Stock internal 318 redline??

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madjak.06

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I've got a 74' Duster with the original 318 that's had the top end replaced with mostly eddy performance parts, (alum. 4 bar intake w/600 cfm carb) along with hedman shorty headers and most importantly, an aftermarket cam *unknown lift/duration, I assume similar specs to a 340/360 cam* Other than that it's completely stock from the heads down. Car has 3.55 gears if that makes a difference-

Anyone know where the redline would be?

-Car likes to naturally shift at 4700 from 2nd into 3rd with the kickdown properly adjusted, but it feels like the powerband can go a ways further still.
 
madjak.06 said:
I've got a 74' Duster with the original 318 that's had the top end replaced with mostly eddy performance parts, (alum. 4 bar intake w/600 cfm carb) along with hedman shorty headers and most importantly, an aftermarket cam *unknown lift/duration, I assume similar specs to a 340/360 cam* Other than that it's completely stock from the heads down. Car has 3.55 gears if that makes a difference-

Anyone know where the redline would be?

-Car likes to naturally shift at 4700 from 2nd into 3rd with the kickdown properly adjusted, but it feels like the powerband can go a ways further still.
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Depends of valve springs when valve floats starts, as for the rpm the engine turns before harm Fairly high but not much need to spin past 5500 rpm or so.
 
Are you saying it has Edelbrock heads or stock heads? With stock heads it's unlikely there is anything left to get above 5000rpm.
 
It would also depend on how many miles you have on the bottom end. If it has 200,000 miles I sure wouldn't rev it to five grand. But if it's fairly fresh I'd twist the thing clear up to 6500 or more.
You have to understand I love the sound of a small block Mopar at 7500. LOL
 
I had my 1st 68 dart 270 318 650 vs 727 3.23sg headers 2 1/2 exhaust g-60-14 5500 drive atleast 50 times woudnt pull any farther
after 5300 it took for days
that was before 2.02 340 heads and the street hemi cam i was still scared to rev it over 6200
i let someone run it down the street so i could listen my brother said he tached it to 7k in 1st dont think so with stock 340 red stripe springs
it sounded real good either way
 
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Download a g-meter app based on the accelerometer chip (screen rotates), - not gps.
Tape the phone by the tach, shift point is just before the g's drop, can be different in every gear .
Cheers .
 
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I know small blocks rev, but if in my case the engine has been built and been on the dyno...
My 318/390 made it's most torque and H.P. less than 5000 RPM, so doesn't make sense to rev the crap out of it unless it keeps making power! Just my 2 cents.I shift at 5000
 
It does have stock heads, and I do plan on putting a set of trick flow heads on as well as some kb pistons at some point if budget allows... I appreciate everyone's responses and wiill set the shift point at 5000 until I can do a full rebuild! :thankyou:
 
CUDACOX said:
I know small blocks rev, but if in my case the engine has been built and been on the dyno...
My 318/390 made it's most torque and H.P. less than 5000 RPM, so doesn't make sense to rev the crap out of it unless it keeps making power! Just my 2 cents.I shift at 5000
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If you're making the most power at 5000 why wouldn't you rev it past that so when you shift it drops back into your power band instead of below it or at the bottom of it. Just a question.
 
When shifting 1st to 2nd you got .59 drop so 5000 to 2950 or say 5500 to 3245 rpm's even though your probably making less hp at 5500 than 5000 but it's a lot more than 2950 rpm hp, even though 3245 rpm is only slightly better the more time you can spend around peak the better.
Each car is gonna have it own optimal shift points you got to play around. Even if it's just in the streets.
 
a-bodyguy said:
I had my 1st 68 dart 270 318 650 vs 727 3.23sg headers 2 1/2 exhaust g-60-14 5500 drive atleast 50 times woudnt pull any farther
after 5300 it took for days
that was before 2.02 340 heads and the street hemi cam i was still scared to rev it over 6200
i let someone run it down the street so i could listen my brother said he tached it to 7k in 1st dont think so with stock 340 red stripe springs
it sounded real good either way
Click to expand...
I know my 340 sounds SICK spooled up!
 
madjak.06 said:
I've got a 74' Duster with the original 318 that's had the top end replaced with mostly eddy performance parts, (alum. 4 bar intake w/600 cfm carb) along with hedman shorty headers and most importantly, an aftermarket cam *unknown lift/duration, I assume similar specs to a 340/360 cam* Other than that it's completely stock from the heads down. Car has 3.55 gears if that makes a difference-

Anyone know where the redline would be?

-Car likes to naturally shift at 4700 from 2nd into 3rd with the kickdown properly adjusted, but it feels like the powerband can go a ways further still.
Click to expand...
What does it rev to? We can't tell you from here.
 
toolmanmike said:
What does it rev to? We can't tell you from here.
Click to expand...
I have no clue. I've had it pinned at a buck 20 and the car was climbing past 5000 with a bit of room to spare. Just from tone alone I think the motor has held 5200 rpm during burnout at 3/4 throttle. In some other chat threads I've seen some smarter people than myself calculate the absolute MAX rpm for a stock teen' to be 6200+ but of course that's if I were to melt the pistons or send a rod haha!
 
There's basically 3 areas

powercurve

valvetrain stability

rotating assembly ability to survive second/minutes/hours etc.. generally were only asking a few seconds o high rpm which is a lot less demanding than hours like a nascar race.

My cousin ran a stock 318 short block as a temp engine for late model car pulling 7000 rpm without any damage.
 
madjak.06 said:
I've got a 74' Duster with the original 318 that's had the top end replaced with mostly eddy performance parts, (alum. 4 bar intake w/600 cfm carb) along with hedman shorty headers and most importantly, an aftermarket cam *unknown lift/duration, I assume similar specs to a 340/360 cam* Other than that it's completely stock from the heads down. Car has 3.55 gears if that makes a difference-

Anyone know where the redline would be?

-Car likes to naturally shift at 4700 from 2nd into 3rd with the kickdown properly adjusted, but it feels like the powerband can go a ways further still.
Click to expand...
Hold it in low until you want to shift then 2nd and 3rd.
 
Jadaharabi said:
There is no problem with hydraulics at 7500.
It's in the valve springs.
Click to expand...
Back in the seventies I had a 340 six pack 4 speed manual trans with forged pistons 292/510 purple shaft cam and heads were just home clean up of the ports and valve job at home by my father. That thing was a rev monster! After running it in I took it for a run down the road and it pulled past 6500 on the tacho before I changed in every gear. I would rev it well over 7 grand when showing off but max power was at about 6500.Yes it had Hydraulic lifters and std rocker arms.The hdro lifters were not stock but out of a drag car of the time 383 two barrel that ran low tens. Looking at them you could see where the oil hole had been welded up and moved but I did not know if the internals had been modified but you could easily get to mid seven thousand revs. No one could believe how that thing could rev with hydraulic lifters.
 
madjak.06 said:
similar specs to a 340/360 cam*
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the 340 cam was a 268/276/114
With the matching 340 springs it made peak power around 5000. More often than not, the springs would start to give up around 5400. But with a lil more spring, would get closer to 6000.
Your engine has at least two or three so called, redlines.
The first relates to piston speed.
The second is the so-called valve-float
The third is actually the optimum shift-rpm.
>I don't remember the formula for piston speed, but for a 318, it's probably way up there, past valve float.
>Valve float you can usually feel when you power into it, and you want to stay away from that, cuz if the valves get into the pistons , they are done. This varies with the springs and lobes.
> Optimum shift-rpm has already been explained.The thing to remember is with a Chrysler automatic, it will be different in each gear, cuz the splits in the trans are different.
On the street with 3.55s, it matters not a whit; just pick something below valve float and let her buck.
 
madjak.06 said:
I have no clue. I've had it pinned at a buck 20 and the car was climbing past 5000 with a bit of room to spare. Just from tone alone I think the motor has held 5200 rpm during burnout at 3/4 throttle. In some other chat threads I've seen some smarter people than myself calculate the absolute MAX rpm for a stock teen' to be 6200+ but of course that's if I were to melt the pistons or send a rod haha!
Click to expand...
If you limit it to 5000 and it holds together you're good. If you rev it to 6500 and it blows, you know you went too far. There is no magic number.
 
My last stock 69' 340 aluminum intake and edelbrock 4barrel scattered itself at 6800 but that was bone stock heads/valve train but man it sounded great until it didn't. Now its .030 and 3 sleeves and I shift it at 6000 in a 67 B body. With 3.23 gears.
 
My guess (note:Guess) is that the bottom end is probably safe to 6000/6200. Whether there is ANY point going there, or even trying to get there, is determined by head flow and camshaft/valvetrain.
Stock cam and springs? I see no benefit past 5200. Maybe less.
 
AJ/FormS said:
>I don't remember the formula for piston speed, but for a 318, it's probably way up there, past valve float.
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The easiest way is divide 24,000-30,000 by stroke = max rpm, depends on parts and build quality,
24,000 is a decent built short block, 30,000+ is like nascar, 24,000 divided by 3.31 = 7250 rpm.
Being stock might want to shave off some rpms.

Max pistons speed x 6 / stroke = max rpm
 
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