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  #1  
Old 12-14-2001, 12:10 AM
TOYZ28 TOYZ28 is offline
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Location: Marshall MN
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Question 340vs360

Wanted,
I am new to this website,but looks like the right place to be with
my new adventure.
I have a WISSOTTA SUPER STOCK, for those of you that are not
familierwith this car,It is a poormans latemodel in that you
have to run 9" ford rear end no lift bars and stock stub,which can
be mounted on a old late model frame and bam....there it is
My question is: I want to run a mopar in it and I am thinking a
340 would be my best bet since MOPAR spent considerable resources on what they wanted for a performance small block and
360 to my knowledge has never been a performance motor in MOPAR eyes,Is this correct or am I wrong? I can't stroke it,or
polish,port heads nor can it have dome pistonsand certainly not a aluminum intake,but could be cast . 4412 holley2bl on top and gas only or E-85.
Any thoughts would help,But please don,t tell me to go back to chev,anybody can do that.
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  #2  
Old 12-14-2001, 10:47 AM
I8URACING I8URACING is offline
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Location: Dickinson, ND
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Smile 360

I think that the 340 or the 360 would be a fine for the Wissota Super Stock. I would lean towards the 360 because they are more readily available.

I made a Wissota Street stock motor using the Magnum heads and zero decked KB107 pistons. This combo had compression at about 11 to 1 and had good quench.

I think this would make an excellent base for a Super Stock. I used stock rocker arms but if you are going to use a solid lift cam you will need to use a Chevy style stud mount set up. You will need to use AMC type lifters and oil through push rods.

I think the Magnum R/T heads would be legal to use. These would give you much better flow.


340king made a Super Stock enging out of a 360 using Magnum heads. He seemed to think it made good power for the class.

If you are going to spin the motor over 7000 RPM, Sanborn has some good info on oiling mods.

I hope this helps.
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  #3  
Old 12-14-2001, 11:34 AM
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cageman cageman is offline
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Does A Dodge still have to bolt weight onto the midplate in supers? I know that they did a couple years ago. Every dodge super I have ever seen was fast and there is clearly an advantage to running one. What kind of car do you plan on running?
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Old 12-14-2001, 03:07 PM
jelsr jelsr is offline
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Smoky said the closer to stock you have to run the more important displacement becomes. I think the 360 would be better since it is more of a "grunter" and would probably put up with the 2bbl better than the 340 which usually turns more R's. The 360 is a popular IMCA Mod engine around here and seems to be quite durable if the R's are kept out of the stratosphere. I think Mopar is now offering a "racing" 2 bbl manifold in cast iron for the SB's. The head of choice for the mods are the late "swirl" type, and supposedly good for 30-40 HP over the early 340/360 heads.
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Old 12-14-2001, 05:11 PM
TOYZ28 TOYZ28 is offline
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Thanks to you guys for your help. I'm surprised at the results.looks like 360 is taking the edge.
Yes it is true that to run a 360,you need to be prepaired to bolt 40lbs on the midplate. 2700lbs total. I'm going to run a affordable chassis this year since I like the way they think. I am curious to hear more about AMC?chev bolt solid cam adjustable stuff. I thought magnum stuff woudn't
exchange with pre mag stuff.
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  #6  
Old 12-21-2001, 11:57 PM
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daren44 daren44 is offline
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Default I'd go 360

My experience is that the 360 is the better engine. The 340 has a shorter stroke (3.31 vs. 3.58) and is therefore not as torquey as the 360. Had a friend who blew up his 360 and didn't have time to fix it before a big race. Switched to a 340 he had as a spare and he was way slower. You lose cubes and stroke. A 340 has to turn more rpm's. Plus, 360's are more plentiful, and therefore cheaper to build. Just my 2 cents.
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  #7  
Old 12-24-2001, 05:56 PM
340king 340king is offline
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Default Balance

The thing to remember is that when you add wieght to the front of the car, you need to add just as much to the rear to keep the car neutral. That means that you will have to add 80 lbs of non-functional weight just to be even with the Bowtie Brigade. Add to this the slightly heavier engine and it all is too clear that the rules need to change. The only solution I can see is to run a 340.

The rules are also bent around stopping a 340. This is done by limiting to flat-top pistons that cannot come out of the deck. Stock 340 slugs come out .018"±, even though they are flat-tops. This is meant to keep the Mopar engines out of competition, since they never used to have a good closed chamber head available.

What I did was to use a Mopar Performance Short Block and add some Magnum heads. This was no small feat. As you have aluded to in your post, a cast intake is needed. We had to re-align the intake bolt holes in the heads to the pre-magnum 6° angle. This required 1/2" pipe plugs and then a Serdi head mill to put the new threads in at the correct angle. The new R/T heads have a thicker intake mating area that could be directly machined, not to mention 20+ cfm of more flow. I don't know if they are legal.

As for the rocker arms, I helped design and build a rocker shaft support stand that utilizes the early factory style of shaft rockers. This allowed me to use the 273 rockers. There were a few hurdles to overcome here also. It takes T&D adjusters, grinding some pushrod room in the heads, old style valve covers, AMC lifters and Chevy pushrods. By the way, I can build the stands for about $150 on a small production run. They are CNC machined tool steel.

As for what I think would work best, 340. I can make up more than enough power to carry the lesser weight. These cars are separated by less than any class out there in my opinion. Handling by far is the most important aspect in the equation. The engine I built ran pretty good from what I could see, but the driver wasn't that experienced and had trouble keeping in the groove. The last night I watched him race, he jumped the cushion 5 times in the heat race. I don't think one of Sanborn's engines could've helped at that point (just kidding).

Engine selection changes with tracks also. If you run on a consistently tacky track, then the extra cubes will probably pay off. If you go dry slick before the heats are over, then handling is more important and anything much more than a 5hp Briggs and Stratton will suffice under the hood.

There was about a $5,000 investment to put this thing together. One thing that I would definitely change is the Mopar short block. It wasn't worth the coin and needed major machine work prior to re-assembly. As stated before, 340's are hard to find and that has to be factored into the equation. I would personaly like to see a 340 out there, as I think it would be a great superstock engin
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