340 or 408?

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How many rpm’s would I have to turn a pump gas 340 to run 10.00 @ 135 in my 3290# Dart.
Depending how efficient you can build it 1.25 vs 1.35 vs ? Lbs-ft per cid can make a big difference.

Say 1.3 lbs-ft and say you need 625 hp (by an online calculator).

345 cid
(625 x 5252) / (1.3 x .9 x 345) = 8,132 rpm

408 cid
(625 x 5252) / (1.3 x .9 x 408) = 6,876 rpm

Around those rpms would be my guess.
 
Define a tractor engine? My 434 has turned 7800. Tractor engine?

Come on dude. Don’t go there. You aren’t running the horrible cylinder heads and you are not.

So knock off the bullshit.

You know ******* well these 400 plus inch engines with production based heads are nothing but tractor engines.

We are taking about the street stuff these guys are doing.

And yes, race engines start at 8500. Anything else is just bracket ****.
 
Define a tractor engine? My 434 has turned 7800. Tractor engine?
Stroked, tiny bore, under headed and under cammed and done at 5000 rpm, loads of torque little horsepower.
Your 434 is a classic example of a well thought out engine, those Indy heads will make some real power far above a tractor stroker.
 
Come on dude. Don’t go there. You aren’t running the horrible cylinder heads and you are not.

So knock off the bullshit.

You know ******* well these 400 plus inch engines with production based heads are nothing but tractor engines.

We are taking about the street stuff these guys are doing.

And yes, race engines start at 8500. Anything else is just bracket ****.
It is a street car. Yes, it has Indy heads. My Edelbrock headed 408 ran 6.57 @ 104 with a flat solid on pump 93 at 3240# with Edelbrock heads. It got driven on the street a lot.

I love 340’s and have one, it ran 7.24 @ 94 and 11.60 @ 116 with a flat hydraulic cam and Edelbrock heads, 3240# on pump 93.

You have small block stroker experience?
 
It is a street car. Yes, it has Indy heads. My Edelbrock headed 408 ran 6.57 @ 104 with a flat solid on pump 93 at 3240# with Edelbrock heads. It got driven on the street a lot.

I love 340’s and have one, it ran 7.24 @ 94 and 11.60 @ 116 with a flat hydraulic cam and Edelbrock heads, 3240# on pump 93.

You have small block stroker experience?


Yes. Lots of it. I won’t use a 4 inch stroke in anything.

And I’m sure I’ll have another one on the dyno soon.

I get it. Some guys haven’t learned (and probably never will) that rpm IS horsepower.

I will shift my 340 at probably 6800. That’s street/strip car stuff.

At 7800 you are what I consider a strip/street car.

There probably isn’t 20 people on the entire forum who would want 7800 rpm for anything.

They fear rpm.

They went full Rip Van Winkle and slept through the era where valve train caught up and 7800 for even a decent build.

Using parts like you have you might as well be turning it 6500. Guys don’t get that.

I suppose those who slept through the late 90’s spent their time and money on delay boxes, 9 hit cross over boxes and throttle stops.

That’s on them.
 
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She thinks my tractor's sexy!!

IMG_1735(1).jpg
 
Cool. What did your 4” engines run and at what weight? Fuel?


None of them are mine. Again, I don’t do 4 inch strokes.

You aren’t an engine builder so take your dick measuring contest somewhere else.

Just for you, my first 408 in 2000 went 540 hp at 5200 on a hydraulic roller.

With a mild solid roller at moving peak power to just 6k would have put it over 600 hp.

And it’s STILL a tractor engine.

The stroker guys all pee their pants if you even suggest all that stroke doesn’t mean **** without rpm.

Unless it says John Deere on it.
 
None of them are mine. Again, I don’t do 4 inch strokes.

You aren’t an engine builder so take your dick measuring contest somewhere else.

Just for you, my first 408 in 2000 went 540 hp at 5200 on a hydraulic roller.
What do you have and what has it run? Weight? I’ll leave the dick measuring to internet experts like you.
 
None of them are mine. Again, I don’t do 4 inch strokes.

You aren’t an engine builder so take your dick measuring contest somewhere else.

Just for you, my first 408 in 2000 went 540 hp at 5200 on a hydraulic roller.

With a mild solid roller at moving peak power to just 6k would have put it over 600 hp.

And it’s STILL a tractor engine.

The stroker guys all pee their pants if you even suggest all that stroke doesn’t mean **** without rpm.

Unless it says John Deere on it.
I have no problem with short stroke engines, only internet experts.
 
lol. Ok smart guy. I have nothing. I just lie on the internet.
Not calling you or anyone else a liar, your stuff probably runs hard. The opinion that it’s my way or the highway is what sticks in my craw.

You are right, I’m not a engine builder. I do build all of my stuff, engines, transmissions and fabrication. My hat is off to you sir.
 
Not calling you or anyone else a liar, your stuff probably runs hard. The opinion that it’s my way or the highway is what sticks in my craw.

You are right, I’m not a engine builder. I do build all of my stuff, engines, transmissions and fabrication. My hat is off to you sir.


Let me make it simple for you.

A guy says he wants to run his 4.56’s and build a 340 and all you short dick clowns come out of the woodwork and tell him how stupid he is and how great an under headed 400 inch tractor motor would be for him.

That’s THE issue.

Don’t talk to me about engine building until you can do a valve job and tell me why you did it.

Get there and we can have a conversation.
 
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