Hey All, I'm looking into putting a tunnel ram on my stock 350 chev, with a th350 trans. I have been reading a lot on here about which carbs to use but everyone has a different opinion. The guy at the speed shop told me to use two holley 600's for all 350's and up. He said that they would be fine even on a basically stock 70's 350. And he said that you would only use 450's or 390's on something smaller (283, 327). Is this guy right should i go with the 600's? And also progressive linkage? I am planning on buying this in a together kit so i get a better package deal. I am also thinking of using a pertronix ignition(just wondering what's your thoughts are on this?) Jay.S
Hope he means 600 center squirters. Tunnel rams are for high RPM's and with an auto and no low gear ratio it will be a dog no matter how lite your car/truck is. And yes if set up properly with the rite combo stall converter and rear ratio, etc. you could use the 390 - 500 Carbs.
I would not put that on a stock 350. Tunnel rams are for higher RPM's and do not perform well for daily drivers. I don't think you will be happy with it unless all you are concerned with is looks.
The fact that you are asking indicates that you don't understand the premise of a tunnel ram and the parts that it will be compatible with. If you are looking for visual impact, get it somewhere else besides your induction system. You'll be much happier.
_______________________________________________________________- On your stock 350 a tunnelram will not fly. It doesn't matter what size the carbs are. If you are talking a stock old LT-1 with a solid cam, 11:1 compression and 2.02 heads than maybe a tunnelram with 390's might fly with a stick and some rear gears. If you have a run of the mill 350, 9.5 or 10:1 compression, small heads, stock cam and the automatic..... s**** the tunnelram idea............
Tunnelram is fine BUT you have to have others parts to make it work properly. Fairly stout cam, high stall converter, low gears, headers and the Pertronix would work fine but you still loose your bottom end torque. mine works great over 2600 rpm but my 55 is set up so that my tunnelram works with the rest of the drive train. I run 2 Edelbrock 500 carbs on the sbc and they work great but you have got to take your time setting them up . Every little adjustment you make you have to make on both carbs once you get them close and even the smallest of adjustment makes a differance . Hell I've had mine on for 2 years and love it on the street but as said before, you gotta set the rest of it up to work together. Good luck
Do a search on here and you will find a ton of info is already present. The topic has been discussed many, many times... ...and I would agree that if you are asking, you are probably about to get in over your head. However, all of that being said, back in the early 1980's I had a tunnel ram on an essentially stock 283 with a pair of 600 vac secondary Holley carbs (no progressive linkage). It was an EVERYDAY driver with a 4 speed and 3.73 gears. I drove it every day through Indiana winters rain or shine. I put a garbage bag over the breathers if it was raining during school or work. It ran pretty good and was a lot of fun. But it was actually faster with a 2 barrel intake... I have dual 4 barrel 500 cfm Edelbrocks (Carter AFB style carbs) on a cross ram today. The engine is built correctly for RPM with a BIG cam, big heads, steel crank, forged pistons, appropriate ignition, manual trans, 4.88 gears, etc, etc. It is the proverbial "Don't over cam, over gear or over carb your motor" story that you used to read in every magazine and hear from every expert. It is a fact that it is way more fun horsepower wise, but way less fun on the street for everyday driving. A lot to think about...
I ran a tunnelram on my 327 with a pair of 500cfm edelbrocks. Think i had about a .480 lift cam, doublehumps, mild convertor, decent ignition and ran this combo many years without worries. Great setup, had it on my old '36 pickup and you really wanted to point it nice and straight when you stomped it. I wouldn't use those 600 vacuum secondaries, poorest excuse for a carb holley ever made; 600 center squirts would be interesting if you can find some in good shape. They were creative carbs for sure. Think they were made for the tunnelram. Anyway, go for it. Later, oj
Hi Jay I have run tunnel rams on stock 350's and other combinations on the street and was quite happy with the combination. I used 2 600 vac. secondary on a Small plenum Weiand manifold. These carbs are fairly straight forward. Spend some time on jetting and secondary timing. Cold air/carbs,runner length and direction are beneficial for mileage/torque and horsepower. Mileage was great on the highway and can't comment on city as I never cared. I like the looks and would do it again in a heart beat.
Go to the search feature here on the HAMB. Then go to the "Advanced" area and type in Tunnel Ram. Then click on "Search ***les Only". There are almost 70 threads relating to the subject and plenty of good reading material to absorb. Good luck with your project. The pics look like a killer start.
The combo with 450s they sell on summitracing is the small tunnel ram that actually builds torque some what like a tuned port tpi intake of the 80s. But, this isnt efi either so they still run like **** if your carbs arent tuned. Edelbrock also has a street TR version too. So, at least start with one of those. You still need a mid range cam 235 duration on a 110 at the very least, stick or 10" 2500 stall or more and 3:55 gears to start off. Progressive linkage is what you need that way your not running around opening both carbs all the time. Again edelbrock has this figured out and I like the combo of carbs and linkage they have. Long time ago, I had a weind single top with 3310 Holley and switched to 750 Edelbrock on a 350. Also ran a weind single top with 850 on a 408 bb
from what i've read Ram inductions only are made to work at 1 rpm,(around 6k) they have a little bump in the HP curve at half that (3000ish) but unless you are turning 6k regularly they are a bad idea
The 600 Holleys are waaaay toooo much for your stock engine.I'm using 450's on mine,and my engine is radical.Re jet the carbs to the smallest you can get and set the regulator at about 3 1/2 pounds of pressure.This should get you a driveable combo.
Thanks guys for all the info, i realize a have alot more research to do before i make my final decision.
I run Tunnel Rams, but there's alot of issues....power valve changes in the Holley carb of choice, jetting, camshaft choice, converter, gear......Definite a High RPM intake....you gotta love'm, or they will drive you crazy
I have had a tunnel ram on my big block model a pickup for 10 years now , have made 7 trips to bonneville (750 miles one way) with out of the box 450 holleys,
Yep Holley 4224's They can really help throttle response even on a cross ram. Thing is new they are $700 now.
390'3 or 450's on any smallblock from stock on up thru fairly warm engines. 600's only for really stout setups with a pretty warm cam and stout gears. I've run dual 500 cfm Holley racing 2 bbl's on the street with no problem........
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