From experience with a strong 340 and data of the 5.7 hemi, how do you compare the 2 regarding performance ???

A strong 340 can put out 400hp easy, while the new 5.7 hemi pulls 345 hp ???
wich one has more performance in real life ??

How can you compare the 2 ??

Dan

A stroked 340 would be faster than a stock 5.7 hemi. You can get 500hp out of a 416 and still street drive it.

You can modify the 5.7, just like any other engine, but the parts are going to cost more.


EDIT:

Your title says stroker 340. Is that what your asking about or just a stock stroke 340?

So is there that much difference between the 2 engines in stock form ?

If you buy a complete 5.7 and run a carb and computer from XV, about the cheapest you can get all away with looks like around $5000 absolute best case scenario and HP will be around 400, the carb and headers 5.7 will make around 400 hp out the box.

For $5000 you can build quite a hot 340 stroker and make way more HP than 400. I am building my own 340 stroker for my 68 cuda and with home ported aluminum magnum heads, 1.7 mopar roller rockers, billet crower rods, wiseco pistons, forged mopar perf. crank, eddy arigap intake, comp XE268 cam TTI headers, rings, bearings, gaskets 770 street avenger or 850 T-quad I will have less than $5000 in it and I should be close to 500 hp and WAY more tq than a 5.7 could ever make with out spending big $$$ strokeing it, porting, caming... in a bucks down build the 5.7 stroker can run R E A L Y hard though! The ports flow as much OOTB as mine will ported, they have nice uniform thick bores and cross bolted mains. The 5.7 block is as good as some of the aftermarket small block blocks, the stock heads are better than SB eddys to boot

If you want EFI then the hemi will cost more also especially since your car is now wired for the SB injection.

If I was you I would build a stroker 5.2 or 5.9 magnum so I can use the roller cam and your existing injection set up.

You would have to get your computer reprogramed but the wiring can all stay.

As usual, well said and explained Dave...

Thanks

Daniel

For right now the aftermarket for the gen3 hemi isn't close enough to what is available for the 340. Then again calling the small block Mopar a small block is kind of a stretch. Take the block measurements into acount and compare them with their brand x competitors. Our block has a gargantuan crank case that, depending on rod selection, will swallow a 4" stroke with no grinding at all. Try that with the others. On top of that the cam centerline is so tall you'll never have to worry about rod to cam clearance. The deck height is big block sized too. Then our heads start off at 18 degrees, so even with the tight confines between the pushrods, the flow stays high. In short, Mopar is where its at.

As far as pound for pound, hands down performance, I can't see ANY small block being able to compete with the new hemi. For one it's a hemi and physics and science, not to mention new tech, is on its side. I would love to see how an all out stroked new Hemi would hold up against a 472ci R3 small block with W9 heads. I bet it could really hold its own.

The aftermarket is starting to catch on to the new Hemi. I can't wait to see where it goes.

Ported 6.1 heads are easily going over 320 cfm. That is easily into max effort W2 and W5 teritory. Heck even ported 5.7 heads are getting 300 CFM pretty easily. They won't keep up with a W8 or W9 but they are after all "just a stock head"

I think the limit on new hemis in an all out deal are you can easily go to about 425 inches, any more requires exotic stuff like honda rods custom cranks custom pistons... and the rocker selection is pretty much limited to stock right now and while they are good they aren't "that" good. They are maxing out around .600 lift witch ain't too bad considering how much they flow even at that low of a lift but it limits max HP. Between the rockers limiting RPM (non adjustable)and cylinder walls limiting cubic inches they are reaching there limits (for now).

That is so cool! As soon as racers really start catching on our problems will be solved.

Where is a good souce of tech info on the new Hemi?

i think all the new hemi needs is a little time. you have to remember that its competition right now is the LS1. it has alot to catch up with considerin the LS1 has been on the assembly line since 98. and this year mopar gave us a new hotrod to work with. but man its a hemi. nothing accepts superchargers any better. no engine looks as cool a blown hemi. and the 3rd gen has cross bolted mains and bada$$ aluminum heads from the factory. and as usual the thing needs valve train work. personally i feel its just a matter of time before someone starts using it for one of the outlaw classes.

New Hemi ALL THE WAY!

If I was starting from scratch, it would be a GEN 3 no questions asked..In fact, I would have already built one if I didn't already have so much money wrapped into my small block and parts already.

Stock heads that flow what fully ported or race heads for a small block would? Stock blocks that can handle 800hp no problem? Lighter too! Win win if you ask me

Just my

New hemi for sure.

And I have at least 4 340s.

Have a stock hemi in our durango and I think it will outrun my edlebrock headed 10.4-1 340 that's in my challenger?

Ported Apache heads (6.4 HEMI) can go over 400, it's insane the air you can get through them. Gen III blocks will handle in the 1000 HP range.

HotRodDave, does the 340 your building include the buy in and machine work? $5K seems pretty cheap for a fully outfitted 340

I hate to bust all of your guy's chops, but this thread is from 4 years ago.

Wonder what he went with??