Best manifold for ThermoQuad-equipped 340

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Captainkirk

Captainkirk

Old School Mopar Warrior
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All hype aside...which is the best street/strip manifold to use on a TQ equipped 340 for best numbers? I know the Air Gap has been getting rave reviews, among others but also heard good things about the Weiand Stealth. I could use an adapter but prefer a spread-bore manifold.
I do have the original '72 spreadbore Chrysler manifold, but it is one heavy SOB.
 
Weiand Action Plus.
 
Stock is good, you can mill the center divider down and gasket match it. I have done that you probably seen the pics of that intake before. I would also block the heat crossover and use one or two of the 1/4" plastic spacers under the carb. The 850 cfm quad is the one you want if it's going on a hot 340 and you plan on spinning it over 5,500.
 
The OE iron is a very good intake
There is a toss up between the LD-340 and the Weiand Stealth. I have not run the Stealth. I have run a LD-340 with a milled center divider and minor port work. VERY GOOD!

In the single plane world, the Holley Strip Dominator, then the MoPar M-1 which is a enhanced version from MoPar

Your looking for a street strip 12 second ride correct?

The OE intake is capable of doing so. You'll have an easier time with an aluminum unit though and the 2 dual planes should do it easy enough for you
 
The one cave eat to the aluminum intakes is the lack of abilty to accept the OE choke. You'll need to run and fab up a manual choke cable or adapt a electric choke. One such soulution is here, --> http://www.forabodiesonly.com/mopar/showthread.php?t=251220&page=2
Though this is a stock TQ choke adapted to a bi-metal choke carb. You can use a Edelbrock electric choke AFB choke BUT it works a little differently on the lever. It is possible to adapt it. I did but I have no pictures. Sorry about that. Use the old noodle and work it.
 
Reason the Air Gap gets all the raves..they work..as for that Thermo-bog.
 
Out of all the manifolds talked about so far, the Action Plus and the factory 340 are the only two that the Thermoquad can bolt directly to without modification. You see some LD340s every now and then that appear spread bore and people will try to argue they came spread bore, but they did not. The factory 340 (especially the 1971) is a very good piece and if I had one I would not look for an aluminum replacement. I would use it.
 
66fs said:
Love those guys. Got many a good carb from them, cheap. The only one I gave back was to a cousin when he saw how well it ran when I was done. Then he was bragging about it.
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You didn't get them from me unless you gone through the dumpster..where those carbs belong compared to a tuned Holley type..
 
I back what RustyRatRod says. The Action Plus is basically the same internally as a Stealth.

As for the Thermoquad carbs, I stayed away from them simply because I don't know how to work on them. But I am building a TQ equipped class car and luckily the previous owner knows all about them and is trying to teach me. He recently had some mid 1.3 60' times in his 318 TQ equipped SS Aspen running 10.60's @ 124! There are plenty of small block TQ equipped Stockers well into the 1.40's. Not sure if any hit 1.39.

Good carbs that can be a pain. Bottom line is that you just have to know how to work on them.
 
stroked340 said:
Cause' ya don't know how to tune em'...
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Much the same as some peple cannot tune and understand Thermoquads. Yall wanna bicker? Take that crap to PMs. That's not helping the OP at all. Pretty childish, stupid and selfish, really.
 
66fs said:
Wrong again. Got tired of "tuning" them. And they were slower and used more gas. Sorry RRR, you are right I just could not resist.
Click to expand...

I got sucked in too but I am trying to improve.
 
RustyRatRod said:
Out of all the manifolds talked about so far, the Action Plus and the factory 340 are the only two that the Thermoquad can bolt directly to without modification. You see some LD340s every now and then that appear spread bore and people will try to argue they came spread bore, but they did not. The factory 340 (especially the 1971) is a very good piece and if I had one I would not look for an aluminum replacement. I would use it.
Click to expand...



He hit the nail on the head here... :cheers:

Wiand Action Plus or the stock 71 intake are the best choice for a spread bore carb. :D

Adapters loose efficiency and power.... :wack:

Get what will bolt directly on the manifold...



I do have one LD340 that has been machined to take a spread bore. It was machined by someone before it got it. However it is not for sale as I like to keep a stash of parts and have some "options".... O:)
 
Really stroked340? Really?
Back to ruin another thread?
 
[QUOTE
Good carbs that can be a pain. Bottom line is that you just have to know how to work on them
[/QUOTE]
As with any carb really. Once you have a good core, nice and tight, it'll be all right.
There not as super tuneable as a upgraded Holley but but much better than a basic Holley IMO.
 
Use whatever brand of carb that you are comfortable with and can tune.

If you don't know how to deal with it or adjust it, you are just wasting time and money....
 
EL5DEMON340 said:
Stock is good, you can mill the center divider down and gasket match it. I have done that you probably seen the pics of that intake before. I would also block the heat crossover and use one or two of the 1/4" plastic spacers under the carb. The 850 cfm quad is the one you want if it's going on a hot 340 and you plan on spinning it over 5,500.
Click to expand...

Post pictures of yours. Show off. lol I thought it turned out real good.
 
I do every chance I get!!! That thing was a lot of work and HEAVY, I haven't even tried it and probably won't now that I have a 6 pack!
 

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