Hi all, just picked up a 71, 340 block down under with eng number GW340P33750229 and a stamped number near the pan rail 1B240802. Definetly not an Australian delivered 340..Just curious about its history, any help appreciated. Picture is my Aussie factory 340 Charger.

likely out of a demon or duster

3375 build date 10/24/1970

That would be a 1971 high compression Thermoquad motor, the fastest stock 340 motors made

GW340P33750229

G=1971 Model year
W=Windsor Ontario Assembly Plant
340=Cubic inches
3375=Saturday October 24th 1970
0229=229th engine assembled

Thank you.

I think the '70 340 Six Pack engine might have something to say about that.

find one and try it and see
I used to help Gene Buh l(SP?) run his NHRA stockers, the 340 6 pack Challenger was faster than his 1971 Demon 340 car, but NHRA put more HP on the 6 pack motor after he set the C/SA record with it I think they made his car have 5 more HP on that engine HP factor than the 1971 Thermoguard motor did, they didn't add the HP to the 1970 AAR Cuda, the T/A Challengers only
He ended up quitting drag racing in the stock classes after that last factoring on him, he got into 4 wheel off roading and jeep trail rallies

The 1968 340 manual trans used the hottest factory camshaft of all year 340's:

276/284 444/453.......all other years 340 automatic and 4 speed, including AAR/TA 340-6 specs are

268,276 429/444...

I have had the 68 manual camshaft in my otherwise stock 71 340 4 speed Cuda since 1976 and with the thermoquad I have the best of both worlds...works amazing.

How many CFM does the stock 1968 340 Carter AVS flow?
How about how many CFM on the 1971 Thermoquad?
All the 1971 340 are rated by NHRA to be higher in HP than the 1968 to 1970 340 engines and the 1972/1973 340 motors for a reason, it ain't because of the camshafts

I totally agree the themoquad is the far superior carb, I never claimed a 68 340 was the faster stock 340 motor

just mentioned the hotter camshaft with specs that was mated to my 71 thermoquad motor.

I also ran a 1000 CFM cheater thermoquad for a while with that motor

I recall NHRA rating stock 340's in 71 at either 310 or was it 325 HP.

I'm speaking from personal experience. Back in the mid 70's I had a '69 Swinger 340 car that I put a Holley 800 spread bore on and it ran the best of 13:22. Later I installed a six pack set up and the Dart instantly ran a best of 12:88 at 114 mph. The only thing done to the engine was a cheap 500 lift, 300 duration hyd. cam from JC Whitney and full length headers. I had a B&M 3500 Super Holeshot convertor and Zoom 513 gears.