I have had a Weiand Tunnel Ram pat# 3581408/5988 for over 15 yrs now, & I found a old Mister Gasket Scoop at a swap meet. So now I am tired of looking at it on the shelf, & want to use it on my Model-A Pick-up. My set up is a 302 with a C-4 I am just wanting the looks not the HP. So how much work is it to get it to just be a good driver with the COOL LOOKS. What carb's should I use I drive it a lot, having a little stall at take off is fine with me as long as I can drive it on the hwy & cruise with it. Thanks Bill
If you are talking looks, you need two carbs. I had a couple of small holleys on a 350 Chevy and it worked fine. Neal
i run two 450's on mine. had a awful bog til i put the right power valves in now it runs and drives fine on the street but man it loves gas stations... lol
Had a single 4 on a 84 ford ranger with a built c-4. Truck had a one legger and we could roast the right rear tire from new to maypop in about 1/3 of a mile. Good times had in my youth.
I agree, although you can get by with a single carb, on a tunnel ram two smaller carbs are better than one bigger one. Even then, distribution isn't always ideal. On race engines it's not unheard of to jet each carb throat differently to help even things out. The smallest Holly four barrel is 390 CFM. On an open plenum manifold like a tunnel ram two of those is a lot of carb for a conservative street engine the size of yours. You might consider a pair of 500CFM two barrel carbs. That 1000 CFM converts to about 650 CFM in the four barrel rating scale. The large manifold plenum will still promote the tendency to bog at low RPMs, especial when the engine is cold. But, with appropriate accelerator pump calibration it will be a lot easier to live with than if it has too much carb.
I've got 2 450 holleys that I pulled off my 350 t-ram that I'd make ya a deal on. Went to 750 Edelbrocks.
I've run a single carb top on tunnel ram before and it actually ran OK. The problem is it's such a dog off the line because the carb is so far from the engine that it needs a whole lot of accel pump shot to get it going. That's why manual trans cars work better than auto cars. But it will run just fine with a single carb, it just looks a little off. I do know that when I finally switched back to a regular single plane intake with the same carb, I swear it felt like I gained 50 hp!
Thanks for the info guys I am almost ready to put it on the truck. I found a pair of 450 holleys off of e-bay for $265 they seem to both be in fair shape & came off of a running car. I will post when I have it up & running with some pic's, it just takes time when you are on a fixed income being retired.
Don't just toss carbs on and expect it to even run OK, let alone great! I've got tunnel rams on both my street g***ers, and I've helped several others set theirs up also. Single carbs don't work well because of poor fuel distribution, and dual carbs need a lot of work, if you get the wrong carbs. I put twin 450's on my first tunnel ram, and they were Holleys with mechanical secondaries, but no secondary accelerator pumps. Don't make that same mistake, as it took a lot of fooling around with accelerator pumps, nozzles, jets, timing, etc. to get it to run well. Those that I've done using twin carbs that have vacuum secondaries, and are sized large enough, work great out of the box, and with some tweaking will run even better! Doesn't matter if you like Holley or Edelbrock; save yourself some grief and go dual carb, vacuum secondary. I'd also say the opposite of what some said about going small. Too small and you'll have issues with starving off idle. Your 302 should handle 450 or 500 cfm carbs with vacuum secondaries, as the secondaries wont open until the engine calls for it anyway. If you consider they are 450 cfm, then on the primaries you're only feeding the engine with 450 cfm with two carbs. I'm using two 450's on my 327, and two 600's on my 464. The 464 is vacuum secondary, and I've never tweaked a screw on them. They ran fantastic right out of the box.
The single four tunnel ram is hard to beat for power and simplicity, plus mpg. I had one on a 383 mopar, and my brother liked the way it ran so much he put one on a 66 mustang with 302. It wailed!
Has to be doubles or it looks bad to me. Here's the setup on one of my ot projects. Also, please don't use the fake "Enderle" style scoop, those just look too fake and the proportions are all wrong. JMO, SPark
MPG? Two fours are not less economical than a single four, unless the operator can't control his right foot. My Austin's 327 +.040" with twin 450 Holleys on a TR gets 21 mpg on the highway with a TH350, and 3.73 posi. behind it. The number of carbs doesn't equal MPG, it's how you drive, and how they are setup.
(2) 500 2 bbls is a lot of carb = 1000 cfm (2) 390 4 bbls = only 390 cfm while running on the primaries... It will take some tuning to get the bogging and hesitations worked out. Make sure your ignition system and advance systems are working correctly.
Here in sunny California, my buddy runs 2 - 450 on his tunnel ram. On really cold mornings, it doesn't want to start. He runs a sbc in a T-bucket with a jag rear end. His gears are in the 3:70 range and he has a 220 stall converter. If he punches it from a dead stop, it will bog then take off. He's had it for 18 years now and puts on 8K a year.
Having just broke in the cam on the single quad tunnel ram I can attest to it being somewhat cold blooded. Once it warmed up though it had AMAZING throttle response. Haven't driven it yet but I can't wait!! Single Carter 625 AFB on a Weiand Tunnel Ram.
I have a manual choke on my 464 with twin 600 Holleys, and it starts fine with choke off, but it needs a little choke when cold to keep running. I think if I removed the choke plates and simply used the fast idle on the chokes it would work fine. The twin 450's on my 327 start, run, and idle just fine cold, and don't even have a choke if I needed one.
Only one way to go.. 660 center squirters. Ran them on an old 302 and my 455 olds. It's all about How you tune the carbs.
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