A-body needs more power!

[ZEEEW]

Hello all

I have posted this question before, but with newer members...
Am going to build a warm engine for the old 1973 Dart and am considering aluminum heads on a 360, and a centrifugal blower. Also have a 68 forged crank 383 but a big block is a bit more work. Want "only" around 300-350 horse, but more is always good! 8 3/4 rear will be installed. Plan on manual valve body 727, possibly aftermarket 6 speed manual. Total upgrade powertrain cost allotment including transmission around 5-6 k.
What brand/type of heads, or other upgrades or engine combos, do you all suggest?
73-76 front ends kinda ugly to me, but plan on changing front clip because rest of car is in great shape.
Interchanging parts, k-members, some welding, all within our capabilities.

Thanks

Eric

 

[Bad340fish]

Well 350HP will be very easy without the blower for one. Here is the very easy to build combo that my 3500lbs Car went 11. 98 with.
. 060 Over 340
KB Hypereutectic(sp?) Pistons 10:1 comp ratio
Midly Ported X heads with 2. 05 Intake and 1. 60 Exh valves
Mopar M-1 Single Plane Intake Manifold
Clevlite 298* Duration . 508 lift hyrdraulic flat tappet camshaft
Holley 700CFM Double Pumper
And thats it.
Remember for that kind of times it takes the rest of the car to go with it. That same combo ran low 13. s for along time. I added a 8" Turbo Action 3800 stall converter and took over a half second off of my time!! Then ported the heads for some more time off, then I added the larger valves and got some good weather and she went 11. 98.
A friend of mine with a 360 with the same parts in it went a best of 12. 50. That motor was also daily driven for 5 years when it made that pass lol. I think I smiled the whole way home knowing i was then driving an 11 second car lol. Good luck with your ride!
Clark

 

[Bad340fish]

Forgot to Add, I ran on a Dyno jet and came up with 307hp@5700 and 375 Ft Lbs@3200. Not sure how right that was really. HP line went FLAT @ 5500. I told him to run it to 7000 but he let off at 6 for some reason. Tires were smoking after the run, he then told me it was impossible to spin the tires on the dyno lol. I like the Quarter Mile Dyno times better

 

[Shelby Griggs]

I have never built up a small block Mopar (does a 318 in a 1968 pickup count?), but my Father In Law had some killer small blocks, mostly in Barracudas. The Mopar stuff is usually seriously underrated by all of the hot rod mags. For fairly low bucks, you can put just about any Ford or GM product to shame.

My Father In Law built a 340 for a circle track car, that he had in a street car for testing. He loaned it to me one day (close to 20 years ago now), and that thing was scary. No blower or anything exotic. Built up from parts he had laying around the shop. I think one thing he did was but 270 pistons and connecting rods in, little tricks like that lower the reciprocating mass. He was ingenious, but never had much money, but sure did enjoy racing Mopars.

Shelby

------------------
2001. 5 2500 QC LB 4WD, ETH (Built 09-10-00), DEE, 3. 54 gears, Laramie SLT, Camper Special, Trailer Tow, Travel Convenience Group, Power Driver Seat, Alarm System, Remote Keyless Entry, Fog Lamps, Cab Clearance Lamps, HD Transfer Case, Bright White with a Gray Interior. Built 09-15-00, took delivery on 10-06-00, 12310 miles as of 05-01-01. Custom aluminum work body / flat bed. Coming soon: E-Brake and gauges.

 

[Chad Sheets]

The aluminum heads are pretty costly... to me. You might check Hughes Engines (www.hughesengines I think). That guy is pretty squared away on heads and cams. I have ran Indy cylinder heads, "stock" heads and Hughes heads, and the Hughes heads have made **my** engine set up run best but thats me.

The 340 blocks are getting harder to find. You can build the 360's to do the same for the same price if not a little less due to the outrageous prices for 340 blocks.

If 25 people reply to this, you are going to have 25 different combos. If it was me and I had that much cash to spend on the ordeal, I would just get one of those Mopar Performance complete crate engines ($4-5k??) and be done with it. No labor pains involved. You order it one week, get it the next and put it in. Not too radical, easy to maintain etc. Just a thought. Hope this helps.



------------------
Always ready to help!
2000 2500 Red Sport quad cab, 4x4, K&N, DDI's, straight piped, boost, pyro and fuel pressure gages, Hot Power Edge, EZ box, race transmission, Barry Grant fuel system, mean looking set of 35" tires, Snap On diamond tool box, Marine Corps window sticker, Semper Fi!

1972 340 Cuda'. Original tripple Black, 340 car w/air. Good clean car, super stock springs, Weld Prostars, shaker hood, strong 340 with a 727/4000 stahl, 4. 56... . Bombs away!
NRA Life Member
My Diesel Page

 

[Bad340fish]

Chad is right about the 25 different Combos lol. The one I mentioned above just happened to work for me, surprised alot of people as well as myself. The Edelbrock heads will not work on a 340 without custom pistons. Due to the fact the the piston comes out of the deck a little on a 340 and the edelbrocks closed chamber design prevents that from happening. They will work on a 360 though. Brodix makes a good set of heads from what I hear. Do not underate good ole X or J heads. I had mine flowbenched and they did very well for a midly ported stock head.

Going price for a good 340 block around here is $200 and yes they are hard to find. 360s are easy to find but they have a cast crank as opposed to the 68-71 340s with a steel crank. 340s also come with the Good heads(Pre 71 that is). I got VERY lucky last year and came up with a Standard Bore 340 Block and a standard grind steel 340 crankshaft for $200. . the same day I broke the crank in my car. . whew #ad
. Well thats enough of a long post, I can go on forever about small block mopars vs chevy and ford Have fun
Clark



[This message has been edited by Bad340fish (edited 05-22-2001). ]

 

[RonaldLarson]

Gotta love the 340's! What a masterpiece.
If it was me, I'd either 1. get the Mopar crate engine. 2. Wait for a crate engine offering on the fantastic 4. 7L and REALLY fly.
Ron

 

[ZEEEW]

Well, I figured having one built with the lighter alum heads would be about the same cost as a crate, but consideration has been given to the crate motors too.
Also, I have the support (encouragement actually) of the woman, she wants a six speed of course. Keeps telling me about the car at her work with a blower. And she would help pay, cant leave that out.
Dont want a high stall converter (must be streetable), so anyone out there running the Richmond 6 speed? I figure a new good running motor in a old car is cheaper and cooler than a new car anyway.
Plan on staying with dual-plane manifold, racing at the strip would just be for fun.
First choice would be 340 but, hard to find.
Figure centrifugal blower would help it with lots of power and keep low end too?

Eric

 

[Max340]

The dual plane recommendation from the Mopar engine book suggests that cutting the plenum divider down to about 3/16-3/8 of an inch will get you the best of both worlds.

A 360 will make more power with the same mods than a 340.

The cast crank in a 360 will easily take 400hp.

IF you want to go aluminum heads, look for a set of W series heads from a racing operation that has moved to the next generation W heads. W-2,5,7 are all "old tech".

When selecting a cam, realize that overlap and intake open event are more important when selecting a profile. Select cam to work with compression ratio, as both above mentioned events affect cylinder pressure and thus power.

The 8 3/4 axle will not have the right bolt pattern unless it is modified. The housing for the A-body is the narrowest, and all the axle shafts are small bolt pattern (5 on 4") wheels. I suggest that an 8 1/4" axle would be easier to find and will have the large pattern your car already has, unless it started life as a /6 car and was early production for 73.

I would not bother with a blower, it sounds like the power you want can be had without it, and it adds headache to the installation and maintenance.

Personal opinion? 360 with a decent port and port match, about 9. 5/10:1 and a reproduction 340 cam, a 268/276 grind.

However, If you want quick easy and power, the Mopar crate engines are hard to beat for value. HR mag did a comparison, and carefully hid the fact that the 360ci 380 hp Mopar engine not only made more than advertised (402hp IIRC), but also made more than the Ford 351 or Chevy 350 (which had the aluminum heads).

Post pics when done.


------------------
Y2K 2500 QC Sport 4x4 LWB
72 Dart 340
89 LeBaron GTC 2. 2 TI

[This message has been edited by Max340 (edited 05-22-2001). ]

 

[Markcuda]

Wow Gentlemen: For a minute there I thought I was on Moparts.com! Had to double check to make sure it was the TDR. After all this reading, I thought I would weigh in. I got a '69 Cuda convertible, had a 318 2-barrel, replaced it with a 360/380 crate motor from Summit $3510. It was a simple bolt in, used a few of the 318 parts. I have a 904 auto which was redone with a very nice shift kit. Had a torque converter made about a 2600 stall. Now don't laugh, I still got the little wienie rearend in, 7 1/4 - 2. 76 gears. Compared to the 318, this thing flat out hauls A$$. Mustang Cobras are a joke, the GT's I won't even acknowledge. I have a 8 3/4 with 3. 23s waiting to go in. Don't know what I'm waiting on. Then it will be flat out scary. Dollar per horsepower it is hard to beat the 360 crate motor. If you want anymore info on this combo, let me know.
Mark Smith

 

[moparguy]

This is good stuff. I suspect you guys already know , but the old LD 340 Eldebrock aluminum intake (dual plane), that was the intake to have on 340's back in the early 70's, still works great on the street and can be had for $50 or so on E-bay.

I'm still running one on the old, um, uh, stock, yeah that's it, stock 340, 70 4spd, Duster. It has the Chrysler part number, an is painted the correct street Hemi orange.

Now, I just need you'all to help get me fired up enough to spring for the new rear quarters for the 68 Barracuda Convertable so I can get it on the road. Well that, and a new carb for the Duster, the old AVS has had it. Get those two where they need to be and life would be complete, almost. Then there's the new turbo housing and exhaust for the little truck, man, there's no end to this.

 

[Bad340fish]

I have grown up messing with Small Block Mopars. From working on my 340 and my friends 360(The same setup as my 340 listed above) They seem to like alot of camshaft and single plane high rise manifolds(Strip Dominator, Mopar M-1, Victor ETC). The 360 went a best of 12. 50 and my 340 went a best of 11. 98, both daily driven 93 octane cars. But for a street motor the 360 is better IMO because of its diesel like torque lol. We even tried to kill some torque with a huge cam(Hydraulic Flat Tappet 308 duration 530 lift) But it didn't phase it at all. Now when we got 8" converters in our cars The 340 came to life(My 2. 2 60fts went to 1. 6s lol) IMO the 340 will make more HP and will love a loose high stall converter(a good one cost about $900. . trust me you get what you pay for on them) But with a 360 you can lay down rubber for as long as you want and keep a 2000 stall converter. Sadly my 340 wouldn't even spin the tires with stock converter in it lol, But you could stab it from 3000RPM and smoke them. So thats the way I see the 340 vs 360 thing. Long enough post?
From what I can tell the LD340 has been renamed the Performer RPM good manifold
Also in 1973 the A-bodies went to the 4. 5 inch pattern so your lucky there #ad
I just spent over a grand to change it over to big bolt pattern and disc brakes. I like this kind of thread. . keep it up
Clark
EDIT, Be careful going to Roller Cams lol. I installed an Erson Solid roller in my car last season, same size as my hydraulic flat tappet but a solid roller. It took . 6 off of my quarter mile times. Talk about ****** off lol. I think it would have gone back with the 4. 56 gears I stuck in but I never got to race it with them. Broke a piston(6 years out of them I was happy lol) so now its apart again. It will be better and badder with some 13:1 Ross Pistons in it this time. . sorry for the long post
Clark

[This message has been edited by Bad340fish (edited 05-23-2001). ]

 

[ZEEEW]

Markcuda, I posted this same question on Moparts also, a while ago. Most of the replies on the crate motors didnt think the quality was there in the engines, what do you think about yours? So far 360/380 is the first choice, except for the negativity from Moparts.
I have a spare 7 1/4 from the parts car so I guess it wouldnt hurt to run the smaller axle til a 8 3/4 or 8 1/4 comes along.
I dont want an engine as peaky as a race 340, want the easy tire spin kind!
I have a 72 and a parts 73, we are taking the wider bolt pattern/disc brake k member from the 73 to put on the 72, and putting aftermarket wide bolt axles in the 8 3/4 on the 72. My driver 73 is almost 100% rust free, very minor dents, so I just want to find an older style to swap the front end to mine, unless I find an older style in as good as shape as mine (doubtful). Totally stripping the parts car also taught me about the general assembly, takes alot of the nervousness out of making changes to mine.
Bumpers, drivetrain, glass, all useful internal parts have been salvaged. Drove the parts car home, engine will go in the 72 as well, for now. The 72 is little bros.
Little brother has been a bodyman/painter for about 9 years now so a very nice paint job is going to be the cheapest part, why I can spend more on the engine!

 

[Gary - K7GLD]

Being a firm believer in "bigger and MORE is better", I would take a serious look at a hemi crate engine right outta the box. Dunno about relative physical size problems, or weight balance, but if you could stuff it in there, that baby would HAUL!

Best similar action I have done, was a B&M blown top quality Chevy 350 into a '69 Datsun pickup - it had a heavy duty GM 3-spd OD and Ford 8" differential. It was all painted up, upholstered, and from the outside, looked pretty stock...

Nothin' like pulling out around to pass some slow driver at about 25 MPH in second gear, and then burning LOTS of rubber all the way around them - sure wakes them up!

But I was younger then - only 55... #ad


------------------
http://community. webshots.com/user/davison71 Early '91 250, 727 AT, 307 rear... 108,000 trouble-free miles... Banks Stinger exhaust, intercooler... US Gear OD... Tweaked pump, upgraded radiator... Power Shot 2000 propane system... Mag-Hytec double deep A/T transmission pan...

MORE than a match for every new PS Ford encountered so far...

"Dura" WHAT? NOW I know where all those recycled beer cans go...

 

[Bad340fish]

I would think for as well priced as the crate motors are that you would see more of them really. For some good all out tire frying power a 10:1 360 with the "purple shaft" camshaft and a performer RPM are gonna be hard to beat, especialy if you throw some of those aluminum heads on it. Should be cheap to build also, minus the heads
Clark

 

[Max340]

Mark, the 3. 23's will really wake up your car. Swap out that 7. 25" as soon as opportunity allows, as it will eventually loosen up and break.

Moparguy, nothing wrong with a stock 340. If its all original, take pics and notes, the info may be valuable to a restoration later on. Rear quarters for the Barracuda are available from Jims Autoparts and Year one. Jims is a bit lower in cost.

Gary, the Hemi's are a bit pricey ($10-15k) and are a tough project for an A-body. Still, its a heckuva car when done.

Bad340Fish, I agree on the 360 combo, its simple, very friendly to drive and likely makes real good power, probably close to or just over 400hp.



------------------
Y2K 2500 QC Sport 4x4 LWB
72 Dart 340
89 LeBaron GTC 2. 2 TI

 

[Bad340fish]

The 360 I spoke of above went 13. 30 with a stock converter and street radials. At the time it was nothing special. KB Hypereutectic pistons(Very Very good piston for the SBM, makes it a quench style chamber) about 10:1 with stock X heads and holley 700CFM. Easy build and a killer tire fryer. That time was with 4. 10 gears but it went 14. 90@100 with 2. 71 gears lol in a 71 charger
Clark

 

[Wayne M.]

Hey ZEEW, One thing I really reccomend is to call and get the Mopar Performance Chassis and Engine books, AKA the Bibles. There you will find all the little info about all the swapping you would ever want to do, except for putting in a 6 speed. For that scour some recent Mopar Magazines for a special issue dealing with that swap, there is a guy out there who offers a soup to nuts kit to do the deed (not cheap). As far as putting in a 8 3/4 axle in place of a 7 3/4, you're gonna need a driveshaft, and thats why I say to get those books because the chassis book will give the exact length shaft you need.

If you want to see my car, goto http://www.moparts.com/moparts/picture/race/race.html and look for the brown Duster. Mild 340, full manual 904, a tight streetable 8" converter, 4. 88 gears = 12. 25- 12. 60 Quarters all day long.

------------------
'92 W250,3. 54,auto,reg cab, raven hi top cap, tach,boost,transtemp,pyro. 16cm housing.

1971 Plymouth Duster 340 Autumn bronze, Black buckets/console. 8 pt roll cage, other racing mods. 12 second bracket racer. BOMBing not done yet!!

1998 Durango 5. 2, P. T. , 3. 92, Chillipeper Red, All STOCK

 

[Bad340fish]

Man, you drive on the street with 4. 88 gears?? I thought my 4. 56s were bad lol. I just went from 3. 91s to 4. 56s, now with this new motor I think I am going to have to go back #ad


BTW I have a set of 6 old slotted mag wheels for the small bolt pattern, decent tires and one of the sets of rears has VERY new MT 26x8. 5" Slicks with tubes. I need to get rid of them
Clark

 

[Chad Sheets]

Mopar Perf also sells short blocks. You can get a 360 short block with the 292 purple stripe cam and flat tops at zero deck clearance for about $1000+/-??. They sell them in 10:1, 10. 5:1, and 11:1 if I remember right. Not too sure on the particulars, but I know they are selling them.

I also heard they were going to start selling a 340 "restoration" block. Might give that a try if any of you are dead set on the 340.

------------------
Always ready to help!
2000 2500 Red Sport quad cab, 4x4, K&N, DDI's, straight piped, boost, pyro and fuel pressure gages, Hot Power Edge, EZ box, race transmission, Barry Grant fuel system, mean looking set of 35" tires, Snap On diamond tool box, Marine Corps window sticker, Semper Fi!

1972 340 Cuda'. Original tripple Black, 340 car w/air. Good clean car, super stock springs, Weld Prostars, shaker hood, strong 340 with a 727/4000 stahl, 4. 56... . Bombs away!
NRA Life Member
My Diesel Page