SBC tunnel ram

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555RAT
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SBC tunnel ram

Post by 555RAT » Sun Dec 09, 2018 11:35 am

After much research on tunnel rams it soon became obvious that much of the info is related to running a TR on the street. This topic is for a drag race only tunnel ram. My combo is a 414 sbc in a 1750lb dragster, 3.800 stroke by 4.165 bore, 13.9:1, afr 227 non eliminator done by epd a while back, 276/284@.050” on 108lca with a 104.5 icl, 1.6 t/d’s, 1.875” to 2” headers with 3.5” collector, 1.80 glide with 5800 converter and 4:30 gear. For comparison, with a Holley Dorton intake with mild porting and 1.45 X 1.75 carb I’ve run a best of 5.28@129 shifting at 7300 at my local track with a 1.19 60’. This track typically has around 4500’ da. The tunnel ram is an Edelbrock victor ram with 2 of the same 950 carbs I built to mirror each other with 1:1 links. I’m starting with 84 jets, .059 iab, .032mab(I’ll try and get .028), .029ifr, 2 emulsion at .028, .120 N/S, angled floats with the angle at the rear, BG 4 port regulator in front of the ram and planning on 5.5psi. My goal is to determine if the use of a tunnel ram can not only be faster but as, or more, consistent. Does anyone see anything that sticks out as “wrong”?
Keith

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Re: SBC tunnel ram

Post by Newold1 » Sun Dec 09, 2018 12:32 pm

Be interesting to know what a dyno will say. Know that adyno is not the answer to translating power to the track, but seems like your dragster is probably pretty well dialed in from a chassis standpoint and the only unknown here is how much more power , where, and torque is going to be increased with the use of a more complex intake and carb setup?
If plenum size is holding your engine down a little and it can eat and use the extra fuel then the dyno should show that. If it shows no plus or no change then just look at the old KISS theory in my opinion. There are also some tall, bigger plenum, straighter runner intakes out now and some great single big cfm carbs that work.
The Older I Get, The Dumber I Get :wink:

555RAT
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Re: SBC tunnel ram

Post by 555RAT » Sun Dec 09, 2018 12:50 pm

Thank you, unfortunately I won’t have before and after results and the only dyno near me is a chassis dyno but should be able to get me a baseline. The time slip will be my primary indicator of results as that is what will tell me what I’m after.
Keith

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Dave Koehler
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Re: SBC tunnel ram

Post by Dave Koehler » Sun Dec 09, 2018 3:27 pm

No more fretting, Stick with the TR.
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