In need of an education..340 vs 360.

-
The reason bill jenkins name up is this statement (No replacement for displacement) if that is so I could build a 800ci engine and be top dog in pro mod.They have them in pro mod and 600ci engine are beating them all the time.And yes I am serious this was told to him all the time and he did it to prove them wrong.prostock didn't take him serious until he startied betting the pants of everyone.Also he was not the onlyone there ware many that showed what you are talking is wrong.One thing i will say is all of my 340,s were bigblock killers no matter what body you had them in.And never had a 396 out run them nova,camrao or chevelles.Like I said the racers in my aera mostly were mopar guys(use to be chevy) and 340,s was the cause of it.To guys had dusters one a340 and one a 360 both engines were built the same.the guy with thought he had the edge with the 360.The 340 beat the pants off the 360.Maybe you have a super 360 the one they never madeAlso the most ridiculousness ststement that was made was yours. Mark
Lonewolf3165 said:
After reading this thread I just got to a point with all this ridiculousness here I couldn't stay out of it. BILL JENKINS! Are you serious? Your talking about aseriousengine builder & innovator who was at the top of his game vs so many also rans at the time. It wasn't the multi-millionaire only class that it is today. Also the Pro Stock class at that time had weight breaks based on cubic inches, so there was an advantage to running a smaller engine/ lighter car combination. Remember Glidden & his Plymouth Arrow? Weight breaks is why he changed over.
If you seriously think a 340 could take a 396 in stock form you need to check into rehab! In car of similar weight & size(camaro/ nova) the 396 made more power in EVERY version produced so the power to weight being even close it would beat the 340. So yes it probably came down to bad drivers.
The 340 is cool if you are into nostalgia. I can say this; Horsepower is a by product of torque. Torque is easier to produce with longer stroke & more cubic inches. A smaller engine will rev higher to produce the same horsepower out of necessity. I've built them both. If I had my choice I'd build an early 360 block(same core as a 340 BTW) & enjoy the extra power it produces at lower RPM. Even if I disappointed the crowds because of it! Lower ET slips cure that rather quickly!
I'm not a 340 hater or a 360 lover. But the facts are what they are.
No replacement for displacement!
Click to expand...
 
dartcuda1 said:
I call foul! When Pro/Stock started in 1970, Mopars dominated. PERIOD! Same thing in 1971. And there were only 5 or 6 National events back then, not like it is today. I think it was between the 1971 and 72 seasons when the Mopar guys built their new pro stock cars according to the rule book. They didn't know that Wally Parks had told Jenkins to build a car to beat the Mopars and he would see that it got through Tech. So Grump built a light weight tube chassis style Vega that was totally against the NHRA rule book. Sure enough, it passed tech. And, in order to "equalize" the field, AKA Chevy must win to satisfy the masses, the lowest common denominator, the Hemis were required to carry more weight per cubic inch than any other style engine and they kept on adding weight until the Mopars absolutely were un competitive. This was NOT between seasons, the weight breaks were changing between the National race events. And the crowds went wild, and the Mopars simply packed up their stuff and left as there was no way for them to even win a hot dog. Simple math, more weight per C.I. = losses.

It's painfully spelled out in the book "We Were the Ramchargers" and vintage car mags but I was at every Indy Nationals from 1970-1975 and saw it happen year by year. (Used to camp out in the Drive-In theater across the street and go to the races Friday through Monday) In the book, they say that Wally Parks actually apologized to the Mopar guys decades later and admitted he had screwed up. Same story in Nascar.

Oh, and I'll take a 340 over a 360 just because.
Click to expand...
 
dartcuda1 said:
The reason bill jenkins name up is this statement (No replacement for displacement) if that is so I could build a 800ci engine and be top dog in pro mod.They have them in pro mod and 600ci engine are beating them all the time.And yes I am serious this was told to him all the time and he did it to prove them wrong.prostock didn't take him serious until he startied betting the pants of everyone.Also he was not the onlyone there ware many that showed what you are talking is wrong.One thing i will say is all of my 340,s were bigblock killers no matter what body you had them in.And never had a 396 out run them nova,camrao or chevelles.Like I said the racers in my aera mostly were mopar guys(use to be chevy) and 340,s was the cause of it.To guys had dusters one a340 and one a 360 both engines were built the same.the guy with thought he had the edge with the 360.The 340 beat the pants off the 360.Maybe you have a super 360 the one they never madeAlso the most ridiculousness ststement that was made was yours. Mark
Click to expand...
So let me get this straight. You're saying a car that weighs about the same, with 30-50hp advantage on the street can't beat a 340? And all things being equal, heads, compression, cam, intake, carb etc,a motor with 20 cu. in more displacement wont make more power? And the fact that Bill Jenkins cars weighed a lot less than the Hemi cars in P/S at that time doesn't matter? If Grumpy could make the same amount of power in the Small Block as he could have with the Big Block wouldn't he have stuck with that when NHRA removed the weight breaks?
Kinda defies all the logic & real world data that engine builders & racers have relied on for decades.
Yeah, I guess I'm just the one making ridiculous comments here.

"Never let the facts get in the way of a good argument"... - Ronald Reagan
 
..i remember in 1969 watching numerous times the stock class final come down to 2 340 Darts at our local track.
..stock they were only 275 h.p. yet they routinely beat higher h.p. cars and some with better h.p. to weight ratio.
there is a lot more to racing than h.p....it's the total package.
an older local racer often tells of the many cams he had tried that produced bigger h.p. numbers but would never et very well.
both 360 and 340 are excellent engines and would be built a bit different for best results.
 
340 block advantages
-can be bore bigger than most 360
-small main bearings

360 block advantages
- cheaper most times


When we talk about engines we always leave out the rest of the car a 400hp 225/273/318/340/360/408/440/500 will produce similar times if put into the same chassis if weighted equal and if each had the right gear and stall speed for each engine.
 
Wow you guys sure got ugly.... :). You guys have indirectly helped me out, yet left me still wondering somethings. I did learn that the 340 piston sticks up above the deck. So that is where they got there compression. Every stock 360 I have ever seen are waaaaay down the hole. Like I said originally, I have been mentally building this 360 for years, can damn near recite the specs and parts list. This 340 was just an opportunity that popped up, and never studying them or even looking into them, I was lacking. So to elaborate a little, I am going to drive the Duster in say... A rather spirited manner, lots of cornering, up and down shifting, hard braking. Yet short shifting around 5500- to maybe 6k, 6200!if I blow a shift or get distracted. However it is also gonna be a DAILY DRIVER, with a/c, roadtripper etc. now prior to this post the only thing I knew of 340's was hype, reputation, and unicorn like mythical tales. They also have a wicked cool factor!!! For years people have asked what motor is going in my car? When I replied 360, you could just about watch the eyes glaze over in the uninformed. Lately since the purchase of my 340, EVERYBODY lights up!
340 pros: forged crank(not certain I really need it, but it is comforting.) TQ, the original one to the engine! Clean inside, evidence of low mileage, or exceptional care. 10-1 plus compression. Cons... Gonna need to work the valve seats for todays fuels. Could in theory give it a ring bearing, gasket , cam and a paintjob. However it will also need a Milodon road race pan and windage tray, but either engine will need that! The 360.... Well it will need new flattops, new eq heads, unless by some stroke of luck my magnums on the shelf are good. All the basic machine work to put my frankenstein stock of 360 parts together. In the grand scheme of things... I do believe the 360 even in my desired mildish tune will be the better performer. My 340 will be cheaper and quicker to put to use sooner than later. The sale of the 340 will not be enough to make up for the budget shortfalls left with the 360. One last question. I made an assumption that the 340 heads will need hardened seats installed? Yes or no? Figure best gas,pump premium 91 octane. A flat topped mag headed 360... All day long! How about this 340?
 
71dusterdan said:
Wow you guys sure got ugly.... :). You guys have indirectly helped me out, yet left me still wondering somethings. I did learn that the 340 piston sticks up above the deck. So that is where they got there compression. Every stock 360 I have ever seen are waaaaay down the hole. Like I said originally, I have been mentally building this 360 for years, can damn near recite the specs and parts list. This 340 was just an opportunity that popped up, and never studying them or even looking into them, I was lacking. So to elaborate a little, I am going to drive the Duster in say... A rather spirited manner, lots of cornering, up and down shifting, hard braking. Yet short shifting around 5500- to maybe 6k, 6200!if I blow a shift or get distracted. However it is also gonna be a DAILY DRIVER, with a/c, roadtripper etc. now prior to this post the only thing I knew of 340's was hype, reputation, and unicorn like mythical tales. They also have a wicked cool factor!!! For years people have asked what motor is going in my car? When I replied 360, you could just about watch the eyes glaze over in the uninformed. Lately since the purchase of my 340, EVERYBODY lights up!
340 pros: forged crank(not certain I really need it, but it is comforting.) TQ, the original one to the engine! Clean inside, evidence of low mileage, or exceptional care. 10-1 plus compression. Cons... Gonna need to work the valve seats for todays fuels. Could in theory give it a ring bearing, gasket , cam and a paintjob. However it will also need a Milodon road race pan and windage tray, but either engine will need that! The 360.... Well it will need new flattops, new eq heads, unless by some stroke of luck my magnums on the shelf are good. All the basic machine work to put my frankenstein stock of 360 parts together. In the grand scheme of things... I do believe the 360 even in my desired mildish tune will be the better performer. My 340 will be cheaper and quicker to put to use sooner than later. The sale of the 340 will not be enough to make up for the budget shortfalls left with the 360. One last question. I made an assumption that the 340 heads will need hardened seats installed? Yes or no? Figure best gas,pump premium 91 octane. A flat topped mag headed 360... All day long! How about this 340?
Click to expand...

if you are rebuilding a 360 are you going to buy pistons that stick WAY DOWN in the HOLE...????
build the faster engine which is the 360...and put a 340 decal on it........LOL

might is bigger then your...no its not...yes it is..no its not...lol
 
I didn't see anybody gettin ugly. This has been a good discussion. I think somebody needs to put their big girl pants on.
 
the 340 vs 360 threads usually turn into a mud fight...lol...but it is in the virtual world...
 
There is a point hear and of course you missed it.And yes you are making ridiculous comments hear.biuld your 360 and go 340 hunting you will get your nuts handed to you sooner then you think. Mark
Lonewolf3165 said:
So let me get this straight. You're saying a car that weighs about the same, with 30-50hp advantage on the street can't beat a 340? And all things being equal, heads, compression, cam, intake, carb etc,a motor with 20 cu. in more displacement wont make more power? And the fact that Bill Jenkins cars weighed a lot less than the Hemi cars in P/S at that time doesn't matter? If Grumpy could make the same amount of power in the Small Block as he could have with the Big Block wouldn't he have stuck with that when NHRA removed the weight breaks?
Kinda defies all the logic & real world data that engine builders & racers have relied on for decades.
Yeah, I guess I'm just the one making ridiculous comments here.

"Never let the facts get in the way of a good argument"... - Ronald Reagan
Click to expand...
 
I like my 340. I wouldve gone with the late 80s/early 90s LA 360 roller block had I known about them at the time I was looking for a motor and if I hadnt got my 340 for dirt cheap ($50). That said, nothing is original in/on my 340 other then the block and timing cover.
 
If the 340 can get away ring job save some dollars than its an easy decision you'll be happy with either 340 gonna make the same HP just a little further up in rpm probably 200-500 rpms. 340 just need a little more stall and gear than an equally built 360. The valve seats with unlead gas shouldn't be a problem especially with a summer play toy.
 
How much will it cost to get the 360 to the HP of the stock 340 $1,000.Better heads,cam,intake and carb and headers?You can rob the 340 for all these parts but why do that when you have the 340 complete sitting there.The stock 340 pistons are heavier but they are stronger than the 360's and you are going to be doing road coarses right.I say freshen up the 340 for around $200-$300 and sale the 360 to one if these guys.Also the 340 should run on pump gas in stock form.To add I just bought kb pistons .04 over and 650HP I beam scat rods for my 340 and they weigh 1/2 pound lighter than my stock bore stock 318 pistons so if piston weight is an issue there is a solution.And my piston and wrist pin weighed 716 grams.I have nothing against the 360 but if you have to spend money just to get to a stock 340's HP its a no brainer.I'm more of a cicle track guy than this strieght line stuff so I look at what an engine will do on the road and the higher rpm is more desireable when a guy comes along side you at 50 mph.Just my view.
 
BTW I'm putting my 6 pack on my car,not for better ETs but for the wow factor.
 
This is an interesting thread. I have a 340 Duster I drag race. 340 has been raceed since the 70s. It runs 11.50s-11.70s. Have to rev the hell out of it. When its time and I can afford Im looking for more cubes.
 
Build what you want and whats in your budget, I have a 408 in my H code duster with 340 decals and I'm happy, who cares what the cool crowd thinks.
 
340.....360........ Just meet in the middle and toss a 350 in there and piss 'em all off
 
You must log in or register to reply here.
-

Back
Top