looking to find specs on 340-X heads.

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They have 2.02 int valves and 1.60 exh valves. They were used only on a 340 from 68-71. Chambers usually cc out at approx. 72 cc's in stock form. I have a set and flowed them in basically stock form. The only diff from stock was they had a good multi angle valve job and stainless REV valves. Here's the numbers


Lift----Int.----Exh
.100----60-----50
.200---120----104
.300---173----131
.400---210----143
.500---220----146
.600---215----148

They were milled .010 and with the stainless valves cc'd 66 cc's.
I think the REV valve design took up a little more space so that's why they cc'd so low.
 
Fishy, I believe the 'X' heads (894 castings) were only used on the '68 and '69 340's. The 'J' (915 castings) were used on the '70 thru '73 340's and the 360's of the same years 1970-1973. c
Please heck this though, I could be wrong.
Terry
 
Head casting#2531894 "x" heads..were used on 340's "only" from '68-'71..cc's were 63.0-73.5...
 
up to 70, and there no better than a set of j u o head as all the runners are the same on all heads. If I were doing a restoration I would buy a set of j o or u with the 1.88 intake and have it machined for the 2.02 valves ,this is like buying a new head as there has only been 1 valve job done to them, I would buy a j head over the infamous ,lol, x head as their crap to begin with as your flow #s dictate, buy a set of eddies or victor if you want to go faster than 12s in the 1/4 mile. no offense meant but the x heads are way overrated and way misunderstood .
 
well they cam with the 360 I bought for 350.00. I think I got a good considering they look like they had never been re-done.
 
thanks I will have to check the casting # again when I get them back from the machine shop. the machine shop told me that the heads are cracked though. I am kinda bummed about it and wondering if the shop is just pulling my chain.
 
mopar1962 said:
up to 70, and there no better than a set of j u o head as all the runners are the same on all heads. If I were doing a restoration I would buy a set of j o or u with the 1.88 intake and have it machined for the 2.02 valves ,this is like buying a new head as there has only been 1 valve job done to them, I would buy a j head over the infamous ,lol, x head as their crap to begin with as your flow #s dictate, buy a set of eddies or victor if you want to go faster than 12s in the 1/4 mile. no offense meant but the x heads are way overrated and way misunderstood .
Click to expand...

Sorry i disagree..#1 the x-heads were available til '71..#2 they came with 2.02's...o's,j's,u's never did 1.88's only so if you put 2.02's in those heads you've also got to get them to flow better to take advantage of the bigger valves,ie:work to the runners ect..you just don't slap a set of valves in.. but i do agree Edelbrocks are the head of choice now...But until the Edelbrocks came out x-heads were the choice of many!!
 
1972dartman said:
well they cam with the 360 I bought for 350.00. I think I got a good considering they look like they had never been re-done.
Click to expand...

If it was me I'd at least make them show me the cracks so you know your not getting ripped off. The X heads are valuable peices today for guys looking for original parts for restoration and their are crooks out there that might say their cracked just to make a buck.
 
I would buy a j head over the infamous ,lol, x head as their crap to begin with as your flow #s dictate, buy a set of eddies or victor if you want to go faster than 12s in the 1/4 mile. no offense meant but the x heads are way overrated and way misunderstood .
Click to expand...

OK, soooo, Edelbrock makes Victor heads for a S/B engine? Fishy's head flow numbers are preety nice for a OE head given very little in the way of a performance treatment. For the price, there a good bang for the buck.


340srule said
..#2 they came with 2.02's...o's,j's,u's never did 1.88's only
Click to expand...
I have had alot of people stand up and shout different. I myself have not seen a 2.02 in those heads. But if the heads come cheap, adding a nice set of valves and even a pocket porting job, the price is good and performance is nice, a compareable bank for the buck agianst Edelbrock heads.

Dartmans $350 for the heads are not a bad price to start with.
 
It should also be noted that early X(894 castings) may not have an X by the spark plug hole. Mine don't, pics can be provided.

Matching number 68, 340, Formula S, with an early 8/68 build date.
 
340srule, I agree..the 340's do rule. But I must respectfully disagree on the '70 model 340 heads. They were the 'J' 915 castings and yes they came with 2.020 valves. I have had several sets of them myself. The 894 'X' castings were used on the '68 and '69 340's only. Might have been a few very early '70 models with them but the official casting for 1970 tru 1973 was the 'J' 915 castings. No question about this at all. Do you remember the six-pac heads with the pushrod hole machined for offset rockers ? Well those were 'J' 915 castings and the year was 1970. Also the first year for the 360 was 1971. They had 'J' 915 castings. And the year was 1971. The 915 castings had 2.020 intake valves in 1970 and 1971. 1972 and 1973 340's and all 360's 1971 -1973 with 'J' heads had 1.880 intake valves. As did all 360's. But..as was stated above, all the LA heads were almost identical in performance and flow, with same valve sizes of course. One years castings weren't really any better than another. Actually there's probably more difference in two different flow benches than in the different castings themselves. And they all respond the same way to the same port mods. So unless you have to have a 'correct' years casting..use what you have they are all good. Terry.
 
I won't argue the point of what yrs. used what heads because I haven't had enough different ones to know. But according to my "Small Block A Engines" manual from Mopar the 894 X head was used from 68-71 on 340's. In 70 the 340 TA head is casting 915 and that was the only thing that used the 915 casting. In 71 only the 360 got the 915 head (small valve). It says it wasn't until 72 that the 340 got the 915 head.

Here's the page from the Mopar Perf. book. Sorry it's kinda blurry. Scanning from a book is hard to get a clear pix.
 
This is splitting hairs. MP books have good info, but you can not take it as a BIBLE and final word.
 
Fishy, your book is wrong. LOL, LOL. The fact ramains that in 1970 the 915 castings were introduced on all 1970 340's. I know I was around then. I pulled the heads off a buddies 1970 340 Dart swinger in the early '70's and they were 915 'J' casting heads. That was so long ago, I was still in the Air Force then but I remember it well. He had a bent crank. He never put it back together and he ended up giving me those heads. Don't want to extend this into a pissing contest but I know what I know. Try a different source and check that out. But as I said before, LOL,LOL...it doesn't matter which LA casting you have, use it . It is as good as any of them. We will just have to agree to disagree..and that is ok. Good luck,
Terry.
 
I meant nothing contrary against anybody. It's very possible that my book is wrong. And Rumble is right about it's like splitting hairs because as most of us agree they're all basically the same heads except for the valve size.

Terry I'm sorry if I offended you.:hello2: I didn't mean too. Was just stating, respectfully I might add, what the Mopar book showed. That's why I posted a pix of it.

I did also read the same thing online somewhere in the past but I don't remember where that was now. Possibly it was based on the same book I have???

I wish we did have a dependable mopar Bible to go by.:book: Would save allot of confusion.
 
headsbikesmopars said:
340srule, I agree..the 340's do rule. But I must respectfully disagree on the '70 model 340 heads. They were the 'J' 915 castings and yes they came with 2.020 valves. I have had several sets of them myself. The 894 'X' castings were used on the '68 and '69 340's only. Might have been a few very early '70 models with them but the official casting for 1970 tru 1973 was the 'J' 915 castings. No question about this at all. Do you remember the six-pac heads with the pushrod hole machined for offset rockers ? Well those were 'J' 915 castings and the year was 1970. Also the first year for the 360 was 1971. They had 'J' 915 castings. And the year was 1971. The 915 castings had 2.020 intake valves in 1970 and 1971. 1972 and 1973 340's and all 360's 1971 -1973 with 'J' heads had 1.880 intake valves. As did all 360's. But..as was stated above, all the LA heads were almost identical in performance and flow, with same valve sizes of course. One years castings weren't really any better than another. Actually there's probably more difference in two different flow benches than in the different castings themselves. And they all respond the same way to the same port mods. So unless you have to have a 'correct' years casting..use what you have they are all good. Terry.
Click to expand...

The above is all correct. While the casting numbers were different they are basically all the same head except some had the smaller intake valve.
 
Fishy68,
You didn't offend me. Not at all, LOL. And I didn't take it like you were disputing my comments. And I surely hope I didn't offend you. I enjoy a good tech session with my Mopar family. I surely don't know it all. And I hope it doesn't come out like that. The sheet you posted is also on Moparts in the archive section. I am sure that is were you saw that. I wouldn't hesitate to use any of the different LA castings if I had them. That is really what I was trying to say. This was a good topic. I enjoyed it, thanks guys. Now,..next topic. Why did Mother mopar use those 'tulip' shaped intake valves anyway ? LOL.
Terry.
 
D-mailman said:
Fishy68,
You didn't offend me. Not at all, LOL. And I didn't take it like you were disputing my comments. And I surely hope I didn't offend you. I enjoy a good tech session with my Mopar family. I surely don't know it all. And I hope it doesn't come out like that. The sheet you posted is also on Moparts in the archive section. I am sure that is were you saw that. I wouldn't hesitate to use any of the different LA castings if I had them. That is really what I was trying to say. This was a good topic. I enjoyed it, thanks guys. Now,..next topic. Why did Mother mopar use those 'tulip' shaped intake valves anyway ? LOL.
Terry.
Click to expand...
I'm no expert but I do know 68 & 69 had dome style piston . 70's I believe went to flat top pistons X heads were more open chambered for this ?
 
New leader in the "Bring out your dead" competition... :)

The thread is almost 10 years old and no oem 340 piston in a vehicle had a dome... all flat tops and some stick out the deck.
 
Be gentle now, be gentle. He is obviously new, not to just the forum.
 
To stir it back up.
For a fact.

I have a pretty original, but rusty 70 cuda, it has a 340 with X heads. Engine is still in the car.

And I pulled a set of J heads off a 1971 360 county police cruiser when I was a young, around 1982 that had 2.02 heads.
 
sireland67 said:
To stir it back up.
For a fact.

I have a pretty original, but rusty 70 cuda, it has a 340 with X heads. Engine is still in the car.

And I pulled a set of J heads off a 1971 360 county police cruiser when I was a young, around 1982 that had 2.02 heads.
Click to expand...
OK, I deserved that. I did mean stick out of the deck.But I thought only 68 and 69 . I have a 68 340 out of GTS I bought a set 20 over of KB 243KTM-020 Hyperkenetic Pistons and a set of Eddy 60179 heads stock deck height and .050 Eddy Gasket set . Would like Comp. ratio opinion . I was reading this post because I didn't know what X head CC volume was .
Piston specs

Part Type:Piston and Ring Kits

Product Line:Keith Black KB Performance Piston and Ring Kits

Summit Racing Part Number:UEM-KB243KTM-020


UPC:800745166180

Bore (in):4.060 in.

Bore (mm):103.124mm

Piston Style:Flat top, with two valve reliefs

Piston Material:Hypereutectic aluminum

Compression Distance (in):1.840 in.

Piston Head Volume (cc):+6.00cc

Wrist Pin Style:press-fit or floating

Pin Diameter (in):0.984 in.

Gapless:No

File Fit:No

Top Ring Thickness:5/64 in.

Top Ring Material:Iron

Top Ring Facing Material:Moly

Second Ring Thickness:5/64 in.

Second Ring Material:Iron

Second Ring Facing Material:Cast iron

Oil Ring Thickness:3/16 in.

Oil Ring Material:Stainless steel

Oil Ring Tension:Standard
Heads
Brand:Edelbrock

Manufacturer's Part Number:60179

Part Type:Cylinder Heads

Product Line:Edelbrock Performer RPM Cylinder Heads

Summit Racing Part Number:EDL-60179


UPC:085347601790

Cylinder Head Style:Assembled

Cylinder Head Material:Aluminum

Intake Valve Diameter (in):2.020 in.

Cylinder Head Finish:Natural

Combustion Chamber Volume (cc):65

CNC-Machined Combustion Chamber:No

Intake Runner Volume (cc):171cc

Exhaust Runner Volume (cc):77cc

CNC-Machined Intake Runner:No

CNC-Machined Exhaust Runner:No

Intake Port Location:Standard

Exhaust Port Location:Standard

Intake Valves Included:Yes

Exhaust Valves Included:Yes

Exhaust Valve Diameter (in):1.600 in.

Valve Springs Included:Yes

Maximum Valve Lift (in):0.575 in.

Outside Diameter of Outer Spring (in):1.460 in.

Damper Spring Included:No

Number of Springs Per Valve:Single

Retainers Included:Yes

Retainer Material:Steel

Locks Included:Yes

Lock Style:7 degree

Valve Stem Seals Included:Yes

Valve Stem Seal Style:positive stop

Rocker Arm Studs Included:No

Rocker Arms Included:No

Rocker Arm Nuts Included:No

Guideplates Included:No

Valve Cover Mounting Style:perimeter bolt

Accessory Bolt Holes Drilled:Yes

Intake Valve Angle:18

Valve Guides Included:Yes

Valve Guide Material:Manganese bronze

Valve Seats Machined:Yes

Valve Seat Machine Style:3-angle

Valve Seat Material:Ductile iron

Steam Holes Drilled:No

Oiling Style:Through head

Machined for O-Ring:No

Heat Crossover:No

Quantity:Sold individually.

Notes:Designed for non-emission 1968-73 340 C.I.D. Chrysler engines. RPM Chrysler 340 heads have chambers machined .060" for clearance with early high-compression engines. The special valvetrain in the 1970 340 T/A is not compatible with these heads. Head comes with springs for hydraulic flat tappet cams.
Sorry for pissing anyone off.
 
Without using t/a heads or tubing and offsetting the pushrods about the max you are going to get out of an x head is 284 cfm, and at that level there is a slight difference. About 12 cfm. It was explain ti me as the x head was cast with the big valve in mind so the water is farther back unlike the j ect. But remember that is at a level no one should really go. Unles your class forces you to.
 
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