Max RPM

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LS-300

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I'm looking at building a small block, 360, to run on the street. Is it possible to build one that can safely have a 7-8k redline? It also will need to be between 350 & 450 whp.
 
Sure. Good oiling, good parts. No sweat.
But no since spending all those dollars on those parts to make that tiny amount of power.
You can make more power than you are wanting with cheap parts and staying at or under 6,000 rpm.
Rpm cost dollars. Stay away from it if you can( rpm)
 
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
 
^^^^^^^^ What he said is spot on ^^^^^^^^^
Ditto!

At 450 RWHP, your ceiling, this translates to a 500+ hp engine. You can do this under 6700 RPMs.
750, rpm, trick flow heads, zero decked slugs.
RAMM dyno’d a 360 to 541 HP @ 6700, though he used a Super Victor, IMO, you would still make over 500 with the rpm intake. This is the cam he used and it would deliver. I would suggest 1.6 rockers since it would help lift the valve a bit more and take advantage of the cylinder head better.

20-248-4 - Magnum™ Mechanical Flat Tappet Camshafts
 
I have been doing a bit of back country road "driving" and like a car that has a wide RPM & power band. Getting out of a tight turn and heading to the next I don't want to have to change gears very often. I plan on a 5 or 6 sp manual as well. I have a Z4 and have a ball "Canyon carving" in it. I would like to do this in my 68 Barracuda as well. That is why I wonder about having a higher RPM capability.
 
I have been doing a bit of back country road "driving" and like a car that has a wide RPM & power band. Getting out of a tight turn and heading to the next I don't want to have to change gears very often. I plan on a 5 or 6 sp manual as well. I have a Z4 and have a ball "Canyon carving" in it. I would like to do this in my 68 Barracuda as well. That is why I wonder about having a higher RPM capability.


Better have a damn good oil pan. And you need to fully understand how these engines oil and why they don't oil. The latter is the most important to learn.

There are several threads on here that cover it.

Just my .02 and it's worth what your paying for it. 7 is fairly easy. You want 8 and want to make power there, you better have your **** wired tight.
 
Is this OK with your concerns?
(Courtesy of @RAMM )

9C1858EE-7AFA-465A-82FF-A0044A42DE03.jpeg
 
Basically you are trying to push the power band up, The route I would take is to make it fatter on both ends, with 6k being the ceiling.
The driving characteristics you are after are a culmination of the entire driveline, revving to the moon is a less than perfect way to get you there
 
I found when I was driving the tail of the dragon I would keep the rpm between 3k & 6200 using a RL at 7000. This would allow me to get off the corner with speed and if I had to shift before the next tight turn so be it. I don't have to have 400 RWHP but at least 300 would be fun. Oil pan mods to stop the slosh is important as I don't want it to starve.
 
I found when I was driving the tail of the dragon I would keep the rpm between 3k & 6200 using a RL at 7000. This would allow me to get off the corner with speed and if I had to shift before the next tight turn so be it. I don't have to have 400 RWHP but at least 300 would be fun. Oil pan mods to stop the slosh is important as I don't want it to starve.

Your BMW Z4 makes half the torque of a built Mopar 360 but the weight is not much different. If it's geared right your Barracuda won't need to rev past 6000 RPM; on that same section of road you could keep it between 2500 and 5000 RPM and it would accelerate off the turns and have enough "legs" to get you to the next turn without needing to shift. Regardless of the setup you'll be shifting a lot less because of that massive Mopar torque.

It's all about knowing where your engine makes torque and how to gear it properly. If you're running out of revs on a straightaway with a 400 HP engine it's time to put in some taller gears.

A long time ago I asked the same question, "how can I build a 360 that revs to 7k RPM?" After I built my first 360 and felt how insane the torque from an engine like that in a 3200-lb Duster was I realized the only reason to push these engines that high is if you need more power. Power is a function of torque and RPM, nothing more. Most decent 360s make at least 400 lb-ft through most of the RPM range so at the "crossover" point of 5252 RPM you're making 400 HP. You can't spin it faster and NOT make more power, unless there's something messed up with your combo.
 
Why screw around. Just snag one of the Nascar Dodge R5 truck engines off of ebay. 8000+ rpm all day and double your hp/tq needs.
 
I have been doing a bit of back country road "driving" and like a car that has a wide RPM & power band. Getting out of a tight turn and heading to the next I don't want to have to change gears very often. I plan on a 5 or 6 sp manual as well. I have a Z4 and have a ball "Canyon carving" in it. I would like to do this in my 68 Barracuda as well. That is why I wonder about having a higher RPM capability.
You have made me laugh, thank you. You plan on a 6 speed manual and not shift very much.
 
I'm looking at building a small block, 360, to run on the street. Is it possible to build one that can safely have a 7-8k redline? It also will need to be between 350 & 450 whp.

Easy peasy...here you go....although this over shoots your horse power goal by a good chunk.

· 360 block, 4” Scat forged crank, Scat I-beams, Icon forged flat top pistons

· Ported Edelbrocks, 57cc, Hughes solid 264/268 @ 0.050, Howards oil through lifters, Comp Pro Mag rockers, PAC springs

· 13:1 compression, “750” e85 carb built by me (you should use a 950), Victor intake

This is what I built for my Barracuda....do that with a 3.58 crank and you've got a motor that should pull hard to 7500. You can wind the 4" motors up, but it puts a lot of load on the rods...that's why I shift mine at 6500, even though it pulls REALLY hard to my rev limiter @7000.

You will need to keep the valve train & rotating assembly light for it to live.
.....and seriously....not wanting to shift much....with a 5-6 speed.........:realcrazy:
 
I see a lot guys over rev their engine. They have no idea where it makes power and shift at ridiculous RPM's or "hold my foot in it until it stops making power" then shift. If you are going to take your car to 7500, make sure it makes power there, and regardless of everything else, gear the car properly.
 
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!

IMG_20190518_143028.jpg
 
Nope can't be done... Sorry..

**** !! Someone forgot to tell the 360 W2 Solid roller motor in my 73 Dart Sport that ! It would hit high 7000s in a heartbeat .

But still... why ? If all you need is 450 hp for the street just go 408 and run deeper gears.
 
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.
 
IDK why that wouldn't be about perfect for the OP. That's honest HP and unless his chassis and chassis tuning is spot on the money, he'll be hard pressed to use that power.

Exactly why that got posted. But the Super Victor may not need to be employed here on a heavy street bound car. And this my RPM suggestion.
RAMM’s build (https://www.forabodiesonly.com/mopar/threads/360-street-strip-bruiser-dyno-results.278177/)
is very very similar to what I did a while back with minor differences in the basic package. RPM, 750 cfm, 1.5 comp rockers, ported Edelbrock heads & a rpm intake are the main things.
Backed by a 4spd, it moved out nicely.

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!

I’ve rode the Dragon on my Sporty. Beautiful place, dangerous place.

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 ...

Yup! That’s the basic combo of the next build right there!
(Or a 340 block of one sonic checks well.)
Where is that builds thread?!?!

With a six pack of course or it wouldn't be right!

Of course!!!!!
 
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