440 Tunnel Ram Help

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440dartsport

440dartsport

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I am running a .030" over 440 with 10-1 comp. The cam is a Hughes solid .610/.614 lift with 1.6 Hughes roller rockers. Indy EZ-1 heads and Indy tunnel ram. My question is what carbs would you recomend? I was thinking 2 650 Holley double pumpers but maybe something bigger??? The car is a 74 Dart Sport with a 4 speed and dana 60 with 4.10's. It is going to be mostly a weekend street car with a few passes down the strip. If someone could post up some pics of there tunnel ram linkage and fuel lines set up, that would be great. Thanks in advance.
 
I'd say the 650dps would be a good choice, maybe even some 660 center squirters.
 
1wild&crazyguy said:
660's were considered the ticket.

the 600/650/660 will all work great.jmo
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Yeahh...............ah. and a real pain in the *** on the street. CS carbs were NEVER intended for anything more than WFO (W ide F...... O pen)

The "transition" if you can call it that between ?? idle ?? and the "I wish it had" low/ med cruise and onward to power at WOT is pretty much just not there.

Part of this is caused by the very design--you are opening secondaries at the same time as the primaries, and secondaries were never intended for anything other than lots of power. Add to this that the gear drive is nor realy all that precision for "just off idle" then add to that you have TWO of the damn things, and you've got a real mess on your hands at off-idle and low cruise.

'Course, you could just ignore the police and do a "mini launch" everytime you leave a stop

For street use, stay with small DP or even (cough gag) a pair of small vac. secondary carbs
 
My friend ran around with a tunnel ram 2x450's dp's on a warmed up 340, it had plenty and worked good in all ranges.

cs?

secondaries are staged in a dp, I'm missing where yer going with this, the transition is coaxed with the shooters ''dp''

I know 600 dp's will work fine.
 
1wild&crazyguy said:
My friend ran around with a tunnel ram 2x450's dp's on a warmed up 340, it had plenty and worked good in all ranges.

cs?

secondaries are staged in a dp, I'm missing where yer going with this, the transition is coaxed with the shooters ''dp''

I know 600 dp's will work fine.
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You are talking about dp, -a perfectly streetable carb. I'm ragging on the pretty much race only center squirt, which had a gear drive tying all four barrells together, and one "center squirt" pump supplying all four
 
Correct the center squirt had had one pump. It filled all barrels regardless
 

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The center squirtors were designed for blower and tunnel ram combinations. That's why the linkage on promary and secondary is 1:1. Meaning it opens all four barrels the same amount for a given throttle position. That would be why there is only one accelerator pump squirtor on them. They are the best carbs for the right combination using a tunnel ram. However the whole package has to be matched. I think in this case the static ratio is low, the cam is large, and the tunnel ram is going to feel soft down low with the CS carbs. I'd go with nothing larger than twin 450s on it for that reason. It's not going to be revving like mad and I'd want to give some decent throttle response givent eh stick and street use.
 
for the street 2 600/650/750 vacuums may be your best choice. of course that depends on how much you can spend on linkage. the 600/650's can mount inline with side hung float bowels, simple inline hook up and the 750 with center hung bowels will have to go sidesways which ups the dollars for the linkage a bunch. my bracket hotrod had pretty much the same motor set up as yours and i used 2 600 vacuums and it would et to 10.90.
 
depending on how racey you drive it on the street, i have 660s on my 418 street car, they take some getting use to, yes they like wide open. id say if you really like getting it on the street id look for 2-650 double pumpers, then buy 2 holley or pro form main bodys ,they are like 125.00 a pop, they have the air horns milled, and have screw in air bleeds, you can probably start lookin now and get a 650 for 100.00 bucks or so on craigslist/ebay/jaxed , then you will have a nice pair of carbs, someday i would like to get 2-e 85 750s, my carbs are side ways, im going to redo my fuel lines this winter, and make a air -pan and seal it to the hood, later brian .
 
If you want a street-able set up I too like Bob stated run 2 600 1850 style vac secondary carbs. I have street drove 340's to 426's over the years and the 600 vac secondary carbs are much more user friendly.
 
Look at my avatar Im going to use 2 1850 VS carbs. I believe these will be more street friendly and can be had cheap. I bought these off ebay rebuilt and they came to me BEAUTIFUL I believe they were $150 per carb or something like that.
 
no problem running double pumpers on a tunnelram, thing is that a tunnelram will see a set of fourbarrelskind of like a I.R induction system but with a plenum to take most of the pulses out since 99% of all fourbarrels cant handle pulses very well most 4barrels are made for a constant flow,well as constant as it can be.. i spoke to a very inteligent and experiences coworker about all this stuff when i put the tunnelram on my 340 and he said a tunnelram will work absolutely best all around with a set of carbs that will open the secondarys at the same time as you open the primarys 1:1linkage is goood for it, i had way to much carb on my little tunnelramed 340 but he was right and i tried it with a corrected 1:1linkage and it did work better than the standard linkage on my proforms..
if it was my 440 in this thread i would go for the 660s they may be alitle small but they are made for it, if you are realy bent on having vacum carbs i would use a set of edelbrocks,they work pretty good on tunnelrams out the box, if you go ahead with normal doublepumpers i would sugest that you atleast try it if you can find a nonprogressive linkage for them it wont be a catastrofy with the stock linkage but you may be pleasantly surprised, i was!
 
Thanks for all the replies guys. I am going to start out with a set of 650 double pumpers. I already have one so I just need to pick one more up...
 
I know that this is an old thread, but I'd like to give my advice/opinion on subject for anyone who looks at this for advice. Do not use 660 center squirters on any kind of street car. There is no power valve circuit. If you're familiar with how a drag race car with blocked powervalves drives, well, that's how 660's are.
 
They were intended for stick shift drag cars that launched at high rpm. They could possibly work on
a modern drag car using a 2 step, trans brake, and very high stall converter, but in my opinion they
suck. I let my buddy trade his pair of 1850's that I set up for his 427 Chevy for a pair of 660's. Big
mistake! I also used 1850's on 2 440's. On an Indy Head 517 Dodge, I used 950 HP's.
 
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