340 dynoed

-
gzig5 said:
Nice build! Got to be some special satisfaction getting a good number like that when you put some sweat into the porting. I just finished a little hotter build that used some newer/lighter parts for 458hp, but I have a spare 340 block, crank, 2.02 J-heads, heavy forged pistons, etc still left over that were collected over the years. When I get caught up, I want to put something similar to yours together if nothing else, just to play with. I guess I need to talk to Clay Smith about a cam too. I missed him when I was looking for a grind a couple months ago.

What's the motor going into?
Click to expand...
I'm putting it in to a 66 belvedere with a 4 speed and 3.91s.
 
PRH said:
Nice numbers!

Is that R&R in Minnesota?
The reason I ask is I’ve seen dyno sheets from an R&R out there, but the sheets looked different.
New dyno data acquisition system perhaps?

Edit- I did some “googling”.
The logo on your sheet looks the same as the shop I was thinking of.
That place does a lot of dyno work.
Click to expand...
Yep, I've had them do many engines.
 
Sweet little street car engine, don't believe you will be disappointed.
 
I had a not too dissimilar 360(9.7, mild 2.02 J heads, LD340 + 750DP, small SFT) on the dyno here a few years back.
I had freshened the heads and did a cam swap.

Made about the same hp/ci……. At about the same rpm.
 
Babyblue66 said:
Got my 340 on the dyno.
It's a 70 block, forged crank, balanced, line honed, ARP rod bolts, slightly used heavy old TRW forged pistons. Calculated out to 9.7 to 1. J heads I ported a little. 2.02, 1.60 valves. Clay Smith 292 240 @ .050 .472 lift on a 108 lsa installed at 106 solid flat tappet single pattern "Chevy grind" according to the know-it-alls on here. 1.5 Mancini roller rockers. LD340 intake and a 750 double pumper and a 1 inch tapered 4 hole spacer. Dyno guy had 1 3/4 headers, although I'd rather have used 1 5/8.
Stock recurved electronic distributor. Nothing exotic. The rockers were by far the most expensive parts.

Best of 395 hp at 6300 and 377 tq at 4900. Runs very smooth and pulls past 6k with ease.
I was hoping for close to 400 hp so I'm happy with it.
Click to expand...
Awesome looking build. These little 340's definitely punch outside of their weight class, that's for sure. Will yours ever be run at the track? I'd be curious to see what it runs.
 
Babyblue66 said:
That's good to know. Also it has only 135lbs on the seat and we'll under 300 over the nose. Easy on the cam and everything else.
Click to expand...

maybe that's why he didn't run it past 6300? Was worried about floating valves.
Especially in someone elses new motor.
 
At the rate it's gaining hp at the top don't think a few hundred rpm more gonna squeeze out much more power.
 
9secRR said:
Street/strip builds?
Click to expand...
Mild street stuff.
One is a 66 coronet hardtop, 440 with the 2832 hydraulic. 2355f pistons, torker 2, 750 Holley dp, headers, automatic. Ran 13.15 with 3.23s and 225/75-15 street tires. Wasn't dynoed.

A 2942 whiplash in my 66 wagon super low compression 1977 440 at 7.5 to 1. Made 415hp and 465 tq on the dyno.

Built a 360 for a lady with 8.7 to 1, 2336 whiplash, made 354hp, 388 torque.
 
qkcuda said:
Any pictures of the car? I have a baby blue 66 Charger.
Click to expand...
Here's the most recent crappy Pic. It's original paint, had a few dings and dents, a lot of chips, a little fading here and there. So it's perfect for a driver. Buffed it out and Did a lot of work to the interior. Painted the dash, cluster, and pad. New carpet. Those are dodge camper van seats I sprayed to match. Also put in a new headliner. New windshield, used rear window. Patched the passenger floor and trunk. Very clean Texas car. Pretty much built out of parts I had or got pretty cheap. It's been a pretty low expense build. Paid 3500.00 for the car initially last fall.

Screenshot_20250314-224619_Photos.jpg


20250212_154235.jpg
 
Last edited:
qkcuda said:
Any pictures of the car? I have a baby blue 66 Charger.
Click to expand...
I bought a 66 charger this winter too. It was cheap and very clean. Just cooked interior that's completely disassembled. Has a pretty strong 440 in it. Not sure what I'm gonna do with it. Need to put in a windshield, fix brakes, etc etc to make it road worthy.

20250117_144837.jpg


Resized_20250309_120052.jpeg
 
Babyblue66 said:
Done at 5500? It still made 10 more hp and pulled easily up to 6300.
Click to expand...
10 hp gain over 800 rpm's ain't very much, the engine is basically just as strong at 5500 rpm as it is at 6300 rpm, but still gonna be a great engine.
 
You must log in or register to reply here.
-

Back
Top