That equates to 290 hp at 3300#'s.
Horsepower Estimate?
- Thread starter 3RD Duster
- Start date
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I ran a torker with spray on 3 engines the tm5 is about the same
318 340 heads street hemi cam torker door stop headers 2.5 exhaust 3.23sg 727 spray and a unilte dizzy that setup won me alot of money in early 80s more then the car cost and mods
The cuda is stock 340 with tm5 and carb the 700 dp is what it should have had stock not the 585 cfm pos
I ran 3 or 4 of those carbs it was the 1st thing to go
ir3333
Well-Known Member
That's great info with actual results!
My Torker was on a stock 340 and worked just fine. Stock heads stall out around
.485 lift at about 190 - 200 cfm so it looks like a good match... but these are figures i have only read.
When racers post with real info it is helpful for sure. I have no racing experience.
My Torker was on a stock 340 and worked just fine. Stock heads stall out around
.485 lift at about 190 - 200 cfm so it looks like a good match... but these are figures i have only read.
When racers post with real info it is helpful for sure. I have no racing experience.
just so you know 92 mph@ 3600lbs gets your 383 road runner or 383 dart 216 hp using that calc
my 68 gts was 3420 without me in it
my 70 duster 340 4spd was 3610 with me in it
Yes and the dyno vid i posted the door stop made more power then the other intakes after 4600 or 4800 and was only 3 less then the strip dom
Guys running low 10s on this site using the door stop
Don't think the OP is looking for an exact number just what it more than likely could be on a dyno tuned right. Who knows what it is actually in Net hp (as is in car). If I was the OP I'd say around 350 hp, does it really matter if it's 330 hp or 370 hp or somewhere in between. Now if it's only 250-290 hp and saying 350 hp I'd say saying 350 hp is wrong then.
I don't get why people think those calculators are more accurate then a dyno, any other time a rule of thumb or a formula is brought up it's dismissed as nonsense or at best a huge ballpark area. And since the dyno is supposedly unreliable there's no way to verify these formulas plus there's like 5 of them and they don't even agree with one another, to me they seem to tell you minimum hp needed if everything is setup a 110%.
So every car that weighs X lbs and goes Y mph is the exact same hp, I don't think so. What about the rest of the hp curve don't matter ? Same with tires, gearing, stall, aero, driver etc.. ?
Imagine what the rest of the muscle cars had for real hp if the 340 only had 280 or 290
sucking the paint off 383s some 440s 390 ford 390 amc 400 gtos 396 chevelles easy some 375hp 396s
mopar under rated the 340
chevy over rated there engines
289 ford hipo engine way over rated 235 stock slow as piss and weighed zilch
383 mopar over rated big time
454 ls-6 didnt make the number without headers
buick engines legit 455
455 poncho legit
440 4 barrel close to legit
dz302 dog motor below 5k rpm
boss302 dog motor below 5500 rpm
t/a 340 6pk sucked the paint of those stock quarter mile t/a 14.0@100 the boss and dz302 ran 15s thats 10 car lengths
sucking the paint off 383s some 440s 390 ford 390 amc 400 gtos 396 chevelles easy some 375hp 396s
mopar under rated the 340
chevy over rated there engines
289 ford hipo engine way over rated 235 stock slow as piss and weighed zilch
383 mopar over rated big time
454 ls-6 didnt make the number without headers
buick engines legit 455
455 poncho legit
440 4 barrel close to legit
dz302 dog motor below 5k rpm
boss302 dog motor below 5500 rpm
t/a 340 6pk sucked the paint of those stock quarter mile t/a 14.0@100 the boss and dz302 ran 15s thats 10 car lengths
Here a 340 six pack it's not totally 100% stock unfortunately vs the performance sb Chev and Ford offerings.
Yes but mph and weight will tell you this
at that mph at that weight the quickest you can go is X et
nothing is more accurate then that
period
That is what the dc chart that was posted shows 98 mph gets you 13.0 if traction gearing and everything is perfect
few and far between can run the ets for those given mph
PRH
Well-Known Member
My thoughts are the opposite of that.
But I’ve been using the dyno since 1990.
When I want to know how much power an engine makes, I test it.
Built in 1987-
340+.030, Badger stock replacement pistons for 68-71……actual CR unknown.
587 heads with 2.02’s installed. Using the term “bowl ported” to describe the work done to the heads is very generous.
It was the 2nd set of heads I’d ever taken a grinder to(back in like 1987).
My guess would be 210-ish cfm.
Regular Performer, Holley 650, 1-5/8” headers, Comp 268H.
What did it make?
Back story on this 340……
When it was built originally in 87, it got a bigger cam.
A Crower 282-HDP.
The engine went into a LRE truck, and even with the 3.55’s and an 11” converter…….the cam was a bit too much for the application.
Fast forward into the 2000’s, and it’s been thru a couple owners……None of which are really “car people”.
It ends up ingesting the air cleaner stud…….which gets into a cylinder. Munches up the piston and puts a crack in the bore.
A friend of mine with a repair shop is working on the vehicle……..he brings me the engine.
I end up sleeving the block, and getting a “similar” piston(Badger is long gone and there aren’t any other cast pistons with the same specs).
Cam lobes are showing some wear by this time, and the heads need freshening.
So, heads get done, and the Comp 268H gets the nod as a more suitable replacement given the application and intended use.
I dyno tested it after the repairs.
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PRH
Well-Known Member
Yup.
Even though fishermen says iam on crack
My 68 gts 85kmiles 340 727 3.23 ran 14.3@97 every time all stock
Drivetrain came out went in my 67 dart vert
top end was tired was smoking@100k or so
put in comp 268h 218@50 454 lift fresh 2.02 j heads x heads were tired weiand stealth tuned 650 dp unilite dizzy 38 yrs old and counting
comp test highest 169 psi 6 163 to 166 1@157
stock rings bearings 100k miles
3.91s now not 3.23s
The car rips for 100k mile lower end id guess 13.6 now@102 or 103
edit
I did use the thin head gasket
calc says my comp ratio is around 9.99
My 68 gts 85kmiles 340 727 3.23 ran 14.3@97 every time all stock
Drivetrain came out went in my 67 dart vert
top end was tired was smoking@100k or so
put in comp 268h 218@50 454 lift fresh 2.02 j heads x heads were tired weiand stealth tuned 650 dp unilite dizzy 38 yrs old and counting
comp test highest 169 psi 6 163 to 166 1@157
stock rings bearings 100k miles
3.91s now not 3.23s
The car rips for 100k mile lower end id guess 13.6 now@102 or 103
edit
I did use the thin head gasket
calc says my comp ratio is around 9.99
I'm not trying to change your mind think whatever you want. I just don't agree.
How's a 360 with modded 318 heads, and a cam about the stock size as a 340 cam with a terrible intake anything like the OP's engine? And it even made 305 hp.
Let's put a mild 8.2:1 360 on the dyno.
I think the 340 build up I showed is a little more in line with the OP's engine.
If Jim's thread doesn't support this 340 making more than 300hp if everything was in decent shape, not sure what would convince folks.
@PRH
Had a 360 with a 214/224 cam. Car ran high 11's at 3000# Sounded like grandmas 318 Duster.
Nothing will convince people to change their minds, if they aren't open to receiving, evaluating, and acknowledging new information.
Some people are just stuck in their ways and perceive everything that doesn't 100% agree with them as some kind of personal attack. They just go into fight mode and choose ignorance over enlightenment.
autoxcuda
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That IQ52 motor was 297 hp. much smaller cam 260H (comparable to stock +/-)
OP motor has significantly bigger cam, RPM intake, and probably comparable heads (IQ52 put 1.88/1.60 in 318 heads w/throat work), "650" Holley (IQ52: 1850 Holley)
Sounds like Crackedback guestimate of 300-350 seems pretty safe.
Which exact 650 Holley the OP has might be significant to know. Is the 4150 style 650 significant improvement over the 600 1850 style?
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Newbomb Turk
Well-Known Member
Claiming a time slip is the most accurate way to determine horsepower is just not true.
The chassis could be bending like a paper clip. The converter could be wrong.
The tires could be junk and maybe, just maybe the shocks and suspension could be whacked.
A time slip is only as good as what you are working with, which is no different than using dyno numbers.
PRH
Well-Known Member
Drag strip vs dyno……
When my friend went from an auto to a stick in his nhra stocker the car picked up 4mph.
On the Moroso chart that shows a 50hp difference.
A 50hp gain without changing anything on the engine?
Uh…..no.
When my friend went from an auto to a stick in his nhra stocker the car picked up 4mph.
On the Moroso chart that shows a 50hp difference.
A 50hp gain without changing anything on the engine?
Uh…..no.
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