360 build ????s

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MoparMcK

MoparMcK

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In the near future i will be swapping my 72 Demon from a 318 to a 360. I just have a few questions on some pointers.

Info on the car, 4 speed trans, 8.75 rear with 4.11ish gears. I will be using the Edelbrock torker II 340 intake off the 318.(unless a better option is out there) That is about it. I have researched the specs on the intake also. Street driving with some fun at the track.

I have always been a huge fan of the Mopar Purple Shaft cam 284/484. So that is the idle/sound i am looking for. I know they are good cams and that there are better cams out there also. Just learning yet and not sure exactly how to read all the numbers.

The 360 I will be starting with is a low mileage 70s era(not sure on exact year). So will have stock rotating assembly. Now for the questions...

- What is a good applicable cam comparable to the 284/484?

- I want to change the heads. I have read a lot about "J" heads and "X" heads. What is a good iron head to go with? One of these fit the build?

- What would be a smart carb size to go with? The intake says a 600-800 cfm. i would like to narrow that down to a more exact cfm.

I know the smart thing to do would be tear down the whole motor and start fresh and what not. This is a budget build to enjoy for a few years. Then as I save and buy parts it will be bumped to a 408 stroker. Right now just want to have a fun beast of a motor to mess around with.

Thanks for any and all advice and criticism.
 
Well I bought some 72 "J" heads today. They have been ported and polished. New valves and springs installed. Springs are good to .550 lift the guy said. Should be a good start to my minor build.
 
A stock 340 intake is head and shoulders better than your Torker. Jes sayin.
 
Ditto on the torker.
284/484 cam works well .
Motor might need a bit more compression .
Thin head gaskets can help a little .
I would get an air gap .
Carbs can very I would star with a good 650 and go from there .
I have ran a 750 on a 340 with that cam, but I had 10.5:1 cr .
Best of luck !!
Jim
 
Get some headers, edelbrock air gap or ld340, a nice cam built to your specs of the car 500+ lift range, a 750 double pumper holley and those j heads ����
 
Not much wrong with what Jim ^^^ said. :)

Intake wise, the "big" dual plane's (RPM/Stealth) are so good today, it's hard not to recommend one of them. That said, I wouldn't necessarily rush a Torker "II" into door stop duty, considering how forgiving a 4spd/4 series gear will be on the street?

Carb wise, I'd go right to a manual secondary unit (DP), and a 750 should give the best overall compromise. But, if by chance you do keep the single plane intake, I personally like to stay a little smaller on the street with a lg. plenum intake.....650ish has worked for me in the past...

As far as cam choice, I like to focus on "lift" with modest compression and stock heads. I wouldn't rule out the Comp. 275HL for a build like this as long as the new springs are up to the task..... http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=631&sb=0.


Just a few thoughts out of dozens & dozens of possible combo's...:D. Bottom line...Be safe, Have fun, and row those gears baby. :thumbrig:
 
My 360 has ,20 over ld340 intake, 340 J heads 202 valves 280 474 Purple MP cam ,headers,electronic ing,timing 20@ idle 16 mec, 323 suregrip gear,727 with a 2200 stall,600 holley,it should have the 750 back on this combo screams and light the tires big time.:burnout::burnout::burnout::burnout:
 
Airgap or ld340 for and intake..Mopar cams are out-dated put it back on the shelf..look at the Lunati voodoo cams i've run a couple of them with great success..
 
Awesome! Thanks for all the input and keep it coming. It kills me not knowing and understanding all the different variables. So all info is appreciated. The intake may go on for starters unless I find one in the mean time. The cam is the biggest thing I am on the fence about. The car will have a ton of street/highway driving and a trip to the strip round six times a year at the least for the local Mopar races.
 
Also, the heads I bought were on a 340 storked to a 373. He said he put a 360 crank in, had a .490/.502 cam(brand unknown) 273 adjustable rockers, 9.75-1 comp. Ran 420 hp on the dyne. Idk if that was at the tires or flywheel. He did not say the car it was in. Just that it was a full steel bodied car. Nothing lighted up and ran 12.40s in the 1/4. Just sharing what I was told by him.
 
If you have the 484 cam and want to run it, go for it. The cam works pretty good and can easily put a combo in the 12's even high 11's without issue. Depending on compression ratio, advance the installed centerline as far as 100-102 area. DO NOT use the 114LSA 484 camshaft.

The torker II isn't my favorite intake, prefer and Air Gap/RPM/LD340. 4 Speed will cover a lot of the ills. If it was an older torker 340, straight to the smelter!

I'd put a 750DP on it. Plenty of carb to run hard.

Don't get caught up in the x or J head stuff. The heads from 68-76 are essentially the same with minor variances. If the heads you have are ported, did you get a flow sheet?
 
No I did not get a flow sheet. I saw these at the swap meet and stole them IMO. With knowing I need to update the springs on the current heads anyway and not knowing what kind of heads are on the motor. I bought them. In time I will upgrade to aluminums heads but this is a starter motor to have some fun.

What is the main flaw in the Torker II? The RPM band or flow ratings or??? Just curious.
 
Run the mp cam. My 340 dart ran a best of 13.15 with the mp 280 cam. Switched to a 276 voodoo best time was 13.13 Not what I expected. Maybe the 280 just fit my combo better.
 
I agree with cracked, post 11.
Especially the part about the 4 speed covering a lot of ills.
And with 4.11s, the combo can be almost out to lunch and still work.

Personally, while I love the idle of that cam, I wouldnt use it. Its like a little dog with a mean bark.With the low compression of the oem 360, you really need a special cam. I would pay extra for it.IMO, You need a short period cam, with a fast rate of lift and lots of it, to go with those new heads, otherwise you will be leaving a lot potential, untapped.
Wait until the engine is on the stand, and the heads are off, and you can measure how far down the pistons are, before you finalize the cam choice.Then calculate the exact compression ratio. Take those measurements, along with the .550 max-lift spec. and call your favorite cam-grinder.Specify a FAST-RATE, designed for the Mopar.904 lifter, and spec'ed to keep the Dcr up.
In this way, you may find that the 4.11s can be swapped out for 3.55s, which will make your ride so much more pleasurable,as it can be driven every day,everywhere,all-the-time; instead of being a weekend-warrior, big-bark-little-bite.
 
So I have done a little reading. The best compression ratio offered for a 360 was in 72 with 8.8-1 running a 2 brrl. Otherwise 73-74 is 8.4-1. the websites I read this off of did not show anything for after 1974.

My question is what does a guy have to do to get the compression up?

As stated above it is a 70s era 360. Will be the stock rotating assemby. I have a set of J heads that have been ported and polished. (idk flow stats) They have .550 lift springs. I will be upgrading the cam. I like the purple shaft 284/484 but am still researching. Unless I come across a different intake I will be using my Torker II for now. I currently have a edelbrock 600 or 650 cfm. Idk if that will change yet.

Thanks for all the info so far!
 
Sell you my 410 stroker with 600 miles on it. Will be going another route with car. Making into daily driver with EFI 6.1 hemi
 
Fst73_410 said:
Sell you my 410 stroker with 600 miles on it. Will be going another route with car. Making into daily driver with EFI 6.1 hemi
Click to expand...

Thanks but I don't have those kind of funds. This is just a little fun throw together. Then in a few years build from there.
 
Short of stroking the 360,there is only one way to increase the STATIC compression ratio, and that is to reduce the combustion chamber size.
There are however several ways to do that, none of which are cheap.

There is another way to get some performance, and that is to increase the DYNAMIC compression ratio. And that is where the custom cam comes in, that I earlier mentioned. It'll cost you a few bucks more than an off-the-shelf cam,but if chosen carefully, can make your stocker scoot pretty good.

edit
You will need a short period,highlift,fast-rate-of-lift cam,specifically designed for the Chrysler .904 lifter, and with an early closing intake valve, to get your Dcr up. You may have to sacrifice some rpm. That means it will be down on high-rpm power. A bit. But it will still make tire-frying, out-of-the-gate torque. I can almost guarantee it will be fun.And you said"Street driving with some fun at the track".
In fact, for street duty,I'll bet you will be swapping those 4.11s out in a hurry.You likely wont get into the 12s with it, but 13s should be pie.
 
AJ/FormS said:
Short of stroking the 360,there is only one way to increase the STATIC compression ratio, and that is to reduce the combustion chamber size.
There are however several ways to do that, none of which are cheap.
There is another way to some performance, and that is to increase the DYNAMIC compression ratio. And that is where the custom cam comes in, that I earlier mentioned. It'll cost you a few bucks more than an off-the-shelf cam,but if chosen carefully, can make your stocker scoot pretty good.
Click to expand...

I will look into this a bit more for sure.
 
Just read right through this and I'd agree with the later posts that note that the 360 is a low compression motor, so be careful not to over cam it.
might be an odd suggestion, but maybe a Hughes Whiplash cam with that low compression? No convertor to worry about. Could be fun.
I built two 360 motors, one low comp and one higher and ran XE262 and then XE268 cams in them.
The 262 cam is quite small but really helped with low down torque whilst the 268 liked the revs higher up. Always a trade off I guess.

Good luck with 4.1 gears. I had 3.91 :banghead: and pulled them pretty quickly for 3.55s:)
 
I run the 280/474 cam sounds ok wish I used the 284/484 sounds meaner! I use the holley strip dominator, 3.55 gear, thermoquad and auto trans. This combo seems to do well for me. I suppose you wanting to do the 484 cam & j head will be just fine. Tuning will get the best out of your combo.
 
Ok so maybe changing things up a bit. A buddy has a 360 block .040 over. Keith Black 107 Hyperutectic pistons with stock 360 rods. Full floating pins. I was told this would help raise the compression to roughly 9.5-1 possibly a little more?? Then I would still be using my J heads.

Thoughts on this application vs using the stock rotating motor previously mentioned?
 
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