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Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393743
02/28/13 02:21 PM
02/28/13 02:21 PM
Joined: Jan 2003
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Grand Haven, MI
patrick Offline
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I know you said you don't want the NV trans...mine held just fine with at least 400 ft lbs of torque at the crank...with street tires. I know a guy who's got his reg cab dakota into the 13s on slicks with a supercharged 318 and an NV3500.

if you keep your build mild, the 3500 will work ok.


or, you can source the Supra trans, those are much beefier than the NV3500, and some guys have put them behind their small blocks with the AX-15 bell housing.

but in general, yea, if you go with a TKO or a T-56, it's the same cost regardless of if you go small block or big block, the only part that's different between the 2 is the bell housing and possibly the flywheel depending on how your engine is balanced.




Dont get me wrong, after reading about the NV stuff i got all excited too... the gear spreads alone sold me... but again, not a simple bolt-in, and worse even than the Supra route. I'll hack my floors for a T-56 when the time comes (no time soon...), but not for a NV unit. Its not the power capacity... i doubt i'll exceed 400HP in any incarnation... this is a daily driver to have fun with, not a street incinerator. The NV sounds like a nightmare to fit and the shifter will be off as well.


SOOOO... unless i have the space and time to mess with the Supra install... i guess the OD stick is still gonna cost me dearly. Damn.




not necessarily....I'd really low buck it, forgo a gear and get an A833OD....with a mildish (say, under 226@.050) wide LSA cam (something in the 112 LSA) installed at 108, it should give you a wide enough powerband and flat torque curve to deal with the gear ratio spread (IIRC it's 3.09/1.74/1/.73)


1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393744
02/28/13 02:24 PM
02/28/13 02:24 PM
Joined: Jan 2003
Posts: 16,122
Grand Haven, MI
patrick Offline
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You also need to find an oil pan for the little engine. With all the stuff you have I would absolutely run the 383. If you were starting from scratch it would be different. The 383 even looks better.

Sheldon




Yeah... plus the mounts, linkage, distributor? manifold/headers, front accessories, and any other lil SB stuff i dont have. I definitely wont be going SB now... to get the thing running... Its more ov a down the road thing... to build a better more reliable commuter/canyon carver to live in this ridiculously expensive province.

Read: i want to drive my Challenger, but REALLY miss the injected 4.6L/5-speed in my old Mustang...




5.7 hemi...a non VVT take out (pre 09) with a small cam and tune using the OEM EFI should put out as much HP as a warm 360 or 383...at least here in MI, if you watch, you can find take outs with the harness and computer and under 60k miles for under $2k....


1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
Re: 360 Magnum vs 383... What would make more power? [Re: feets] #1393745
02/28/13 03:19 PM
02/28/13 03:19 PM
Joined: Apr 2005
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Kelowna, B.C. Canada
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Quote:

I NEVER look at lift at or above .500" if I'm not installing a cam over .600" lift.

Even with a .509" cam I'm not going to look at .500" flow. It's useless.
I want to see flow at .400" to .450" for usable info.

Can you tell me how long your cam stays open above .500" lift?




True enough; all that data is in the links I posted too.


Dave


1970 Super Bee 440 Six Pack 1974 'Cuda 2008 Ram 3500 Diesel 2006 Ram 3500 Diesel 2004.5 Ram 2500 Diesel 2003 Ram 3500 Diesel 2006 Durango Limited [url] http://1970superbee.piczo.com [/url]
Re: 360 Magnum vs 383... What would make more power? [Re: patrick] #1393746
02/28/13 03:28 PM
02/28/13 03:28 PM
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Manitoba, Canada
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You also need to find an oil pan for the little engine. With all the stuff you have I would absolutely run the 383. If you were starting from scratch it would be different. The 383 even looks better.

Sheldon




Yeah... plus the mounts, linkage, distributor? manifold/headers, front accessories, and any other lil SB stuff i dont have. I definitely wont be going SB now... to get the thing running... Its more ov a down the road thing... to build a better more reliable commuter/canyon carver to live in this ridiculously expensive province.

Read: i want to drive my Challenger, but REALLY miss the injected 4.6L/5-speed in my old Mustang...




5.7 hemi...a non VVT take out (pre 09) with a small cam and tune using the OEM EFI should put out as much HP as a warm 360 or 383...at least here in MI, if you watch, you can find take outs with the harness and computer and under 60k miles for under $2k....




I don't think the OP has 2k in his budget, not the mention the extra 2k in addons it'll take to get that engine in the car.

Re: 360 Magnum vs 383... What would make more power? [Re: 70Cuda383] #1393747
02/28/13 03:30 PM
02/28/13 03:30 PM
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Kelowna, B.C. Canada
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Quote:

I dunno, but I think port size, velocity, etc. is all moot. CFM is CFM. it's a measure of volume per time. the more volume per time you move, the more power you can make, regardless of whether it's a super high speed velocity port with small cross sectional area, or a big fat wide port with very slow speed.

(obviously, as long as speed is fast enough to not cause the fuel vapor to fall out of suspension, and not so fast that you go turbulent)




Airflow is a specialty of mine, though my area of expertise is around exhaust/extraction systems the math is the same. Assuming that any testing is done at the same static pressure, then CFM is indeed CFM. Of course (given the same configuration), the smaller the port, the more velocity and therefore an increase in static pressure is inevitable...so if the pressure is constant, this translates to lower volumes.

...at the end of the day, the head that moves the most air has the potential to make the most power. Obviously there are other considerations like combustion chamber shape, etc. but all other things being equal, this is the case.

Dave


1970 Super Bee 440 Six Pack 1974 'Cuda 2008 Ram 3500 Diesel 2006 Ram 3500 Diesel 2004.5 Ram 2500 Diesel 2003 Ram 3500 Diesel 2006 Durango Limited [url] http://1970superbee.piczo.com [/url]
Re: 360 Magnum vs 383... What would make more power? [Re: DaytonaTurbo] #1393748
02/28/13 09:58 PM
02/28/13 09:58 PM
Joined: Jan 2005
Posts: 4,862
the frozen wastes...
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You also need to find an oil pan for the little engine. With all the stuff you have I would absolutely run the 383. If you were starting from scratch it would be different. The 383 even looks better.

Sheldon




Yeah... plus the mounts, linkage, distributor? manifold/headers, front accessories, and any other lil SB stuff i dont have. I definitely wont be going SB now... to get the thing running... Its more ov a down the road thing... to build a better more reliable commuter/canyon carver to live in this ridiculously expensive province.

Read: i want to drive my Challenger, but REALLY miss the injected 4.6L/5-speed in my old Mustang...




5.7 hemi...a non VVT take out (pre 09) with a small cam and tune using the OEM EFI should put out as much HP as a warm 360 or 383...at least here in MI, if you watch, you can find take outs with the harness and computer and under 60k miles for under $2k....




I don't think the OP has 2k in his budget, not the mention the extra 2k in addons it'll take to get that engine in the car.




Yep... would be nice, but hardly an easy swap for a well-equipped shop, let alone my Mad Max mess...

Re: 360 Magnum vs 383... What would make more power? [Re: patrick] #1393749
02/28/13 10:03 PM
02/28/13 10:03 PM
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I know you said you don't want the NV trans...mine held just fine with at least 400 ft lbs of torque at the crank...with street tires. I know a guy who's got his reg cab dakota into the 13s on slicks with a supercharged 318 and an NV3500.

if you keep your build mild, the 3500 will work ok.


or, you can source the Supra trans, those are much beefier than the NV3500, and some guys have put them behind their small blocks with the AX-15 bell housing.

but in general, yea, if you go with a TKO or a T-56, it's the same cost regardless of if you go small block or big block, the only part that's different between the 2 is the bell housing and possibly the flywheel depending on how your engine is balanced.




Dont get me wrong, after reading about the NV stuff i got all excited too... the gear spreads alone sold me... but again, not a simple bolt-in, and worse even than the Supra route. I'll hack my floors for a T-56 when the time comes (no time soon...), but not for a NV unit. Its not the power capacity... i doubt i'll exceed 400HP in any incarnation... this is a daily driver to have fun with, not a street incinerator. The NV sounds like a nightmare to fit and the shifter will be off as well.


SOOOO... unless i have the space and time to mess with the Supra install... i guess the OD stick is still gonna cost me dearly. Damn.




not necessarily....I'd really low buck it, forgo a gear and get an A833OD....with a mildish (say, under [Email]226@.050)[/Email] wide LSA cam (something in the 112 LSA) installed at 108, it should give you a wide enough powerband and flat torque curve to deal with the gear ratio spread (IIRC it's 3.09/1.74/1/.73)




Yeah... theres that option, but i just sold my 833OD a couple years ago and having been in a pretty hot car (340 Demon) with that tranny i gotta say i just really didn't like that gear spread. For sheer low-buck i'm more inclined to go with my 1:1 833 and 2.76 rear gears. Better spread, horrible off the line, but then again i'm not drag racing.

Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393750
02/28/13 10:09 PM
02/28/13 10:09 PM
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As for the airflow question... ultimate potential is not a concern for me. I'm building this car for daily driving, long distance (possibly very long distance) trips, reliability and just fun. I sold all my 600HP 400 lowdeck stuff and really... i would have no use for such a thing. I'm building a car i can drive and play with ALL the time... not something i take out only on sunny summer weekends with a support vehicle. 350-400HP would be more than fine in this 3100-3200lb car, and down the road squeezing another 50-75HP from the combo shouldn't be a big deal. It'd be nice to have 500+HP, but then i'm using a lot more gas...

The 450HP 360 Magnum build in that link with the Edelbrock heads was intriguing... That'd be perfect... or maybe even a similar combo on the 318 Magnum...

Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393751
02/28/13 10:45 PM
02/28/13 10:45 PM
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st.cloud fl
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what you described go with 360 mag follow 380hp crate engine combo.modern serpentine belt acc.modern ,every part store in america kind of thing.

Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393752
02/28/13 11:01 PM
02/28/13 11:01 PM
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Posts: 3,300
Northern Indiana
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To me it really depends on what your definition of power is?
Torque to get you moving,or power up top during a high rpm blast?
I see people comment that they would rather have a 383 to get the torque of a big block,but the 360 has a longer stroke than a 383. The 360 having a longer stroke and smaller port cross section will make more torque similarly equipped
Where a 383 shines,in my opinion,is its short stroke,big bore,and decent cross section for the cubic inches. They like to turn some rpm to make some power upstairs . Those 516 heads are not a bad piece either,closed chambers for decent quench.
I also think one of the advantages of the Magnum heads is the flow they get with the smaller valves than a similar flowing LA style head. This keeps the valve further away from the cylinder wall and helps keep from shrouding the valve as much with the small bores.
Keith

Re: 360 Magnum vs 383... What would make more power? [Re: Dunnuck Racing] #1393753
02/28/13 11:47 PM
02/28/13 11:47 PM
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maryland
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really, for a cheap build, i still think... grab a running 383

have the heads trimmed a bit at a machine shop, say .010 - .020 or so. nice and flat, probably drop the cc's by 3 or 4. put new valve seals on while you are in there, that way they can check the springs, make sure none of them are flat. a good new head gasket. if budget allows, a .500 or so cam. fresh up the carb. let her rip.

if you have a friendly relationship with the machine shop for the head cleanup you are golden.

i dont think you can go to a solid cam that will cost you because of the rockers. but it doesnt sound like you need solids, you will probably be under 6k rpm most of the time.

Re: 360 Magnum vs 383... What would make more power? [Re: DPelletier] #1393754
03/01/13 02:07 AM
03/01/13 02:07 AM
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Kalispell Mt.
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I read that article and can not find what bore the BB heads were tested on but I bet it was the bigger 440 bore so on a 383 they will probably flow less wit the smaller bore and since they are almost tied with the magnum on the intake already they will probably flow less on a 383 than a magnum will on a 360 plus you lose the efficiency and no leak sealing of the magnum design. Also the 300 hp crate motor might make 320+ hp but remember the M1 single plane can not hold the jock strap of an RPM air gap AND the truck cam is actually bigger and better than a 300hp crate cam. I bet if you gave both of them the RPM intake and a set of headers the 5.9 magnum would make for a faster car with a broader TQ curve with less leaks and more MPG and weighing significantly less without buying expensive aluminum stuff.


I am not causing global warming, I am just trying to hold off a impending Ice Age!



Re: 360 Magnum vs 383... What would make more power? [Re: d-150] #1393755
03/01/13 06:50 AM
03/01/13 06:50 AM
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the frozen wastes...
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what you described go with 360 mag follow 380hp crate engine combo.modern serpentine belt acc.modern ,every part store in america kind of thing.




That last bit i really like. In my obsession with modern efficiency i had dreamed up all kinds ov wonderful swaps for this car... but then i'd be driving my old 96 GT again, and thinking... yeah its great when everything is working, but when ANYTHING goes wrong... i'm hooped. As it stands, my girlfriend's (my old) 96 GT sits in her carport now, needing an engine... and for that she's looking at minimum $2500. I built my 72 440 Charger with an assortment ov non-power tools that literally fit in a large picnic cooler... I love the new HP tech, but i love simple too.

Re: 360 Magnum vs 383... What would make more power? [Re: Dunnuck Racing] #1393756
03/01/13 06:58 AM
03/01/13 06:58 AM
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Quote:

To me it really depends on what your definition of power is?
Torque to get you moving,or power up top during a high rpm blast?
I see people comment that they would rather have a 383 to get the torque of a big block,but the 360 has a longer stroke than a 383. The 360 having a longer stroke and smaller port cross section will make more torque similarly equipped
Where a 383 shines,in my opinion,is its short stroke,big bore,and decent cross section for the cubic inches. They like to turn some rpm to make some power upstairs . Those 516 heads are not a bad piece either,closed chambers for decent quench.
I also think one of the advantages of the Magnum heads is the flow they get with the smaller valves than a similar flowing LA style head. This keeps the valve further away from the cylinder wall and helps keep from shrouding the valve as much with the small bores.
Keith




Exactly my thinking when starting this thread. Now, add to this the Magnums roller technology over the 383's flat-tappet hydraulic, and the better shaped chambers... And then there is the rather huge difference in reciprocating weights, and as mentioned before, the apparently much better chance ov finding a nicely sealed and much newer engine in general (than my nice but 45 year old 383).

I actually really like RPM's (i WAS gonna build a stock-stroke 400 with ported B1BS heads and a tunnel ram for this car...), and my car is light with a stick... but right now what i want and what i need are probably two different things. I'll still do the 383 right now... i have to, its all there and ready to go, but i think i will be planning to go small block at the first opportunity.

Re: 360 Magnum vs 383... What would make more power? [Re: 74yellowduster] #1393757
03/01/13 07:05 AM
03/01/13 07:05 AM
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the frozen wastes...
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really, for a cheap build, i still think... grab a running 383

have the heads trimmed a bit at a machine shop, say .010 - .020 or so. nice and flat, probably drop the cc's by 3 or 4. put new valve seals on while you are in there, that way they can check the springs, make sure none of them are flat. a good new head gasket. if budget allows, a .500 or so cam. fresh up the carb. let her rip.

if you have a friendly relationship with the machine shop for the head cleanup you are golden.

i dont think you can go to a solid cam that will cost you because of the rockers. but it doesnt sound like you need solids, you will probably be under 6k rpm most of the time.




The plan is to just dump it in as-is, but with a new Whiplash cam (229/242, .518", 107 lobe sep), new springs, etc. Then port up my other 516's, have 'em chopped as much as i dare (.060"?), install some 1.81" exhaust valves, chop the guides a bit too, all new stuff, then swap 'em on later. That, with my SD intake, 800 carb, headers, MSD ignition, blah blah... should make that lil car scream...

Re: 360 Magnum vs 383... What would make more power? [Re: HotRodDave] #1393758
03/01/13 07:10 AM
03/01/13 07:10 AM
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I read that article and can not find what bore the BB heads were tested on but I bet it was the bigger 440 bore so on a 383 they will probably flow less wit the smaller bore and since they are almost tied with the magnum on the intake already they will probably flow less on a 383 than a magnum will on a 360 plus you lose the efficiency and no leak sealing of the magnum design. Also the 300 hp crate motor might make 320+ hp but remember the M1 single plane can not hold the jock strap of an RPM air gap AND the truck cam is actually bigger and better than a 300hp crate cam. I bet if you gave both of them the RPM intake and a set of headers the 5.9 magnum would make for a faster car with a broader TQ curve with less leaks and more MPG and weighing significantly less without buying expensive aluminum stuff.




I'm sold i'm sold already! Haha... now yer just getting me excited...

The 300HP crate has a smaller cam than the junkyard 360 does...??? Again, the only really crappy deal is that real UNDER-chassis SB headers cost more than real estate.

Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393759
03/01/13 11:09 AM
03/01/13 11:09 AM
Joined: Jan 2003
Posts: 74,907
U.S.S.A.
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Quote:

Quote:

really, for a cheap build, i still think... grab a running 383

have the heads trimmed a bit at a machine shop, say .010 - .020 or so. nice and flat, probably drop the cc's by 3 or 4. put new valve seals on while you are in there, that way they can check the springs, make sure none of them are flat. a good new head gasket. if budget allows, a .500 or so cam. fresh up the carb. let her rip.

if you have a friendly relationship with the machine shop for the head cleanup you are golden.

i dont think you can go to a solid cam that will cost you because of the rockers. but it doesnt sound like you need solids, you will probably be under 6k rpm most of the time.




The plan is to just dump it in as-is, but with a new Whiplash cam (229/242, .518", 107 lobe sep), new springs, etc. Then port up my other 516's, have 'em chopped as much as i dare (.060"?), install some 1.81" exhaust valves, chop the guides a bit too, all new stuff, then swap 'em on later. That, with my SD intake, 800 carb, headers, MSD ignition, blah blah... should make that lil car scream...




check those 516 for core shift , they have small exh ports to begin with so going to that big an exh valve and it's require port work to make it useful might get a little scarey ???

Re: 360 Magnum vs 383... What would make more power? [Re: JohnRR] #1393760
03/02/13 07:46 AM
03/02/13 07:46 AM
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Quote:

Quote:

Quote:

really, for a cheap build, i still think... grab a running 383

have the heads trimmed a bit at a machine shop, say .010 - .020 or so. nice and flat, probably drop the cc's by 3 or 4. put new valve seals on while you are in there, that way they can check the springs, make sure none of them are flat. a good new head gasket. if budget allows, a .500 or so cam. fresh up the carb. let her rip.

if you have a friendly relationship with the machine shop for the head cleanup you are golden.

i dont think you can go to a solid cam that will cost you because of the rockers. but it doesnt sound like you need solids, you will probably be under 6k rpm most of the time.




The plan is to just dump it in as-is, but with a new Whiplash cam (229/242, .518", 107 lobe sep), new springs, etc. Then port up my other 516's, have 'em chopped as much as i dare (.060"?), install some 1.81" exhaust valves, chop the guides a bit too, all new stuff, then swap 'em on later. That, with my SD intake, 800 carb, headers, MSD ignition, blah blah... should make that lil car scream...




check those 516 for core shift , they have small exh ports to begin with so going to that big an exh valve and it's require port work to make it useful might get a little scarey ???




I've done my homework (here), and i'm pretty convinced i'll be okay with the 1.81" valves, and the throat job/porting to make 'em happy. What does worry me about these heads is just the actual porting... I've got a good idea ov how far i can go and whats good in a typical 915/906/452/etc head, but these are supposedly thinner and more porous. I had no desire to hog out these heads, but i was going to do the usual stuff to them.... and not quite sure what i can get away with.

I suppose i could just sell that box ov new Ferreas and throw some old 1.74's in there, but then i'm still paying to have them back-cut. I bought those 1.81"s specifically for these heads.

Re: 360 Magnum vs 383... What would make more power? [Re: Pale_Roader] #1393761
03/02/13 05:16 PM
03/02/13 05:16 PM
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Holly/MI
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Interesting thread topic................the 360 has a longer stroke and shorter rod.............383 has longer rod, shorter stroke. Lets overlook the 23 more cubes to the 383 for moment...........

typically that 383 will get you better efficiency/mpg at a slightly higher rpm. The 360 will give you more torque off idle/low rpm with the longer stroke and more agressive rod/stroke ratio...............

where is this going???? With the 2.94 gearing and LOTS of mileage..........I'd be looking to do the 360 UNLESS it's all interstate travel.

I, personally, wouldn't want to feed a thirsty V8 on a high mileage daily basis. If I had to, I'd build it for max mpg and big torque down low where it's going to spend all of its time.

I put LOTS of hours into porting a set of 516's for a .060 over 383 in my 69 RR. Did the MP porting templates. Went 1.74 exhaust valve too. Just gasket matching, opening up the bowls, working the valve guide boss can all run into lots of hours. And I think with a mild cam it would raise the efficiency of the motor such that it isn't a detriment to mpg. My RR got 14 mpg hwy to Indy from MI with a 750 AFB, single-plane, 484MP cam and 3.91 gears. Not a gasmizer deal at all but it did like to run at 3000-3400. I gained 2-3 mph thru the traps too!


R.I.P.- Gary "Coop" Davis 02/09/68-05/13/04
Re: 360 Magnum vs 383... What would make more power? [Re: Dean_Kuzluzski] #1393762
03/02/13 06:56 PM
03/02/13 06:56 PM
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Desert Tracker
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Quote:

Interesting thread topic................the 360 has a longer stroke and shorter rod.............383 has longer rod, shorter stroke. Lets overlook the 23 more cubes to the 383 for moment...........

typically that 383 will get you better efficiency/mpg at a slightly higher rpm. The 360 will give you more torque off idle/low rpm with the longer stroke and more agressive rod/stroke ratio...............

where is this going???? With the 2.94 gearing and LOTS of mileage..........I'd be looking to do the 360 UNLESS it's all interstate travel.

I, personally, wouldn't want to feed a thirsty V8 on a high mileage daily basis. If I had to, I'd build it for max mpg and big torque down low where it's going to spend all of its time.

I put LOTS of hours into porting a set of 516's for a .060 over 383 in my 69 RR. Did the MP porting templates. Went 1.74 exhaust valve too. Just gasket matching, opening up the bowls, working the valve guide boss can all run into lots of hours. And I think with a mild cam it would raise the efficiency of the motor such that it isn't a detriment to mpg. My RR got 14 mpg hwy to Indy from MI with a 750 AFB, single-plane, 484MP cam and 3.91 gears. Not a gasmizer deal at all but it did like to run at 3000-3400. I gained 2-3 mph thru the traps too!




A 383 can be built to be efficient as can a 360. the question is simple how hard are you willing to spin the motor at cruising speed. Since it take extra fuel to keep a short stroke motor accelerating (under load) vs a longer stroke motor, it would be much more feasible to build a motor with more low end torque in it. Since you do have 95% percent of the parts for the 383, build it. The Whiplash cam WILL raise the cylinder pressure (increase static-EFFECTIVE compression) by allowing cam timing events to happen sooner in the combustion process. The two
things you must do to "maximize" your power/efficiency/mileage goals is to degree the cam CAREFULLY!! Cam timing is critical and I'd make sure the damper is indexed properly for ignition timing/tuning purposes. Old dampers could have their ignition mark OFF by several degrees! All the above mods/checks can net you a
smoother, more efficient motor. The K.I.S.S. (Keep It Simple Stupid) principle always works!



"Stupidity is Ignorance on Steroids"
"Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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