Stock 340 dyno tests?

-
I like Nick I like watching his dyno runs, it drives the wife nuts because I commandeer the TV and watch them LOL! She's like " I don't get why you watch some guy rev an engine for an hour...LOL!"
 
My reply…. Several grunts like Tim Allen would do.
 
And another thing...the driver can make a big difference with a 4 speed.I knew a couple of guys who would win races handily....swap cars and still win.You couldn't hear them shift. I held the gas right to the floor and never let off when shifting my.
So exciting back then and we did some stupid things I don't care to remember.
 
In 1970 the factory rating would have been SAE gross. I think this should be close to dyno numbers (no air filter, exhaust, accessories)
 
Sure there aren't. The cylinder heads alone have plenty of "secrets" in them. Offset grinding cranks to the max tolerance, nope nothing special. Camshafts with loads of duration and limited lift that exceeds the OEM stick by a bunch. Where should I stop.

Ever have to go through a stack of 400-800 rod assemblies looking for good matched up sets that were on the long side? Ahhh the good ol days.

Stock elim is so off track from reality of a OEM engine. Carry on with it.
Rob dammit another one of us I'd love to meet and likely never will get to
 
Another little troubling thing I ran across in the early 70's........was reading one of the popular mags...Hot Rod, Popular Hod Rodding, Car Craft, I don't remember

Little box way WAY in the back of the mag

Said, basically, "we sometimes factor the numbers if we think the weather, the driver, the tires, bla bla bla in other words, the chevies sometimes got better numbers out of the sky because "they thought so"
 

This is my brother's car.
The heads were some j heads that IQ52
Ported for me and put 2.02 valves in
I ended up changing directions.
We thought it was good for his car to appear stock.
Let me tell you those heads flow and that car pulls !
Thanks Jim
 
Last edited:

This is my brother's car.
The heads were some j heads that IQ52
Ported for me and put 2.02 valves in
I ended up changing directions.
I thought it was good for his car to appear stock.
Let me tell you those heads flow and that car pulls !
Thanks Jim

355s 3.91s? sounds like 55s
 
Sounds like 3.55's? looks like a pretty tall tire on the back
 
How much horsepower would a solid .528 purple shaft, an Ld340, 750 holley at a very stock compression 'reality 9.5 comp' be worth .. maybe 40hp? Maybe 48hp?

People breaking down individual increases like headers and 14 to 18 horsepower increase but what's the rest of the combo that might matter, a 750 in place of stock for another 10 or 15 a cam for maybe 20-25hp..the tune itself ontop of all those... 60hp?

If we dont even know stock hp..can guess our way backwards...

believe 310-335 hp stock is reasonable.
Is this now tuned or stock tune? There's a lot to think about.
 
All I will add is I ran 14.20’s with my stock 1972 (340) 4 speed duster with 3.91 gears. Self tuned by a 19 year old punk. Suck azz street tires

Back in early 1970 my '69 340 Swinger, Torqueflite, open 3.23 gears, Goodyear Polyglass tires ran 14.28 @ 98+ mph at OCIR running G/Pure Stock.
I loved beating big-blocks on the street. They could beat me in a full quarter mile but the combo of quick-revving and light weight would get them stoplight to stoplight.
 
my 68 gts 340 auto 3.23s all stock 85k no air cleaner timming bump spring clamps the chit 68 carb
3600 lbs me in it on the line 14.3@97 mph thats 320 crank 256 rwhp pretty simple
 
my 68 gts 340 auto 3.23s all stock 85k no air cleaner timming bump spring clamps the chit 68 carb
3600 lbs me in it on the line 14.3@97 mph thats 320 crank 256 rwhp pretty simple
your et @ 14.3 is 245 hp @ crank 220@ wheel
mph @ 97 256 @ crank 230 @ wheel. mph don't lie
 

So I've shared this before.
Here is another 340 with edelbrocks ported by IQ52.
Once again they flow well and the car pulls hard.
Thanks Jim !
Jim and Cody did impeccable work !
Glad that Jim shares on here.
 
Last edited:
-
Back
Top