

I just wish some more of the new products and technology that has come about from the LS world would trickle down and be adapted to Big blocks a bit faster. Most of the products for BBC have either been out for decades with very little changes, or are meant to be retro or nostalgic versus being cutting edge and no compromises for power.

But then again, it is a very small market for advanced big block stuff anymore, every Tom, Dick and Harry are doing LS swaps, cant blame the manufacturers for going after the largest market.

That's why many of us just stay old school builds. I still kinda wish I woulda went TR. Like you mentioned though you can find good used SC and carbs for price of new TR set up. Still wanna build one some day when I grow up. Where the SC gets you is all the accessories BS to accommodate the blower.

Never really thought about it much but your right. Other than marine there's not a lot of BBC hobbies. Mud trucks and pulling, monster trucks but many hobbies are going by the way side it seems anyway, drag racing etc. Mercury racing certainly didn't hold back on R&D but.... $$$$$. Not for my budget. Lol

Back to the tunnel ram deal, I have played with several, seems to what happened, early large plenum ones worked pretty well on boats, ran a couple, then as tech in drag racing progressed and the RPM's went into the twilight zone thats where the manifold went as well, small plenums, shorter runners etc, those mover the power band up higher than most boats like. they even made some "street tunnel rams" and seemed they would work great in boats although I never ran one, but looked like they dusted off the older designs and made it new again. I have seen many use them with EFI and seems like they work well, on that if you did the injectors down at the ports like new stuff and did the TB's might be the ticket..

I think it would be interesting to take one of the old school Weiand tunnel rams that are of a two piece design, convert to port EFI injection, and throw on the dyno. One could really test that design and the effect of runner length by stacking the 1/2" thick phenolic spacers that they make to change the runner lengths. Would be as easy on he dyno as swapping carb spacers really.

Attachment 572755Attachment 572756Attachment 572757
I use these with good results. We bore out and use the 525 throttle blade. For tuning we use different size stuffers to lengthen the runners and shrink the plenum.

That's a nice looking piece. Who makes it?

Hogan

Kwright can you please explain "different size stuffers and Lengthen the runners"? What kind of stuffers?

Stuffers are plates that bolt inside the plenum. They lengthen the runners and also make the plenum smaller at the same time. It allows you to taylor your torque cure to where you want it.

Got it. So you remove that front plate and they slide in there?

I see the ls ports are above the plenum a couples inches out of the box. Be nice if they had interlocking stackable runners (for inside plenum) in 1/4-1/2 thickness to make it easy to tune "or stuffers". That was a new one for me as well. Lol...

Your head guy JIM V has been using/making stuffers for ever....intake and exhaust ports :) LOL.

But then the LS get's all the cool stuff

How much is one of those for a tall deck.

Awesome!!!

Sometimes we just call it welding. He's raising my floors right now. No stuffers though but ya I know what your refeering to. It's funny I had one of his personal sets of BBC dart cast heads epoxied in 88 or 89.

They fit through the opening. The ports inside are flush with the plenum, the runners are cnced billet so the stuffers can be made to fit precisely over them.

Top mount TBs will always be better if you have the room.

Ive also read sime anecdotes that cast manifolds are usually better than the fabbed ones.

Not always true remember your just flowing air.
the problem with cast ones your stuck with the limitations of the design.

I figured I would pitch in here. Forgive me if I forget some exact details, it has been a while :)

I did a decent amount with tunnel ram's back in the late 70's/early 80's. When I first started with this stuff a big name engine builder did my engines and tried the Weiand's with some spacers. Probably 3" or so. Made great numbers on the dyno but the first time in the boat broke the snouts off both crankshafts! Looking back it was probably due to lousy distribution but what did we know about that back then? So much for the big name engine builder.

So - I decided I could do no worse on my own. Moving on I was lucky to hook up with a local shop (Pro Motor) that had a good reputation and one of the few dyno's around Chicago. And more importantly Peter (the boss) went along with some of my ideas. We built some 540 inch motors with Rehr Morrison heads. Pro did the machine work and I did the assembly.

At the time I also had a great relationship with the local warehouse distributor. The WD was nice enough to loan me a couple of manifolds, tops, Dominator's, and 780's. Tried single 1050's, dual 1050's, dual 780's and a single plane 1050.

Edlelbrock Victor was the best. Back to back - the Victor w/780's made more torque and power than the 1050's. I don't remember the exact number but I think after some cam swaps and tweaking we wound up close to 800 HP @ 6000 RPM.

These engines were rebuilt once a year every fall. And every rebuild they went on the dyno. Always looking for more power I kept trying new stuff. Carl Foltz (CFE) was just starting out at the time. Carl did the intakes for me and BAM - more power. Did some bigger carbs with side inlet bowls to fit the manifold - more power. Better oil pan - more power. At the end had about 850 hp.

In regard to the original post - hell yes to tunnel ram's. I would never do carbs again, EFI for sure.

Here is a picture of the Weiand, looks like the spacer was not as big as I remembered. Bottom line - it didn't work :(

Marc,

Thanks for that. Pro Motor, did that have something to do with Gary Stuwe?

Jeff

I think that at one point Gary was involved. If I remember correctly he was out of there by the time I hooked up with Peter.