Thoughts on a 225 rebuild

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Charrlie_S said:
Actually as far as the OP is concerned, all this discussion is mote. This discussion has turned into more "high tech" then necessary. The OP is building a mild street engine. I think he is more interested in "bang for the buck", which would leave out a long rod combo.
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Thank you, yes, I'm looking for something that has a little more power and/or efficiency over a stock, 120,000 mile super six. I don't have much cash, so I'd have to save up for this, which is why I posted this to get some ideas for a good general direction to go in.

I want parts I can buy on Ebay or at o'reilys for a long haul engine that can pull a load, if needed, but wont make my wallet cry every time I fill up.
 
I would suggest you contact Doug Dutra ('Doctor Dodge') over on the www. slantsix.org forum about some new moderate lift/moderate duration cam grinds that make more torque (and thus mid-range HP) with a 1 BBL or 2 BBL carb. I am about to install a new one for the 1 BBL in a fresh engine rebuild; the 2 BBL version should breathe a bit more at mid to higher RPM's to match up with the better flow of the Super Six. These will work with stock or replacement stock springs (like the VS510's), and stock valve trains.
 
nm9stheham said:
I would suggest you contact Doug Dutra ('Doctor Dodge') over on the www. slantsix.org forum about some new moderate lift/moderate duration cam grinds that make more torque (and thus mid-range HP) with a 1 BBL or 2 BBL carb. I am about to install a new one for the 1 BBL in a fresh engine rebuild; the 2 BBL version should breathe a bit more at mid to higher RPM's to match up with the better flow of the Super Six. These will work with stock or replacement stock springs (like the VS510's), and stock valve trains.
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Just one more comment RE: Long rods...

NHRA's National Dragster had a tech article a few years ago, by David Reher, the engine builder that is half of the Reher/Morrison Pro Stock team. These guys spend their LIFE on the dyno, and I mean engine dyno, not chassis dyno.

In this particular article, David was asked the importance of the rod-ratio thing, in reference to longer rods making more power. His response was clear-cut. He said, unequivocally, and without hesitation, that the connecting rods' sole function, was to connect the piston with the crank-throw... nothing else! He stressed that the old wives' tale about rod-length having any significant effect on power output was just that; an old wives' tale.

To worry about that (rod-length) in a street engine is a complete waste of time, if you give any credence at all, to what one of the top engine builders in the country (for years,) said about it. It was on the back page of a National Dragster a few years back...

Just a word to the wise...:violent1:
 
Bill Dedman said:
the connecting rods' sole function, was to connect the piston with the crank-throw... nothing else! He stressed that the old wives' tale about rod-length having any significant effect on power output was just that; an old wives' tale.
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Now THAT is good to know, for this motor and all others, thanks man!
 
Bill Dedman said:
Just one more comment RE: Long rods...

NHRA's National Dragster had a tech article a few years ago, by David Reher, the engine builder that is half of the Reher/Morrison Pro Stock team. These guys spend their LIFE on the dyno, and I mean engine dyno, not chassis dyno.

In this particular article, David was asked the importance of the rod-ratio thing, in reference to longer rods making more power. His response was clear-cut. He said, unequivocally, and without hesitation, that the connecting rods' sole function, was to connect the piston with the crank-throw... nothing else! He stressed that the old wives' tale about rod-length having any significant effect on power output was just that; an old wives' tale.

To worry about that (rod-length) in a street engine is a complete waste of time, if you give any credence at all, to what one of the top engine builders in the country (for years,) said about it. It was on the back page of a National Dragster a few years back...

Just a word to the wise...:violent1:
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Yup. I actually remember that article. Like they say, you can lead a horse to water and he'll still argue with you. lol
 
In the previous post about Conrods....their sole purpose is to turn Linear Motion into Rotary Motion......but....there is a thing called Rod length to Stroke length Ratio....that is what makes a smooth engine, or a torquey engine, or a revvy engine.
We got a 302 Clevo donk here....the US didn't get them....anyway, they had a 3" stroke, and 4" bore like the 351C....but the 302 rods were 6", and the 351 rods were 5.8".
They would use the 6" rods in a 351, and special pistons....made them develop more torque.....apparently.....to do with dwell time at the ends of the strokes.
 
cjh said:
In the previous post about Conrods....their sole purpose is to turn Linear Motion into Rotary Motion......but....there is a thing called Rod length to Stroke length Ratio....that is what makes a smooth engine, or a torquey engine, or a revvy engine.
We got a 302 Clevo donk here....the US didn't get them....anyway, they had a 3" stroke, and 4" bore like the 351C....but the 302 rods were 6", and the 351 rods were 5.8".
They would use the 6" rods in a 351, and special pistons....made them develop more torque.....apparently.....to do with dwell time at the ends of the strokes.
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David Reher says that is a crock... I tend to listen when he talks... He has no reason to disseminate false information; his credibility is at stake, writing for a vehicle like National Dragster, where most of the readership is engine-literate.

And, you're right; turning linear motion into rotary motion is what rods do, BUT they do it by connecting the piston with the crank...if they didn't do that, they would have no function, right?
 
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