I have a '71 340 that is going into my '73 Duster. It has "home ported" 2.02 J heads on it, the standard .480 lift hydraulic Purple Stripe, and Hooker Super Comps. I'll be using a Coan 3200 stall in a 904 with either 3.91 or 4.30 gears. Car will weigh around 3400ish with my fat azz in it.

Right now it has a TM-5 on it and a 3310 750 cfm Holley. I plan this to be just a toy that will get driven around now and then and raced occasionally. Is there a better intake for what I am doing or is the TM-5 a good piece?

Thanks!

Performer RPM.

Port‑O‑Sonic

I believe the TM-5 is a Tarantula. In my opinion, that and the original Torker are obsolete. They will work, but aren't the best for that application.

I'd strongly recommend a good dual plane intake, like the previously mentioned RPM/Air-Gap, or regular RPM if driven in cold weather. LD-340, Weiand Stealth or even the smaller port LD4B would be good options. A good dual plane will provide more HP and torque in the range that the combo will spend most of it's time in. A dual plane will be more responsive and easier to tune, especially with the accelerator pump circuit not having to compensate for a too big plenum area..

I did a lot of track testing between a Weiand Stealth and Holley Strip Dominator on my race car. The Holley came out on top by about maybe a tenth, BUT, I have a lot more gear, cam, converter, etc. When I launch and the converter flashes to 5,000+, it might dip a hair below that (on a bad-air day) on recovery but stays above that the rest of the run.

You can always experiment with straight or tapered 4-hole spacers and carb tuning.

Here is a dyno comparison of several intakes. But I believe the Torker II was modified and the others weren't. It appears that the carb was rejetted to optimize it for each intake. It does matter. In my test the Stealth liked the deeper plenum side to be jetted a couple of numbers higher than the shallow side (or the shallow side leaner, depending on original jetting)! Don't know if that will work on other dual planes, but you may get a hint from a good plug reading and seeing if there is a color pattern related to which side feeds which cylinder.

The "area under the curve" is important, which roughly is the rpm range that you'll spend the most time in. "Peak" numbers don't always make the best performers.

http://www.hotrod.com/how-to/engine/mopp-0108-dyno-testing-small-block-intakes/

I love my performer rpm.

For a street and mild strip combo like yours, I think a 650 dp would perform better than a 750 vac sec carb.

Plenty of guys in the mid-low 11s with an RPM Air Gap on a small block. The 3310 will bolt right up to it no problem but you might need a high-rise throttle cable bracket and/or a longer cable.

Since the car is on the heavier side and as you probably know, a 340 won't make tons of torque in the lower RPMS, you will likely need the 4.30 gear if you stay with a single plane. My old 340 combo with a Victor intake absolutely needed the 4.30 gear, even over a 4.10.

Conversely, you would probably be able to get away with the 3.91 if you go with a dual plane.

I'd run a Performer RPM or RPM air Gap and a 4777 650 DP on that combo.

The TM5 is a very good manifold, good top end power but suffers from the smallish early 70's technology plenum for torque. If you ran a 4 speed I would probably just keep it on there...you could do a lot worse. There are better Single planes out there but on your mild combo it might not be worth the swap in terms of 'real-world' et/MPH. What hurt the Tm5 was it was not much better than the Torker and not as strong as the Victor

The RPM is just a great all around manifold for a 340 where the bottom end-through upper middle is going to propel the car mores than the top of the power curve...really your best choice, or certainly your most fool proof that it will be an improvement over what you have.

If I were doing it and the intended use I
would go with the AIR GAP.. it works great in
the RPM range you will ever be playing in..
plus you wont need the steep gear...the only
other thing I would change besides the intake
and gear would be to add a low first gear in
the trans... would be fine for the street and
the few times you would go to the track

LD340 and 3310 750. DP on the street drink too much fuel, and the correct secondary spring will yield good transient response out of the vac sec carb

Maybe call darthv8r for a cast iron upgrade?

Especially w/a proper calibration...........

You read my mind.

You are a sick and demented man!!!

A Strip Dominator and a thumperized 750 double pumper. Anything else is just screwing around.

Or, you have a fetish of some sort...but I won't mention any names of members whose one desire is to make cast iron dust.

^^^^^^^...this for street, although on the strip my 340 '71 Cuda ran 2/10ths quicker with an 850DP.

Nothing wrong with the TM-5.

RPM Air Gap with a 2" spacer

Thanks for all the info everyone! Think I will keep my eyes open for a deal on an RPM Air Gap. For the time being I will stick with the 3310, but if it's a pig I will save up more pennies.