Re: GMForged Rods on Turned 401 Cranks

["Todd Wallis" <cyclone@xxxxxxxxxxxxx>]

Randy,

I got the impression  from your post that you are in Texas.  Which city?

Todd Wallis
Austin, TX


----- Original Message ----- 
From: "Guynn" <amx69@xxxxxxxxxx>
To: <hh7x@xxxxxxxxxxx>; <mail@xxxxxxxxxxxx>
Sent: Saturday, January 29, 2005 10:28 PM
Subject: Re: GMForged Rods on Turned 401 Cranks


> Brien, Lynn,
> I must agree with everything Lynn said, but I will also add to what he 
> said.[my opinion, yours may vary]
>
> Well  you can certainly turn amc 401 cranks [any of then, 290 thru 401] 
> down to different Chevy sizes and you can run cheaper aftermarket rods, 
> AHEM.... To some extent. It is not always that cut and dried.
>
> The 401 crank has 2.249 rod journals. Bigger than a BB Chevy. [in fact 
> you can use BB rods on AMC] However, when you turn ANY , not just AMC, 
> Steel crank much past .020, you have efectively turned off all the 
> surface hardening of the crank. You are down to SOFT Forged steel, not 
> Heat Treated surface.
>
> So, if you want to run a set of Chevy rods, and have your stuff live, 
> yoyou will need to spend money on Crank Prep Work. Follow along for the 
> needed work. , On a normal crank turn job, the crank grinders, both 
> machine & man running it, they turn down and polish an average of  .015 
> off the cranks. Most less than .010, some out to .020, a few out to 
> .030. But very, very seldom do they remove .149  the amount needed to 
> get even the 2.1 big journal Chevy rod on. The grinder runs longer, eats 
> the wheel quicker, the crank work costs more. And, after you pop off 
> that .149, you need to get the journals surface treated, PROPERLY. 
> Unless you got a free crank grinder and crank heat treat equipment, you 
> can expect to spend about $400.00[2 years ago] around here [Texas] to 
> get the work done. I know  machine shop prices are almost double that in 
> some areas.
>
> Offset grinding can be done when you turn the crank to Chevy size as 
> well. Same deal, you need to re-treat the journals. Some shops charge 
> about the same to Offset grind as a Straight grind on that big a cut.
>
> Now to Cheap Forged Rods. #1, You get what you pay for EVERY TIME.
>
> The Good Chinese rods start in price at about $349.00 These would be 
> comparable to thje SCAT pieces that some thought were too high at $379, 
> then $399, then $450, And now I am told $650???? Scat as example sells a 
> cheaper I beam rod as well. But they get so cheap that the low ball ones 
> you can get for less than $200.00 a set, while the ''grading'' of the I 
> beams goes up in about  $269.00 Some other Import rods I have seen on 
> Close Outs at $149.00 a set.
>
> So, you get the cheapest junk rods and put on your just done crank, and 
> one lunches out on you, WAS IT SAVING A LOAD OF MONEY ON RODS?>?????? If 
> you  must spend extra money on the crank in order to run even the Better 
> rods, not cheapos, is that really better than just running the same old 
> Forged rods that cames in the 401 to begin with???
>
> A ""CLAIMER'' motor is one built to win the race, with the CHEAPEST 
> parts you can buy, because someone else you are racing can CLAIM your 
> engine for $1500.00 if you win and they pput up the money. This is what 
> the El Cheapo import rods are made for, not to use on a everyday drive 
> around vehicle, much less a Hot Rod, the person is 'INTENDING I Hope''to 
> build and drive And hammer on a fewYEARS.
>
> In my Opinion, If you Want or Need to build Throw Away engines then buy 
> throw away parts. If you want to build something to lastr over the long 
> haul, buy the better parts..Pretty basic, Quality parts and labor costs 
> more than cheap parts and labor. But in the long haul the quality way is 
> much better.
> CHEAP also comes into play with labor. If you are shopping machine shops 
> for the lowest prices, you are just asking for engine machining 
> troubles. You shop for a Machine shop by learning if the are competent. 
> Once you have found a Good Shop with Good personel, PAY THE PRICE, it is 
> much mi, much cheaper than re-doing what gets ruined by the Cheap shop.
>
> If you get an AMC crank ground for Chevy rods, and the person grinding 
> the crank does not watch the Journal Radius, you could very well cause a 
> bearing seasure, and, if you Cheap out and don't re-treat the journals, 
> you will have scrap metal in a short while.
> So, Yes, you can indeed Turn AMC cranks and put on cheap Chevy rods. Do 
> you save a Load of money?? Not really.
>
> Regards, Randy Guynn