I called Hughes about those rods. They are prepped 6 cylinder Chevy rods that were done 15 years ago to go into a big block Chrysler so they are too narrow for us on the big end.

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Joshua

Joshie225

How wide of a rod do we need? I was thinking it was like 1.015 but without going back to check the specs i am not sure. So they must be smaller than this. I wander why they list them for the slant six then. Some of the rods setup for Chevy size jurnals on a big block mopar are wide enough though.


I found these but you would have to do something about the rod bearing to get it correct.

http://www.campbellenterprises.com/part ... h7100aprba

I believe they are 1.017 wide and have a .990 pin size with a 2.200 bearing size. the slant is 2.187 on the bearing if that is right so you would have to order a .013 under Chevy bearing or use a .020 underbearing and turn the slant crank .007.


I believe all this add up correct but would like for someone else conferm it. The 1.017 width is only .002 wider than needed (if I am right about the width) and could be dealt with & the piston pin size would have to be considered so you would have to have pistons made but I believe they will work & at a good price also.

It is what I plan on trying to use but I will dig into it more to be sure when the time comes, unless I go for a even stronger rod & then I would just have a set made up but that is very pricy.

So whats your thoughts on these rods?



Jess

Jess,

Hughes had those rods mis-labeled on their web site. They are not for a slant. They were going to be used in a big block.

Big block Mopar rods are still too narrow for a slant. When I get home I'll measure the journal width of my spare crank. It's around 1.200" if memory serves.

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Joshua

I've heard from numerous sources that while the cast crank is weaker than the forged crank, it's still pretty darn strong. I cannot, however, confirm this myself. How many stories are out there of people breaking cast cranks with high performance builds? Since the cast crank has significantly narrower rod journals, would it serve as a more versatile base for a build w/ non-stock rods?

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Used to own:
'82 Dodge D150
Erson 270 Cam, O/S valves, mild port work, ~9.5:1 compression

Currently fighting with an '85 VW Cabriolet

My other passion

Maybe the info I got was wrong on the width. But I went back & looked & I show 1.015 as the width of the rod & I believe I got it from the site or one of the news letters, but I may be mistaken on where the info came from. But it doesnt matter, what matters is finding out the true width. Until I take my motor apart I wouldnt be buying any rods anyways but it still would be good to know for having them lined up when the time comes. Maybe it is the cast crank spec for rod width that I had gotten thinking it was the fordged crank specs.

Yea I just looked at hughs & they have them rods listed differently now.

So I guess we need to know for sure how wide these slant rods really are. If they are wider than 1.015 I havnt seen any rods this wide anywhere which would leave getting 198 rods or having a set made up. Having a set made up would hurt, Cunningham Rods priced me $1200.00 for a set & said it would take about 6 weeks to get them. But they also are Billet rods with stronger bolts than any of the ARP bolts I have seen so I guess they would be worth the price but still hard to justify.


Jess

I've got a set of 170, 198 and 225 rods and they're all right at about 1.205" wide at the big end. Anyone know the width of the cast crank rods?

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Franklin
'61 Valiant

That is not good news Heckshemi. That means custom Pricy rods if you wish to have something better than the stock rod. Atleast I have not found any that is at this width off the shelf, but I had not been looking either for this size. Although I did find a place that said they had 198 rods but I was wanting a stronger rod for my build. I guess it will just cost more, but I will have the option of lenth & pin size if going this route. But at 1.205 that leaves way to much side clearance with a 1.015 rod and will lose oil pressure & have to much windage from oil slinging and side movement of the rod.


Jess

How much torque and HP are you planning for?
My understanding is the weak point if there is one would be the piston.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

Stock rods will live a lot longer than most people think.

As far as the cast crankers go, the first Slant door car in the 10's had a cast crank motor in it.

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Official Cookie and Mater Tormentor.

slantzilla, you mentioned in another post that you can rev a 225 forged crank way more high than stock 198 rods would hold... how far is that? 6k rpm would be safe or pushing them rods over the edge?

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Juan Ignacio Caino

Please use e-mail button istead of PM'ing. I do log in sometimes but I'll be answering quicker thru e-mail.

As far as horsepower & torque go I do plan to push for some very high levels. Much higher than the average build is for sure. But we well leave it at that for now.

I am sure our forged cranks are strong & even the cast cranks may pull off more than one would expect. Mopar has always had some of the best engine parts of anything I have ever built & I have built & raced the Big Blocks on cast cranks with NOS to some very high levels. And I have never run anything more than the factory forged cranks in them & have never had a failure.

But there has been a few cranks break in the Slant Six ( I think even forged ones) And the rod being stronger is not always the only goal, weight can be a important part of the build & the lighter the rod & piston the less stress on the crank & the more power that can be made.

And on my build I probably will run a set of good rods even if they do have to be custom made. And maybe even send the crank off to get it froozen.

I did find the artical that listed the width as being 1.015 & the cast crank was much smaller in width than this . But after reading alittle closer it also says it is The Rod bearing width that is this size & not the rod itself. Although it didnt say what width the rod was or say that it was wider than this or if this was really the size of the rod. It gave main & rod journal diametor & main & rod bearing widths. I would assume that if the bearing itself is 1.015 then the rod probably is what Heckshemi has quoted without a doute (he does have three sets that check all the same). The rod most of the time is wider than the bearing. But without having my engine apart at the moment I dont really know for sure what width it really is. But it appears I misunderstood the artical for what it was saying as far as width of the rod when it may have been meaning the width of the bearing itself. In which case is not good news for finding a off the shelf rod to fit for sure.


Jess

6200 is safe, 6500 is flirting with disaster.

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Official Cookie and Mater Tormentor.

OK then I'm safe and I'll be safe using my 6000 cookie on the MSD
thanks

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Juan Ignacio Caino

Please use e-mail button istead of PM'ing. I do log in sometimes but I'll be answering quicker thru e-mail.

Make sure you setup the MSD for 6cyl operation not 8cyl (or you'll have a 8000rpm cutoff).......................

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Is that what 6=8 means?