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custom connecting rods may soon be avaible ............
https://slantsix.org/forum/viewtopic.php?t=26519
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Author:  gmader [ Mon Jan 07, 2008 8:11 pm ]
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This gets us really close to what we want. The big end is about the right size, and the small end needs to be bigger to fit the correct piston pin.

With this, we can use 2.2 turbo pistons, with 1.604 compression height. My wild guess is that a piston with a 1.6" compression height is generally lighter than a 1.73" compression height piston, and certainly lighter than stock. There are after market forgings for 2.2 mopar turbo, so we are not starting from scratch, with the cost and complications that go with that. I really want to get replacement pistons easily, if I need them. That again argues for an off the shelf, but forged piston.

Please don't take these observations as criticism. I am willing to jump on board with this, and sell my 198 rods, but meet us half way. Start with a high performance, off the shelf piston, let's design a rod around it, and we all win.

Greg

Author:  Dart270 [ Tue Jan 08, 2008 5:26 am ]
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OK, the "standard" rod size could be 6.9" for those who want to use Slant Six stock dimension pistons. I agree it should trivial for the fabricator to make them in whatever length.

I assume "k1tom" is the fabricator? Thanks for chiming in, if so.

Not trying to be critical, mopardemon71, just throwing ideas around. If you make rods at that price that are good, people should buy them.

Lou

Author:  slantzilla [ Tue Jan 08, 2008 5:55 am ]
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The rotating assembly Mike is getting together for me now is going to use custom forged +.100" over nitrous pistons from Venolia. Since we are using the stock 6.7" rods, Mike is having the pin moved down .120" ish on the piston to get the deck height up w/o decking a ton off the block. Mike sees no issues with running a low pin position.

Custom pistons are only about $60 each. Take that into consideration when deciding on rod length. :D

IIRC, Mike's last set of aluminum rods was in the neighborhood of $700 w/ custom length and Honda journals. Just an FYI on what's out there. :D

Author:  Doc [ Tue Jan 08, 2008 8:56 am ]
Post subject:  Do the Math...

As a benchmark, here are some costs on getting stock SL6 rods ready to install:

We know the 198 rod is a challenge to find but they are out there.
I have paid anywhere from $5 to $35.00 per rod for them, $35.00 usually being NOS (new) or a cleaned and resized connecting rod.

So:
$200 for the rods (set of 6)
$100 for ARP bolts (installed)
$120 to resize (a 'must' with new bolts)
$100 to have them deburred and balanced (optional)

So if you could buy "better" con rods that used available pistons, ready to go, for around $500.00 a set, you would be ahead of the 'game'.

Truth is that I can usually get factory 198 rods ready to go racing for around $300.00 a set and last time I checked, I have never broke one. (knock on wood)
DD

Author:  mopardemon71 [ Tue Jan 08, 2008 6:09 pm ]
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I was going to send off a piston/rod to Tom today but i got hung up at work. Tom is a great guy and he has "connections" at Wiesco and this maybe a simple/sneaky way to have good pistons for the slant made. With the combo in his hands he can tell what is needed and see were I am going for my build. I think everyone is a bit stuck using the 2.2 pistons and sorry Doc I've only found one 198 and #5 rod was poking out of the block and saying "Hi" to me :shock: . All I'm doing I guess is tring to give, to me anyway, an easier option for a engine build. Doc, if you want pm k1Tom and see what he is doing for me and see what you think.

runvs_826, I wont be running bigger than .501 lift on my build but if you did run bigger, the piston can be fluted for valve clearance. If you want a short skrit on you piston then spec it for that. If we start stock and show that the pistons move, they would be more inclined to offer more choices to us. I'd like to think. :D

Author:  runvs_826 [ Tue Jan 08, 2008 6:39 pm ]
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We had some major problems with what I call piston slap. What had happen is my uncles "buddy" put the short block together and I had assembled the heads. Upon fireing up the engine we learned he didn't pay attention to the valve reliefs and the intake valve hit the piston. The moral of the story is measure twice, and than double check sometime later.
I believe the rods should be awesome Mopardemon71, like I said I had tried this earlier, but couldn't find a suitable connection/supplier. I think those who can afford this should be glad about the oppurtunity. Personally you can count me out, the funds aren't on my side this year.
Not to be a naysayer for sixes, but I've found most engines won't need this but could benefit from a balance and polish jobs. That being said, it would be nice to have a semi-aftermarket rotating assembly that you could have as a "bulletproof" bottom end. Since most/some cranks are forged this is kinda the last piece of the puzzle huh?

Author:  slantzilla [ Wed Jan 09, 2008 7:23 am ]
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I have been running a Car Quest reground crank and bearing kit, rods set up like Doug's, and 2.2 turbo pistons for years No balancing, nuttin' fancy. Never had an issue that wasn't nitrous related.

One thing you have to remember about using 2.2 pistons. The valve reliefs in some of the pistons will be backwards to a Slant and not useable without remachining.

Author:  k1tom [ Thu Jan 10, 2008 5:23 pm ]
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Quote:
Are you the rep for the company making the rods? I would disagree for the slant six that moving the piston up somehow up the bore that you could easily run into piston slap. I guess it would depend on how much lift and how far up, just like any engine. But it was a great wake up for my engine!
What do you plan on the design of the pistons? Also what material? I do agree that lighter pistons will help with revs and is one trick to utilize to offest the long stroke.
What do you plan to make the rods out of? Are they billet or forged? I had attempted to get something like this rolling before and many CNC labs wouldn't cut them for "insurance purposes", one even metioned that he couldn't pay for fixing a 100 cars becuase of MY design flaw, I laughed and thanked him for his time.
I am not the rep for the company. I am the President of K1 Technologies and the one who has offered to make the rods. I have been in the racing industry for about 27 years and have been designing connecting rods for that length of time. During this 27 years, I ran one of the largest connecting rod manufacturing companies in the country prior to starting K1 Technologies 3 years ago.

You are correct in the fact that moving the piston up will not cause piston slap. Piston slap comes from the piston rocking in the bore causing the skirt of the piston to slap the cylinder wall. Moving the piston up in the bore can however, cause the piston to make contact with an open valve unless proper clearance is provided.

The rods that we make are made from 4340 steel and are a fully machined billet piece that is heat treated, shot peened and magnafluxed to insure long life. They also have full floating bushed wrist pin ends and come with ARP rod bolts.

The pistons would be Wiseco brand. They are a forged aluminum piece that is much stronger than the cast pistons that come from the factory. They also have an offset wrist pin bore to eliminate piston slap.

Author:  runvs_826 [ Thu Jan 10, 2008 5:31 pm ]
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Sounds good! I would be interested in something like this over the next year or so, but not any time soon. I would warn you a little most slant race guys don't have deep pockets or adopt the more older hot rodding tricks, just to give the business side of you a little bit of heads up. On the other hand you sure don't have a lot of competition!
I read a lot about the piston movement in the bore with could be solved with smaller skirts and better rod ratio. We completely fixed it in my uncles new stroker being as the bore now perfectly aligns it with the rod making the centrifigal movement being performed solely by the bottom end. So the custom rods and pistons will be the last piece along with the forged cranks should be a rock solid bottom end. Hemidup might be interested as he is on the road to build a 10sec car.

Author:  slantzilla [ Fri Jan 11, 2008 5:49 am ]
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Would this be you?

http://www.campbellenterprises.com/index.php

I am sending Mike the money for pistons next week. What kind of price would you have on a set of stock length 6.7" rods? :D

Author:  k1tom [ Sat Jan 12, 2008 2:34 pm ]
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Quote:
Would this be you?

http://www.campbellenterprises.com/index.php

I am sending Mike the money for pistons next week. What kind of price would you have on a set of stock length 6.7" rods? :D

No. Check www.k1technologies.com

Author:  k1tom [ Sat Jan 12, 2008 7:00 pm ]
Post subject: 

Quote:
Sounds good! I would be interested in something like this over the next year or so, but not any time soon. I would warn you a little most slant race guys don't have deep pockets or adopt the more older hot rodding tricks, just to give the business side of you a little bit of heads up. On the other hand you sure don't have a lot of competition!
I read a lot about the piston movement in the bore with could be solved with smaller skirts and better rod ratio. We completely fixed it in my uncles new stroker being as the bore now perfectly aligns it with the rod making the centrifigal movement being performed solely by the bottom end. So the custom rods and pistons will be the last piece along with the forged cranks should be a rock solid bottom end. Hemidup might be interested as he is on the road to build a 10sec car.
We specialize in bringing to market high quality parts at an affordable price. This includes custom and / or custom short run batches of connecting rods. Until we sort out what everyone actually wants, we cannot come up with a solid price but it will be less than the cost of the reconditioned factory rods listed above plus will be made out of a much better material than the factory rods.

Author:  mopardemon71 [ Sat Jan 12, 2008 8:31 pm ]
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Hey Tom, I have sent out the rod/piston and you soud have it on or around tuesday. What do you think I should use to make that combustion chamber profile for the piston with? The wife said plaster but it sounds messy :roll: . Call me when the package gets in please.

Author:  LUCKY13 [ Sun Jan 13, 2008 12:06 am ]
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The 7.1 rod for the big block Mopars with the Chevy rod juarnal is not far off from working as is. This would make for a nice piston package also.



Jess

Author:  k1tom [ Sun Jan 13, 2008 8:26 am ]
Post subject: 

Quote:
The 7.1 rod for the big block Mopars with the Chevy rod juarnal is not far off from working as is. This would make for a nice piston package also.



Jess
Regarding the big block Mopar rod, not only is the offset of the rod beam wrong, the width of the big end is too narrow. Being too narrow will allow the rod to slide around on the crank. This extra side clearance will also cause the rod to run off center in the bore which will upset ring seal plus side load the rod, potentially causing rod failure.

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