Dyno'ed My 360..it's a pig..what next?

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Cheap fix... You have enough carb to run well into the 13"s. Your carb needs more pressure, 7lbs. 4 corner jetting is not for a street car, it is for WOT only. 1 5/8 header are fine.
Check your compression on the engine, check on each cylinder. If they are low pull a head and check your piston and valve clearance. Shaving the head or using a thinner head gasket can raise your compression, with low cost, Possibly need a shorter pushrod to do this, depends on how much you cut. Take out the valves
and "clean up" those ports. These are all basic parts with out to much investment.
You have enough carb to do what you want there, it just need tuned in.
 
750 would be too big for the street but for the dyno it might work. If you want to replace the carb and keep it on there for street driving use a 650 VS holley at least those don't take an hour just to do one jet change.

You don't need to drop $10k on a new engine, take it one step at a time... figure out the leaning issue, then try a slightly bigger carb.

After that i would just swap the heads and cam together; nothing crazy just something like Mike from MRL said, decent inexpensive iron heads but with 1.88/1.60 valves and a good valve job and put in a modern cam not that old lazy Chevy grind copycat. You will pick up power and torque everywhere and probably some MPG too, all for less than $3k... probably less than $2k if you do all the assembly yourself.

That 727-based trans will suck noticeably more power than a 904-based one FYI but you have what you have and like you said the overdrive is a great feature to have in a cruiser.
 
And for the record my 360 makes 330 HP at the crank verified by trap speed at a drag strip running an AFB. It can work you just gotta fiddle with it more whereas dropping on a good holley 650 will be way quicker and easier.

I actually leaned out my AFB for street use and i have a 750 Mighty Demon set up for the track.
 
A 750 vacuum secondary is not to big for the street. most of the time it will be on 2bbls and be pretty snappy. it needs more air flow, heads are where to start. stock valves don't flow for crap. good valves and good valve job, some minor bolw work will make a Huge difference.
 
MRL Performance said:
A 750 vacuum secondary is not to big for the street. most of the time it will be on 2bbls and be pretty snappy. it needs more air flow, heads are where to start. stock valves don't flow for crap. good valves and good valve job, some minor bolw work will make a Huge difference.
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It'll work if you know how to set it up right but would there really be much noticeable power gain over a 650 on a mild engine like that? And how much flow gain just from 1.88 to 2.02 intakes if they both have good seat and bowl work? Just curious as you're obviously a highly experienced pro at this i love reading about your builds.
 
It sounds like you were happy with the performance until you strapped it to a dyno and didn't see the numbers you "thought" you would see. If you want higher numbers, first of all get the tune right, then take it to a different dyno.....BOOM now your happy.
 
MRL Performance said:
A 750 vacuum secondary is not to big for the street. most of the time it will be on 2bbls and be pretty snappy. it needs more air flow, heads are where to start. stock valves don't flow for crap. good valves and good valve job, some minor bolw work will make a Huge difference.
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the 1.88 valve heads do flow very well. they have more port velocity over 2.02 valve. in stockers, the 1.88 340's are just as fast as a 2.02 340 motor. 2.02 is not the answer always. stainless 1.88 nail head valves do help flow!!!
 
replicaracer43 said:
It sounds like you were happy with the performance until you strapped it to a dyno and didn't see the numbers you "thought" you would see. If you want higher numbers, first of all get the tune right, then take it to a different dyno.....BOOM now your happy.
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This^^

And/or start with getting the Dcr up in the 8 to 8.5 range.Until the cylinder pressure comes up out of the basement, IMHO, you're always gonna be "bugged"
That 518 has a bit wider ratios, so you kinda need to keep the cam conservative, to keep the powerband also wide, which is what your current cam is doing.
As for me I'd push the detonation limit at 8.5 Dcr, and if I had to, I'd retard the cam, to find the intake closing angle that satisfies the octane requirement, and then order a cam to satisfy that.
If you really need a bigger HP number, find it in the heads..
But really, a street cruiser needs to be torque biased, which is exactly what you have.
I built my first street iteration like that , and it might just have been my favorite streeter.

Also, if you're driving style keeps you below 5000 rpm, there's really no point in chasing HP numbers, cause to get them, you may have to give up a bit of the low rpm torque. And your curve has a nice peak, right where a streete cruiser needs it.
 
I agree, like I said, stock valves don't flow well compared to good HP aftermarket valves. Problem is there don't seem to be any good 1.88 intakes anymore. Might as well go with a bigger intake. 2.02 may not always be the answer. Stock Magnums are 1.92, and I have had great luck in the past with the Chevy 1.94 intakes as well.

I did a test years ago with a stock 360. Just a mild build, ran it with the stock valves and a stock type valve job. Took the heads off, popped in some 2.02's w/HP valve job, and MILD bowl blend. Changed nothing else, picked up HP and TQ all thru the rpm band. Peak to peak was around 20 hp/tq, but in some areas under the curve it was 30+.
 
Its got tuning shortfalls and already someone is suggesting it needs big valves and a 5 angle valve job. SMH
 
superdart said:
To answer some questions (I'll try to get them all):

Pistons - I don't know. They came with the lower rotating assm when I bought the car (some assembly required). In fact, all of the lower assembly, heads, etc, came with the car when I got it (I added the roller rockers and chrome shafts later). Things like the cam, intake, carb, peripherals, etc I bought to get the engine together. Yes, it's an issue, and it's one reason I'm leaning toward hitting the reset button and starting over, so I KNOW what is in the car....but that is more money that dealing with what I have.

Fuel - What I meant was I don't think I'm going to get near the 240 everyone was expecting just through fixing the A/F issue. Fuel volume and pressure and good.

Money - My card has a high limit....but I don't like running my hobbies on credit. :D Honestly, dropping $10k on a motor, for my purposes, is silly. If I was going to spend that I'd sell the Dart, the Avenger, add that money, and put it down on a 392 Scat Pack, or even "just" a Super Track Pack R/T.

Street Cruiser - They hit 5200 on the dyno...that is probably the FASTEST that motor has ever spun in 15 years. Even in it's current state it "works" as a cruiser and fun car just fine. The fact that it's "not right" will just bug me to no end.

Yes, I know the 518 OD saps power, but turning 2200 rpms at 70mph is just NICE. I figured this was going to hurt some.

Tuning - maybe 5-7k miles on the cap, plugs and wires. Trans and fuel filters get changed every few years. Fuel tank, sending unit, etc are all relatively new.

After looking at what stock 4bbl 360s were back then (220/280), versus mine (with the lean fuel condition) the numbers are probably about right. There was definitely a torque increase, even with the 518 and the lean A/F. We'll see what happens after some carb work and general tuning.

If I know it's a least "right" maybe I'll be happy. I considered a nice little 318 instead, but then I'm giving up the low end torque that's handy for daily driving.
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Agree with your philosophy.... The dyno is nice.how does it feel on the street TO YOU. As for dyno numbers,drag strip trap speed is the most honest,IMO.
 
There might be shortfalls in your build, mismatched components, etc. But really start at the beginning. Get the engine tuned and running the best it can, pull every last hp out of it. Once it's running its best, then you can really narrow in on where its shortcomings are. And tweak for what you want out of it.

Or if you're after a number. Figure out what that number is. Then do what others have said. Pull it apart this winter and build for that number. Rather than throwing part after part at it, hoping to hit some goal of performance that you haven't set for yourself yet.
 
Were you happy with how it ran before you saw some crappy dyno numbers? If so, screw the dyno.
 
I'd start over with a used 96-2000 5.9 magnum motor- 240hp rated stock..

5.9 magnum long block
Serp belt under drive pulley
Carb intake
Mopar roller cam/springs for cam
Good headers
Summit 2.5" X pipe
Your choice mufflers
Tail pipes or dumps
Non stock stall converter for the A518 - this will help HEEPS
4.10 gears - you'd be around 2,750- 2,900rpm cruising at 70mph - don't need a high gear with the OD.. I had 4.30's in my old 5 speed Mustang - cruised 75mph @ 3,000rpm
 
RustyRatRod said:
Were you happy with how it ran before you saw some crappy dyno numbers? If so, screw the dyno.
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Agree tune the carb a bit and take it to a drag strip. Dynos are good for seeing effects of tuning/parts changes but absolute numbers don't mean much. OP did say it didn't feel quite as strong as it should.
 
Throw a 200 shot on it and beat it until it breaks. :)

In all seriousness if your chasing dyno numbers then you will never be satisfied and your bank account will go down the drain in no time.
 
Just another option for the OP to consider, why not take it back to the shop with the Dyno and pay them to tune it on the dyno before you go out and buy a bunch of new parts? It seems the OP was happy until he saw numbers that didn't meet expectations.
If you're happy with your car just drive it and enjoy it and don't get caught up in the numbers game.
 
Uh,I see you have an overdrive trans.
Put 4.11 r&p and roast tires and mustangs.
Tune by seat of pants for new ring gear as that's what matters.
 
replicaracer43 said:
Its got tuning shortfalls and already someone is suggesting it needs big valves and a 5 angle valve job. SMH
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Problem is the tuning shortfalls aren't all that is wrong with it. :)

My cars run just fine. My VW makes more power than his 360.

Just sayin.

Brian
 
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