Tunnel Rams

Discussion in 'High Performance Modifications' started by Appstro, Oct 21, 2009.

  1. Appstro

    Appstro Veteran Member

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    Whats the deal with Tunnel Rams. They look so bitchin' and yet I see nobody running them at the strip or on the street. I see them in boats and thats about it. Does the bottom end just drop off with these things? I really want to put one on my 350 but I am afraid it will just be a dog afterwards. Also what kind of a motor do you need to have to take advantage of a dual high rise?

    On another note how about a dual carb manifold that is not a high rise? Are they any good on a slightly modified 350 or is it overkill? Same issues with low end torque loss?

    I appreciate your opinions and advice, so thanks in advance guys!

    Mike
     
  2. Cardinal

    Cardinal Veteran Member Lifetime Gold Member

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    Tunnel ram intake is a PITA to run. If the engine backfires it usually blows the carbs off the top (unless there is a blowoff plate installed which kills the engine from running at that point).

    Most entry level people don't have the expertise to tune any dual quad intake. It takes a special touch to tune one properly that's why most beginners start with a single quad intake.

    As for "what kind of motor" do you need to take advantage of a tunnel ram? Usually, you find them on big cubic inch or high reving motors that can pull all of that intake volume through them quickly. I've seen them run on the street but again, they're usually a PITA to run and make them run consistantly.
     
  3. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    most tunnel rams like mine are designed to work best from 4000-8000 rpm and yes there not alot of bottom end power but once you're in the powerband hold on because it pulls like crazy !! . most tunnel ram motors like alot of compression , agressive cam profiles that match the tunnel rams powerband and alot of rear gear with a manual trans or loose converters

    my combo is a LT1 350sbc 11.1:1 comp , gm#140 cam 257/269 @ .050 493/512 lift 4200-7200 rpm , ported/polished #186 cyl heads and dual holley 660 center squirters

    [​IMG]
     
  4. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    like cardinal mentioned they're hard to tune and usually takes some time to get them dialed in but once they're set up correctly they make alot of hp . it took me about a couple weeks of tuning and trying different carbs and having sean murphy from SMI carbs tweak it a little but now it runs awesome !!!

    with a t/ram you'll need a hot ignition set up and run hotter than stock heat range plugs to burn all the fuel being pushed into the cylinders .the other is cold weather wreaks havoc on t/rams and i've had this issue but won't cause me to pull it because if that . basically since the carbs are high above any heat source during cold weather days you'll get carb icing and notice frost forming on the carbs baseplate ,this causes driveability issues .also with the 257/269 @ .050 cam , the dual holley 660's an tunnel ram i only get 9" hg of vacum

    at the 2009 route 66 rendezvous i used alot of gas just idling around the 2 mile cruise route and averaged about a 1/4 tank per ea lap i completed . i average about 5-7 mpg driving on the street with this set up but the trade off is a big smile when you hit the loud pedal and it keeps pulling hard up past 6800 rpm !!!:) :)
     
  5. tubbedz

    tubbedz Veteran Member

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    Weiand tunnel ram

    I ran a polished, Weiand tunnel ram about 10 years ago. The engine was a SBC 355ci with -461 "camel hump", 2.02 fuelie heads and a solid Isky Z-75 cam with about 575' lift and 1.6 rockers. That Isky solid was huge and I only had 5" inches of vacuum at idle with a 3500 stall, the power valves were 3.5's. The dual Holleys were both "4-corner" idle, 600cfm carbs and was a pain to get tuned. If you blew a power valve you would have to change all four, as why bother trying to figure out which one blew. But once the "initial squirt", power valves and jetting was squared away, the car "yanked" from off-idle to 7000rpm. My car had N50 Mickey's with too large 4.88 gears. It was a wild, crazy cammed car!!

    Currently, I run a Weiand 671 blower and this is a first for me. I thought the dual carbed tunnel ram was hard to tune, but tuning the big huffer is ridiculously painfull. Ouch!!

    .....just my 2 cents...build what u like and have fun with it...that's what I did
     
  6. Appstro

    Appstro Veteran Member

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    WOW!!! Thanks guys. This has been very educational! :) I think tunnel rams look so freakin cool. Looks like theres ALOT more than just a few changes that need to be made however. I am currently working my way from the rearend up and changing my one legger to a 3.73 posi. I'll keep going till I get to that tunnel ram!!!
     
  7. BondoSpecial

    BondoSpecial Veteran Member Lifetime Gold Member

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    What you really need, is a dual qjet'ed tunnel ram. That, would be unique.
     
  8. mrdragster1970

    mrdragster1970 Veteran Member Lifetime Gold Member

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    .

    1st, you're at the wrong track. There are ton's & ton's of tunnel rams at the track.
    Most fast cars have a tunnel ram, 5 & 6 second cars are 99% tunnel ram.
    Yes 8 jet's, and 24 air bleeds are a little harder to dial in.
    They are also worth 50-100 HP depending on what you start with.
    For slower cars they are probably not worth the expense, other than cool factor if that's what you like.
    As mentioned, a real tunnel ram needs compression, velocity and the proper converter ect.
    You can get a mild street set up, and there are ton's of old hot rods with them cruising the street every night.

    Good luck, and as mentioned, get what you like, it won't be that hard to learn.

    .
     
  9. hhott71

    hhott71 R.I.P 11/19/18 Lifetime Gold Member

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    I can't think of any of the top 25 cars in Super Pro, NO/E and none in Sportsman who run Tunnel Rams.
    Once in a while some goobeers with a jacked up El Camino (Think Earl Hickey) will have a Tunnel Ram. Now ya know why I put Goobeers, They weren't competitive or very fast. But they do drink beer well.
     
  10. ProStreet383

    ProStreet383 Veteran Member

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