360 build !help!

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Bmatetic

1971 duster build
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hey guys i have got my hands on a 360 for a dart im doing and im looking to make it a 40% street 60% strip without getting into the bottom end just wondering if anyone has any build ideas specs and reasonable reachable numbers to get out of it.
ps. this will be a pump gas build thanks.
 
What year engine.....Is this a LA 360 or a Magnum? The real difference would be the heads & the available roller cam with the late LA or Mag.

While different, a 400+ streetable, pump gas engine is easily within reach.
 
its a 79 la 360 pulled from a camper and thats always been a queston of mine whats the differences in a magnum? thanks
 
Better metallurgy, roller cam, serpentine belts, more power stock, 200k+ zero bore wear, huge lifespan, the list goes on and on.
 
My 360 is getting ready to go to the dyno and I'm shooting for close to 400 hp. It's very easy to do and there is pretty much a cookie cutter parts list for these motors.

750 dp carb.
Performer rpm or air gap
Eddie heads or reworked iron heads with 2.02/1.60 valves
A decent cam...mp .484 lift cam for me.
Some kb 107 pistons
And bore it .30 over.

With the right head gasket and other tweeks you can play around with your compression.

I don't know how much the boring out helps but I needed it. It's going to cost a few thousand dollars but speed cost. Good luck!
 
I was think the eddie heads but the rumor is the victor heads for a sb are coming out in april and i might wait and get me a set of them .
 
PoisonDart74 said:
Better metallurgy, roller cam, serpentine belts, more power stock, 200k+ zero bore wear, huge lifespan, the list goes on and on.
Click to expand...

Is that in regards to the early LA or the Magnum? I'm assuming the Magnum.
 
I see you put out some feeler's for a set of Eddy heads. You're on the right track. Heads and cam is where you'll make your power, along with a 1 3/4" primary header in my opinion.

I should address the "stock bottom end". I assumed you meant that while keeping it a "stock" low compression build, you were still going to go thru it and not just bolt parts on to a 35yr old short block???

Meaning, if all the stars align and it's in great shape.....The minimum I would personally do is...
A thorough cleaning.
A minimum deck cut to flatten them.
Cylinder hone with a Torque plate.
New cam bearings.
Polished crank.
Good main and rod bearings with proper clearance.
Recon rods with good bolts.
File fit rings.
A new stock vol/press oil pump and pickup.

A short block build like that, while not top of the line by any means, would be my minimum since you want to run the track close to 60% of the time. The savings would come from no boring, pistons or balancing. Only you can decide how far you want to go?
 
Yea the bottom end would be gone threw like you said I just wanta see what I can get of of the stock rotating assemble ;p
 
anyone have a cam spec i should be looking for ill be running edelbroke rpm heads and all rpm fuel delivery items 750cfm carb
 
In general terms, your best bet is a high lift (to feed the Eddy's) and a moderate duration (to keep the cylinder pressure as high as possible). Most cam companies have some off the shelf grinds that fit that bill. There's always the custom cut option as well.

Something to consider also is what rocker assembly you will use, as the required spring designs/pressures for some of the bigger cams will start to exceed the capabilities of stock stamped units. Then there's the 1.5 vs 1.6 ratio consideration.

I'll nose around a little and maybe post some cams that are along my lines of thinking...
 
alright that would be a big help and for the ones that will requirer rockers
thanks matt
 
Seeing how you said the majority of use would be the track and some weekend street use.....something along these lines is what I'm thinking.....

http://www.summitracing.com/parts/hrs-710581-10/overview/make/plymouth

Assuming you want to stay with a hydraulic flat tappet.....I like something in this range. The lift is good and the split duration will help flow on the exhaust side with a full exhaust system. Keep in mind that this type cam probably requires springs that exceed the stock Eddy's for maximum performance, and i would only use it with a upgrade to a good 1.5 ratio roller rocker. Also this is just one of many possibilities.

The other issue is that the entire combo will have to be somewhat coordinated, meaning rear gear ratio, tire diameter, and a decent torque converter.

I've just scratched the surface here.....Putting together a real nice total combination is definitely not as easy as it looks. :D



P.S. Now that we're getting the ball rolling, I know many other opinions will come about.....and that's a good thing.
 
haha yes it is lol. i prolly be running 391 gear with a 20-25 tall tire and a 3500 stall in a 727
 
OldmanRick said:
Seeing how you said the majority of use would be the track and some weekend street use.....something along these lines is what I'm thinking.....

http://www.summitracing.com/parts/hrs-710581-10/overview/make/plymouth

Assuming you want to stay with a hydraulic flat tappet.....I like something in this range. The lift is good and the split duration will help flow on the exhaust side with a full exhaust system. Keep in mind that this type cam probably requires springs that exceed the stock Eddy's for maximum performance, and i would only use it with a upgrade to a good 1.5 ratio roller rocker. Also this is just one of many possibilities.

The other issue is that the entire combo will have to be somewhat coordinated, meaning rear gear ratio, tire diameter, and a decent torque converter.

I've just scratched the surface here.....Putting together a real nice total combination is definitely not as easy as it looks. :D



P.S. Now that we're getting the ball rolling, I know many other opinions will come about.....and that's a good thing.
Click to expand...

Not to high jack the thread here partner but I have a very similar
Build with the addition of some sealed pro flat tops. I running the mp .484 lift cam. Would going to a cam with more lift be a smart move? I'll be able to give the op more advice tomorrow when I start putting my motor together!
 
doogievlg said:
Not to high jack the thread here partner but I have a very similar
Build with the addition of some sealed pro flat tops. I running the mp .484 lift cam. Would going to a cam with more lift be a smart move? I'll be able to give the op more advice tomorrow when I start putting my motor together!
Click to expand...

doogie, the main reason I went that far on Matt's choice was because he stated that he wanted the "most" from a stock bottom end build. That and the fact that he is a little biased toward track use vs street.

I think your .484 is just fine for most builds in your range. You have a little more duration then the Howard's I picked, but with the SP pistons, you should end up with a little more compression and that should make up for the difference from his projected comp ratio with stock pistons. As far as the lift goes, I like as much as is "reasonably" possible for a low comp engine. But head flow still comes into play, like Eddy's vs stock 2.02 X's or J's. Plus you can possibly get away with a little less valvetrain cost (rocker/springs) then going real big on the cam.
 
check out Brodix B1 heads-great flowing heads out of the box.My LA 360 dyno at 422 HP,442 torq.Block set up as oldmanrick,has layed out.T&D 1.6 roller rockers,Comp roller cam.Edy RPM air gap,Holly street avenger 770 ,hooker comp headers,along with brodix B1-BA heads,9.95:1 comp.pump gas.
 
So your running running the sp pistons i take on that build dezert ? I just wanta be one if the few that can get into the 400+ on hp and tq with a stock bottom end build lol just seems like itll be a challange and i love them lol thanks rick im like the specs on that cam but whats your take on the b1 heads never realy looked into them ?
 
Thanks for all the suggestions keep them up ill be getting into the motor as soon as i get my hands on motor mount ): lol then will pit all this knowledge to use lol
 
ckdezert said:
check out Brodix B1 heads-great flowing heads out of the box.My LA 360 dyno at 422 HP,442 torq.Block set up as oldmanrick,has layed out.T&D 1.6 roller rockers,Comp roller cam.Edy RPM air gap,Holly street avenger 770 ,hooker comp headers,along with brodix B1-BA heads,9.95:1 comp.pump gas.
Click to expand...

I'll bet that's a fun ride :D.

I think we're somewhat on the same page. My hyd. choice was to give some good lift numbers under the curve with good flowing heads. I'm sure your roller certainly supplies that. Of all the "cast" engines built in the 60's/70's, the Mopar small block is the most reliable of any in my opinion. But I was still taking into account a reasonable rpm limit for his engine as far as durability. My thinking was to build the best power in the 4000 to 5700 rpm range, with a shift point at 6k. The fact that a 3.91 gear is a possibility makes me think I'm close with my cam thoughts.

ckdezert, what kind of rpm's are you turning yours? And what gear & torque converter do you run? Not questioning anything, just curious as to how thing are working for you so I can put it in the "vault"...lol. I love learning how different combo's work out...:thumbrig:
 
Bmatetic said:
rick im like the specs on that cam but whats your take on the b1 heads never realy looked into them ?
Click to expand...

I'm no cylinder head expert by any means, but I believe the Brodix heads are definitely a upgrade compared to the Eddy's. With that said, and hopefully understanding what you're trying to accomplish, i'd stay with the Edelbrock's at this point. I know you don't want to spend $$$ for bigger heads down the road, but even if you decide to build a stout short block later on, the Eddy's can be ported to make as much power as most would ever need shy of a full on race engine. I guess my thoughts on this are, the stock flowing RPM's are fine for now, and they have a lot of potential if/when you decide to move up down the road. While not cheap to get on the engine, I think they would be a good investment.
 
Ya i think you sold me on the eddie heads and that cam lol we shall see how they all perform in a couple weeks
 
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