Replacement 68 340 four speed cams

[71GSSDemon]

My 99.9% stock 340's would run 14 flat go 165 and get about 20 mpg on snow tires with no posi. no o.d. Stock exhaust system. I have plenty of witnesses. There may be some better stuff out there but it always worked for me. Now add 1.6 rockers, 11.0 to 1, o.d. 4.10's headers etc. what would you get today. Add a high-pressure fuel system. Wow just imagine what you'd get out of that little 340 with a 55 year old cam. O, with 55 year old heads to boot. Now ...

I know you are in MI, if near Detroit, is it in Kilometers per Hour by chance? Some Canadian cars have Km/h speedos

 

[71GSSDemon]

Could always just film driving in the car then edit and speed it up to ludicrous speed...

Ludicrous speed? We have never gone that fast. Just do it. GO!!

Careful not to go to Plaid.

 

[TT5.9mag]

Ok fine. I will use the GoPro to film my Bonneville speed run this summer with a purpose built aero car to prove how slow it really is.

You know I’ll be there. Hell I might even bring my own go pro.

 

[TT5.9mag]

I believe the formula for top speed HP goes as:

($ x APR) + 5W = S x .99, where

$=$
APR = variable
5W = lodging
S = speed
.99 = "I'll be back next year" coefficient



And: I think it goes... all the power you can afford dose not go as fast as you want.

From Carroll Smith's book [Tune to Win] Drag HP= CD X Frontal area X ( Velocity in mph) to the 3rd power divided by
146,600

His example Drag HP = (.65) X ( 17 FT) x (180 mph) to the 3rd power OR 180 X180X 180
--------------------------------
146,600 = 439 HP





It is proportional to the cube of the speed. The force due to drag is proportional to the square. To get power you have to multiply by the rate. Therefore the power is proportional to the cube of the speed.

If it takes 100 hp to go 100 mph then to go 200 it is the ratio of (200/100) cubed times 100 hp or 800 hp.

Don’t let math or science or any of that other nonsensical stuff ruin a good story.

 

[TT5.9mag]

Well I'll give in. 12 Impala, little 240ci, n/a, tires do weight 70 lbs ea. Power windows, power brakes, power locks, power drivers seat, power trunk, ac, cooling ducts for frt. brakes (did I give it away?) 100% factory stock with cat conv., almost 200k, runs 14's, turns 6700, and extremely limited to 151. H.P. must be at least 650 according to the sq. root to the square root. but Chevy must have got it wrong at only 300. But 300 from a 87 octane 240ci with 280 lbs. of rolling stock? HOW? WHY? O and it does circles in city streets and much more. WHY? O yes old ppv cruiser.

With the 2012 impala numbers @junkyardhero posted I show you need about 218hp to go 151. Isn’t aerodynamics amazing? There are some assumptions here and I don’t know downforce so……..

 

[1MeanA]

With the 2012 impala numbers @junkyardhero posted I show you need about 218hp to go 151. Isn’t aerodynamics amazing? There are some assumptions here and I don’t know downforce so……..

At the wheels?

 

[71GSSDemon]

Don’t let math or science or any of that other nonsensical stuff ruin a good story.

Fouci thought us to trust the science though

 

[71GSSDemon]

The formula data sheet I made says roughly 385.6hp for a 68 Dart to do 165 based on frontal area, drag CoD, etc. And 434hp for elevation at Bonneville.

 

[71GSSDemon]

Now, once you have the HP to overcome drag, with the tire size and gear ratios...

 

[Dartswinger70]

Wow shell "fly to the moon..."

 

[71GSSDemon]

Don’t let math or science or any of that other nonsensical stuff ruin a good story.

Sorry again.....

 

[1966Post]

 

[71GSSDemon]

There was a time I had my big block Camaro out playing. 454 4spd 26" tires 2.73 gears. I passed 3 telephone poles in 5 Mississippi's which is perfectly calibrated to 120mph.

 

[junkyardhero]

The formula data sheet I made says roughly 385.6hp for a 68 Dart to do 165 based on frontal area, drag CoD, etc. And 434hp for elevation at Bonneville.

welp. case closed. eveybody knows that 340's came with 400hp from the factory no matter the vintage and no matter the day of the week they were built on!

 

[LO23M8B]

Offshore racing, no. But I do have a 21’ jet boat with a twin turbo 489 big block Chevy in it. It’ll bury the 45 mph speedometer.

cool ride

 

[LO23M8B]

There was a time I had my big block Camaro out playing. 454 4spd 26" tires 2.73 gears. I passed 3 telephone poles in 5 Mississippi's which is perfectly calibrated to 120mph.

Depends how many ss's you use. lol

 

[LO23M8B]

I know you are in MI, if near Detroit, is it in Kilometers per Hour by chance? Some Canadian cars have Km/h speedos

Maybe.

 

[RustyRatRod]

Depends how many ss's you use. lol

Yeah and how fast or slow you say Mississippi.

 

[LO23M8B]

Ok fine. I will use the GoPro to film my Bonneville speed run this summer with a purpose built aero car to prove how slow it really is.

Maybe you should use an Impala engine.

 

[LO23M8B]

From Carroll Smith's book [Tune to Win] Drag HP= CD X Frontal area X ( Velocity in mph) to the 3rd power divided by
146,600

His example Drag HP = (.65) X ( 17 FT) x (180 mph) to the 3rd power OR 180 X180X 180
--------------------------------
146,600 = 439 HP





It is proportional to the cube of the speed. The force due to drag is proportional to the square. To get power you have to multiply by the rate. Therefore the power is proportional to the cube of the speed.

If it takes 100 hp to go 100 mph then to go 200 it is the ratio of (200/100) cubed times 100 hp or 800 hp.

How come Hellcats do it with 700hp? Maybe a Monday build.

 

[LO23M8B]

Ludicrous speed? We have never gone that fast. Just do it. GO!!

Careful not to go to Plaid.

Hey, let us all know when you're going we can have a party. Give a link to the event and the rules.

 

[LO23M8B]

I'm still thinking about that 3.6L Impala.