Can it be used on the 340?

in stock eliminator racing?

Yes, 70 Duster 340 AVS iron intake that weights a ton

The only intakes I see NHRA legal for Stock are the 1968-9 casting and the 1970 casting. It looks like the 1970 340 AVS only gets the 1970 intake, but the 1968/9 cars can run the 1970 intake as well.

275 340 DP 10.50 1-4 Cart AVS-4424S/SM 4425S/AUTO 2531915,3462848 1.5 H 63.3 C,2 Carb sizes – 1437x1686/1186xAV

Once NHRA opens the door for one, don't we all get in? Of course my iron intake flows well now.

I am not sure how Bill got that manifold approved for the 273. It was probably some obscure memo or something in the parts book. You would not want the LD4B on a 340 You would want the LD340 which was a copy of the cast iron 340 manifold. I remember when most of the 340 SS cars used that manifold.

SS cars can run any manifold they want, and the ld340 and others are not like the out of the box manifolds at all.

It's very possible he got the intake approved because originals are too hard to find. It may have a HP hit attached to it too.

Glad you said that, I had the two confused. I was just thinking of the weight savings on the front end.

i think this manifold was used on the "D: dart in 1964 and somehow it got approved for all of the 273 combos.

The D-Dart was 1966, two door hardtop. NHRA lists the convertible with the D-Dart engine too, but I've never seen any of those. My car is a two door sedan, so I can't run the D-Dart combo. It's a SS only car since they only made around 50 of them. It would be nice to get the Holley carb and bigger cam, but I think the D-Dart is still factored at the original 275 HP, 285 HP with the replacement head.

I'd use the 920 heads. That is what was on the D/Dart. They are a closed chamber and have a swirl port design. As far as the D4B goes, there were two of them. One has the Chrysler part number (CHRY2836139) cast into it. That might be the one you have to use.

I should swap cam, intake and carb and run my D/Dart in a stock class. Would that be legal even though it has an LO23 vin?

I'm pretty sure they don't check the VIN, otherwise there would only be two or so cars in the Hemi shootouts if they needed to be an original LO23 or BO29. I think you would have pretty much the same combo I am running, just that you have a hardtop and mine is a sedan. I don't think there was a large difference in shipping weights. I guess I was wrong, my 270 sedan is at 13.47, the 270 hardtop is 13.60, and the Dart GT hardtop is at 14.02. You can run two classes lower than my car. Natural M/S car.

I'm getting different opinions on the 920 and 302 heads. I guess I'll have to get some 302s for flow testing. I think the chambers are similar. I've been told the 302s have a bigger port. I have two of the LD4Bs with the Chrysler part number on them.

I have both heads here, a bone stock 302 and 920 and the 920 is by far the bigger port, smaller chamber even though both are closed chamber. The chambers are different, 302 has a heart shape and comes to a very sharp point in the middle of the chamber, the 920 has just one side filled in with no point, just straight accross, more like a magnum.

The 302 head was made for a roller cam engine that had a really bad pushrod angle, the bad pushrod angle needed a bigger PR hole, in order to accomadate the bigger hole they cast a whole bunch of extra metal right in the port PR pinch making it the smallest SB mopar port ever.

I haven't messed with any of those 318 heads in eons(like around 1993) but I do recall thinking the 920's were the biggest of the true 318 heads.

One thing about the 302 head is the valves are pretty well shrouded by the chamber walls. Also the ports are pretty small, but I don't have older heads to compare. But if you can't move metal in the combustion chamber the shrouding may be a factor.

R.

Ive been looking at maybe a set of these castings and the counter offer I got was very temping for new castings but these as well have a huge pushrod hole in the head and so id bet the port is very small.

http://www.ebay.com/itm/OEM-Dodge-Chrysler-Mopar-M880-318-NH-Cylinder-Head-4343723-4041001-/322134219161?hash=item4b00b21999:m:mXmYq0AIsu5czdvGaTt0epA&vxp=mtr

Nothing too special there, other than it's new.
Open chamber with the big pushrod holes. Must be the last version before the 302 head.

If you need some open chamber 318 heads for a rebuild or freshen up, it's a cheap enough price.

In ootb form the flow is so low on the 318 heads that the pushrod bulge really isn't an issue.