do you gain any horsepower by going from the stock 400 rods which is 5.4 to 6.0 inch rod if there are any gains what do you think
longer connecting rod
- Thread starter Twister79
- Start date
What are you using the motor for?
And any power adders?
A 5.7 at min is good choice. Long may or may not befenfit.
Need more info.
And any power adders?
A 5.7 at min is good choice. Long may or may not befenfit.
Need more info.
rods
like Supe said.........no
but if you do want to run 6" rods get ready for doing alot of clearancing to block..
Supe said:
like Supe said.........no
but if you do want to run 6" rods get ready for doing alot of clearancing to block..
hmm
Stock 400 is 5.565 I think.............so going to 5.7 isnt a huge leap and then going to 6.0 isnt worth the headache.
A local guy wrecked his 400 block by grinding into the lower waterjacket when trying to clearance his block for 5.7 H beams.
For a street engine, forget about it.
Perry
Stock 400 is 5.565 I think.............so going to 5.7 isnt a huge leap and then going to 6.0 isnt worth the headache.
A local guy wrecked his 400 block by grinding into the lower waterjacket when trying to clearance his block for 5.7 H beams.
For a street engine, forget about it.
Perry
Here I go under the bus 
Put as much rod in a motor as practicle. Practicle meaning, stay out of the water jackets and the oil ring land.
Every one knows a 350 rev's better than a 400 right? look at the rod stroke ratio's
5.5rod divided by 3.78 stroke = 1.48 (stock 400)
5.7rod divided by 3.48 stroke = 1.63 (stock 350)
6.0rod divided by 3.75 stroke = 1.60 (long rod 400)
Piston speed is slowed down with a longer rod, rod angularity is reduced. Piston location is changed in relation to crank angle. The longer rod a motor has the less Dynamic compression. Which means more compression available on pump gas.
Mahle's new 6" rod piston uses thinner and better rings which keeps the pin out of the oil land.
Good stuff.
Put as much rod in a motor as practicle. Practicle meaning, stay out of the water jackets and the oil ring land.Every one knows a 350 rev's better than a 400 right? look at the rod stroke ratio's
5.5rod divided by 3.78 stroke = 1.48 (stock 400)
5.7rod divided by 3.48 stroke = 1.63 (stock 350)
6.0rod divided by 3.75 stroke = 1.60 (long rod 400)
Piston speed is slowed down with a longer rod, rod angularity is reduced. Piston location is changed in relation to crank angle. The longer rod a motor has the less Dynamic compression. Which means more compression available on pump gas.
Mahle's new 6" rod piston uses thinner and better rings which keeps the pin out of the oil land.
Good stuff.
My new answer on this topic is, : :roll:
My advice is, don't put a rod in it that will need a seat for the oil ring on the street.
Some general info: (short rod ratio 1.6, long rod ratio over 1.7)
A short rod pushes on the crank harder so therefore makes more torque
A short rod spends less time at TDC so it is less prone to detonation
My advice is, don't put a rod in it that will need a seat for the oil ring on the street.
Some general info: (short rod ratio 1.6, long rod ratio over 1.7)
A short rod pushes on the crank harder so therefore makes more torque
A short rod spends less time at TDC so it is less prone to detonation
rods
Man this is to funny,,,
I am a moderator on another site and i just told another moderator not more then 30 minutes ago that i have not seen the connecting rod fight for a good 6 months!!!!! I am kind of new here,but i am guessing by the few posts allready the war has been fought on this site also???????
Twister 79, to answer your question..No...
Also as bigtime pointed out in a street engine you don't want the pin into the oil ring....
Keith
Man this is to funny,,,
I am a moderator on another site and i just told another moderator not more then 30 minutes ago that i have not seen the connecting rod fight for a good 6 months!!!!! I am kind of new here,but i am guessing by the few posts allready the war has been fought on this site also???????
Twister 79, to answer your question..No...
Also as bigtime pointed out in a street engine you don't want the pin into the oil ring....
Keith
Since I've thrown myself under the bus already. I new this site's general belief was longer rods aren't worth the extra work. While I agree with the previous posted information, Every 3.75 stroke motor I've built has had at least a 5.7 rod. Maybe we should move this over to Advanced Technical and wade in a little deeper????
