Max RPM

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vntned said:
Lol! If you tried to run a '68 cuda up Deals Gap with a 360 turning 7k rpm you would be a legend. Any competent 360 in a light Abody with a stick shift should be a bear on that road. And like they said, that Z4s torque is half that of a hot 360 and doesn't even peak until 3k rpm! Build the 360 for 400hp, run any close ratio manual trans, and throw a 3.23-3.55 gear in the back. I promise you won't be worried about shifting past 6k rpm!

I've got a mild 360/4spd in my '64 dart, running a 3.55 gear. I've thrown lots of suspension at it. Sway bars, springs, torsion bars, fast ratio box, poly bushings, disc brakes, frame connectors, torque boxes, etc.. And I'd still bet I could get my stock GLH-T up the Tail of the Dragon faster, and not have to change underwear by the top!

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Aren't the GLH's something!

We have a Dakota shop truck that is starting to kick coolant out the exhaust and a '87 Daytona Shelby Z with some frame damage. My son now has a plan for the shop truck.

And then there is the sweet '88 Dodge station wagon and the '88 Daytona Pacifica with that body damage, humm.
 
Ooooo!!!!

I wanna come play in your sand box of parts!!!
 
what flyfish and IQ 52 said but loose the high compression for the street on pump gas and adjust the cam to match the heads and new rpm range
you willneed B3 mods if roller tip rockers
cubic inches are your friend and reduce the rpm needed to get the same HP/ torque
RPM is expensive and also a narrower power band
from there HP is in theheads
 
Wyrmrider said:
what flyfish and IQ 52 said but loose the high compression for the street on pump gas and adjust the cam to match the heads and new rpm range
you willneed B3 mods if roller tip rockers
cubic inches are your friend and reduce the rpm needed to get the same HP/ torque
RPM is expensive and also a narrower power band
from there HP is in theheads
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Bingo. This is my new fav way. I still love a high rpm screamer but as it was said above.......
 
Lots of info. Thanks guys.
As for the 6sp and not shifting much. I'm referring to when I go canyon carving. Similar to The Dragon. Drag racing is OK but I like to go around the corner better.
 
IQ52 said:
Ho, I have three Shelby Z's here, a Daytona Pacifica and no time.
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Used to drive those for demos... Loved the T-tops !
Remember driving GLHS Omnis and little Colt Turbos ... they would change lanes from torque steer before they made it accross the intersection! lol
Dakota 4x4 Convertibles ? Cruised the mtn roads of Id City in a brand new one ...that got a lot of looks !
 
LS-300 said:
Lots of info. Thanks guys.
As for the 6sp and not shifting much. I'm referring to when I go canyon carving. Similar to The Dragon. Drag racing is OK but I like to go around the corner better.
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I would recommend looking at posts and threads by @72bluNblu, @GMachineDartGT, @Mattax and a few others I can't remember off the top of my head, they're the A-body handling "experts" around here. If you haven't already, you'll definitely need to get your suspension and tires sorted out for that kind of driving before worrying about how high you can make a 360 redline.

I believe I drove on the Tail of the Dragon while I was on a work trip and if I can remember it correctly... your main concern will be keeping the rear drum brakes from locking up when you approach a downhill corner. Classic issue with old Mopars, the design of the rear drums makes them sensitive to locking up if the brake pedal is mashed quickly.
 
MopaR&D said:
I believe I drove on the Tail of the Dragon while I was on a work trip and if I can remember it correctly... your main concern will be keeping the rear drum brakes from locking up when you approach a downhill corner. Classic issue with old Mopars, the design of the rear drums makes them sensitive to locking up if the brake pedal is mashed quickly.
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Tell me about it. An unexpected panic stop locked the rears up and spun me into the ditch with my first Cuda in 1984. The current one has a propensity to do the same and a full retrofit, front and rear for bigger discs is on top of the list. As funds become available of course.
 
IQ52 said:
360 w/4.125 stroke on 91 octane
474 lb-ft @ 3,000 rpm
574 lb-ft (peak torque) @ 5,100 rpm
516 lb-ft @ 6,400 rpm
Run a 4.10 gear and leave it in 1:1 in the tranny. That'll pull a 54 mph corner and give you a 116 mph straight. If your tires will hook, the G forces will stretch your lips back to where your ears were and your ears will meet at the back of your head.
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Big IF on the tires hooking.

Would have to have a serious chassis to utilize that power on a public twisty road
 
Would you guys think a stroker with single plane would move the power band up some.

I’d think with the torque you’d need to shift less.
 
I have a 408 with 4" forged Scat crank, Scat rods, Icon pistons.
I shift at 6k RPM... maybe I'm being to conservative?
 
autoxcuda said:
Would you guys think a stroker with single plane would move the power band up some.

I’d think with the torque you’d need to shift less.
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It would move the HP peak higher. The low end torque would be weaker vs. a dual plane and depending on what other single plane you compare it to it would be dicey to say this one or that one is better because it would be only a few foot pounds difference but the dual plane would be a good 20+ pounds better. But still peak within a few pounds at the same (or really close) RPM.

A lot of this is cam / combo dependent. And very flexible. That’s why the answer is general. But I’d bet you’ll find it accurate.

mullinax95 said:
I have a 408 with 4" forged Scat crank, Scat rods, Icon pistons.
I shift at 6k RPM... maybe I'm being to conservative?
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Cam/combo dependent. If your cam is on or around a few degrees of let’s say 240@050, a fully well done set of ported head will have peak HP somewhere around 6500, give or take a 1 or 2 hundred rpm depending on the cam specs and how the lobe is ground.

An aggressive lobe will more than likely peak higher while the lazy lobe will peak lower. And then there’s the rest of the specs to speculate on. LOL!!!
 
Hellrats said:
I ran a 360 with a cast crank in a dirt track car for years at 7200 RPMs. Everyone else told me it would break too. I never did break a crankshaft. Hell I even ran stock rods. If it's correctly prepared and the oil system is up to stuff it will live. But for a street car I think it's over kill. Plenty of power up to 5500 or 6000 RPMs
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What mods were needed to run @ 7200 rpm? Please elaborate.
 
Rods were shot peened, crankshaft was internally balanced, KB pistons, fluid damper harmonic balancer, W5 cylinder heads, oil galleries in the block were opened up, lifter bores were sleeved, oil cross over tube added in the lifter gallery to feed the front main, 3 stage oil pump with a dry sump oil pan, two flat biscuit type oil filters (one fine, the other coarse), trap door oil pan. I think that was about it but I'm sure I missed something. Oh yea, and a very deep wallet.
 
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Ran it in this car. Can't find any pictures of the engine but I'll keep looking.

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rumblefish360 said:
Cam/combo dependent. If your cam is on or around a few degrees of let’s say 240@050, a fully well done set of ported head will have peak HP somewhere around 6500, give or take a 1 or 2 hundred rpm depending on the cam specs and how the lobe is ground.
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9.4 compression
Cam specs is 236/248@50 .571/.584 (blower cam)
IMM prepped EQ heads 2.02 intake valves 1.60 exhaust
No port work done to heads
Vortech V1 Ti-trim supercharger
Running 8-9 psi of boost
11.5 AFR at 6k rpm

Around 6k I don't feel the engine falling down. I just hold the throttle to the floor and the trans shifts at 6k. I don't manually shift it .... seems to shift better when the trans shifts on its own.
Mostly being conservative because I don't need to blow the engine...lol

rumblefish360 said:
aggressive lobe will more than likely peak higher while the lazy lobe will peak lower. And then there’s the rest of the specs to speculate on. LOL!!!
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Subtracting intake tappet lift at .050 from tappet lift at .006 I get 49.
285-236=49
From my understanding that is a fairly aggressive lobe... correct?
 
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IQ52 said:
Ho, I have three Shelby Z's here, a Daytona Pacifica and no time.
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No time? You are retired I thought! And your son was making antlers.?.

Do you enjoy staying busy? My dad is like that, He cannot sit still, and he is 73 going to church after waking up at 5 AM, driving a tractor for 6 hours in the Texas heat, doing something else for 2 hours and then driving back home for an hour and a half.-That's a Sunday. Week days for the past 40 years have been 4 AM and home around 8 PM. Tax payers truly got their money's worth from him. He is a terminator machine, not even human.

I thought I could catch up with the older generation, but they left me behind. Such self discipline, motivation, & determination. They could work circles and lap dozens of millennials and the rest of us.

What did the old man wizard say in 'Conan the Barbarian'? "Time to sleep in the grave."
 
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greymouser7 said:
No time? You are retired I thought! And your son was making antlers.?.

Do you enjoy staying busy? My dad is like that, He cannot sit still, and he is 73 going to church after waking up at 5 AM, driving a tractor for 6 hours in the Texas heat, doing something else for 2 hours and then driving back home for an hour and a half.-That's a Sunday. Week days for the past 40 years have been 4 AM and home around 8 PM. Tax payers truly got their money's worth from him. He is a terminator machine, not even human.

I thought I could catch up with the older generation, but they left me behind. Such self discipline, motivation, & determination. They could work circles and lap dozens of millennials and the rest of us.

What did the old man wizard say in 'Conan'? "Time to sleep in the grave."
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It's best to stay busy after retirement than sit on one's ***. Guy I knew worked hard while at work... but after retirement he didn't last long. Turned grey looking and past away. He had health problems but when he worked it wasn't to bad... but after he retried his health problems got worse...fast
 
I’d say yes you are shifting very early but I don’t know where your power curve ends. The hair drier super charger pushes the peak power point higher. And the more boost you are running, the higher it goes.

Sorry, the rest is really beyond my experience level.
The can’t tell you where leak power would be or when to shift for best results.
 
Subtracting intake tappet lift at .050 from tappet lift at .006 I get 49.
285-236=49

let's rephrase this if this is what you meant
subtracting duration at .050 tappet lift from duration at .006 tappet lift I get 49

never done it that way but interesting

Harvey Crane's "Intensity" was number of degrees between .004 to .050
Comp cams in their lobe catalog has "intensities" but measured at .006 lower number is quicker off the seat
you can also calculate open to .100 or .200 or from .050 yo .100 or 200 to see where it really gets going

btw stock 340 cam is longer seat to seat

get some governor weights for your TF and lighten I do not know which style you have- easy to do
 
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