Tunnel Rams

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

  1. Rich Schmidt

    Rich Schmidt Veteran Member

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    Actually a well set up tunnel ram doesnt kill low end torque that much. It actually should add a good bit of mid range torque. The down side to the tunnel ram is that there is so much metal to get heated up before the engine will idle properly and not want to run lean. With any tunnel ram,the secret is to run the minimum plenum volume possible that doenst hurt power. I have toyed around with the idea of replacing the single 1150 on my engine with a pair of 660's. I have some ideas on how I would like to build a cutom bolt on top for the plenum that would allow me to reduce the plenum volume alot and then add some super sucker type carbs spacers to imporove the signal to the carbs. In any car with over a 3500 stall covertor you could almost certainly pick up soome power everywhere with a tunnel ram. The real secret to how it works is that if it is designed right it will alow you to put substantially more carb on the engine will still getting a good signal to the carb and get good mid range response while still getting the benefit of the extra carb area at the top end.
     
  2. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    the tunnel ram i was running a edelbrock TR1-X had very good street manners yet it was able to make alot of hp and tq higher up in the powerband .these older edelbrock t/rams were called bread baskets refering to the large shaped plenum . the TR1-X were a 2 piece design that had a plenum that was 6" tall 6" wide and this plenum shared both carb baseplates .the lower section or the intake runners were about 8" tall and were not a very large runner about the size of a victor jr so the intake velocity was really strong which helped keep the carb signal strong

    these older design TR1-X tunnel rams are readily available thru ebay or on racing junk for about $150 and since they've got a 2 piece design and you're lucky to find it there's a single carb top you can put on it
     
  3. pinoaktwh

    pinoaktwh Member

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    Just curious,,, What is it about the 450's and the 600's that some of you do not like?
     
  4. rtanner

    rtanner Veteran Member

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    on the 450s i never could get enough accelerator pump shot, for my driving style, 600s tuned out ok no problems they were inline, my new setup has 750 mech secondarys mounted sideways it works very very good!!!
     
  5. pinoaktwh

    pinoaktwh Member

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    Were you having a hesitation issue?
    I agree the carb depends on your engine setup.
     
  6. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    a 450 holley even though holley lists it for multi carb set ups and which is a mechanical secondary carb but it doesn't have a accel pump squirter for the secondary side . when you crack open the secondaries you get a momentary bog/flat spot because it goes big time lean from lack of fuel .that's why i switched to a holley 660 center squirter as these are built specifically for multi carb set ups and work perfectly right out of the box
     
  7. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    also a mech secondary carb is going to work so much better on a tunnel ram set up than a vac secondary carb will ever do .you gotta remember that a t/ram is going to have a lower vacuum signal because of the huge plenum and long runners . and if you run a vac secondary carb it's really hard to get a good vacuum signal to the secondary vacuum pot . you also have to run a vauum line inbetween both vacuum cans so that both the carbs secondaries open at the same time
     
  8. pinoaktwh

    pinoaktwh Member

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    I do not have a bog/flat spot with my car, but I have witnesses it with others. True, I had to tweak my accel pumps when I was dialing it in, but I have had no issues with them in over 4yrs and the transition from the primaries to the opening of the secondaries seems to be instant.

    I actually asked the question to find out if someone really knew the "flaw" with the 450's.. Alot of people make the statement and do not even know what the reason behind the reputation comes from.
     
  9. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    the main issue with the 450's i've heard alot of people complaining about was the lack of a accel pump on the secondary side and the large flat spot/bog it made when opening up the secondaries
     
  10. pinoaktwh

    pinoaktwh Member

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    Ill try to post a video of mine in the next couple of days. But yes that is the issue with them.
     

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