low emission '72 340Ci engine question

[CB]

they started to kill the engines from '72 and later
when you rebuild a 340 (# matching to the car) what performance you could gain on a low compression block?
I tried the search option but nothing came out so far.
thanks
CB

[oldkimmer]

............U CAN MAKE THEM PRETTY STRONG NOW, with all the new light weight parts and coatings out there............kim........

[Nacho-RT74]

just get a high compression piston and will be on earlier numbers... right ? I think that's so easy with that motor ! only 400 owners have poor options

[dads_69]

CB, what exactly are you wanting to build, a street motor or street/strip? I've built a few 340 motors. The one I have now is a  377 stroker.
10.7 to 1 comp. Forged Ross
two cams so far 493 Lunati & 509 Mopar performance
J head that are worked
5 intakes from single plain to dual
770 Demon carb & 700 Holley vac. sec.
1 5/8 TTI headers and factory 340 H.P. mainfolds
MSD ign.
My year block is a '68 other was a '69
You can build a close to spec 340 6 pak motor pretty easy from Summit Racing or Jegs for under 2500 bucks.
I had a set of Edelbrock aluminum heads but sold them w/my 340/408 stroker last year. It was  fast motor for a A body.
340 motors were low comp. till 1973, but still very strong when built regardless of year of block.

Hope this helps.

Mark

[Ghoste]

Along with the compression drop, didn't they also give them a head with smaller valves and ports?  In any case, Nacho is right, a piston change and maybe some Eddy heads and a cam like dads recommended and you'll have a pretty stout little mover.

[CB]

thanks for the feedback!

I googled around and read this article on Wikepidea:

Performance Characteristics:
Like many other performance V8's of the day, for insurance reasons, the 340 engine was underrated at 275 hp (205 kW) with a single four-barrel carburetor and 290 hp (216 kW) with three two barrels. However, in reality both configurations could produce at least 315 to 320 hp (235 to 239 kW). On the street, the 340 delivered as promised. The engine was simply a screamer and many a big block driver found themselves shaking their heads after being beaten by the little Chrysler small block. Within the Chrysler family, the 340 gave nothing away to the 383 on the strip, and totally outclassed it when it came to handling. When coupled with lightweight A and E-Bodies, the 340 setup was a born street-fighter that was equally at home on the track. The engine was praised as a high-winder with good durability, making it popular with circle-track racers. The most potent street version was the "Six Pack" 340, found in the Challenger T/A and AAR 'Cuda.

I am checking the comparison to the stock 383/440 big blocks.
Sometimes people act disdainful on small blocks. And ok, BB give have more torque.

I believe from what I read a good standard/stock rebuild 340 would be a reliable, 300+hp, good torque, screaming, fast street engine.
No need for stroking the engine, right?
CB

[dads_69]

CB, check out this website for more info. and look for the small block build guide. I have the book myself, very informative for what you want to build.
www.cartechbooks.com and look for *how to build big inch mopar small blocks*
Mark
Edit. no, need to stroke a small block, basic rebuild to 1970 specs would be okay also, maybe a tweaked set of heads or aftermarkets also w/10 to 1 slugs and decent cam/carb and dist. 300 H.P. should not be an issue.

[CB]

Edit. no, need to stroke a small block, basic rebuild to 1970 specs would be okay also, maybe a tweaked set of heads or aftermarkets also w/10 to 1 slugs and decent cam/carb and dist. 300 H.P. should not be an issue.

It's a matter of keeping the project numbers matching.
The project I am hopefully buying has all numbers matched.
First time of all the cars I had in the past so that's why I see it a little as an 'investment'.
If the 340 is completely build to stock specs (with stock heads/cam/...) what kind of engine you got?
CB