SpriceyStuff
Well-Known Member
Hey guys. I was curious if anyone knows about any 198 size rods for a cast crank with the narrower journals? I’m looking to boost compression in my late model slant.
M1 or Kolnar were making them.
Otherwise I've heard of people (never done one myself) surface grinding cast crank 198 rods to cast crank width before.
That's kinda what I figured. Thanks! I know some guys at machine shops around town, so I'll look into some 198 rods at some point before I go to throw my motor together and see how much they'll charge me to grind on em a bitThe pin end is the same width on both the cast and steel crank rods.
Narrowing the big end of the connecting rods is not difficult, but it is machine shop work. Maintaining the specified rod side play on the big end is important. One would also need to re cut in the lock slots.
To keep the rod properly centered, the same amount would need to be cut from each side.
No, he barely or sometimes not at all pronounced the "h" so it's "Just one more ting" lolAs Colombo would say,
‘Just one more thing’
ARP has different part numbers for the slant six cast and steel crank rod big end bolts.
How they are different and how that would play into narrowing a set of steel crank rods, if at all, I don’t know.
I would place a call to Molar/K1 first, the cost to acquire, machine, notch, add ARPs, & re-size is going to rival a new set of rods easily.That's kinda what I figured. Thanks! I know some guys at machine shops around town, so I'll look into some 198 rods at some point before I go to throw my motor together and see how much they'll charge me to grind on em a bit
Yes, you quickly will be approaching the cost of aftermarket rods. Plus, don't forget after narrowing them, they'll have to be re-chamfered on both sides in the big end. So all those things almost make it cost prohibitive because you still end up with an inferior rod for the same cost or more than an H-beam rod.I would place a call to Molar/K1 first, the cost to acquire, machine, notch, add ARPs, & re-size is going to rival a new set of rods easily.
Hey guys. I was curious if anyone knows about any 198 size rods for a cast crank with the narrower journals? I’m looking to boost compression in my late model slant.
That makes the assumption that K1/Molinar will do a run of cast crank long rods, as that is what this post was about initiallyYes, you quickly will be approaching the cost of aftermarket rods. Plus, don't forget after narrowing them, they'll have to be re-chamfered on both sides in the big end. So all those things almost make it cost prohibitive because you still end up with an inferior rod for the same cost or more than an H-beam rod.
He has made short runs of long rods for the Ford and Chevy 6 cylinder guys before when approached about a "group buy", so its possible he would do the same again for the Slant since he's made them before, and he already has drawings and tooling to do it with....That makes the assumption that K1/Molinar will do a run of cast crank long rods, as that is what this post was about initially
Supposedly the KB268 pistons work, and they have pin lock grooves. Only problem is they're sold in sets of 4 so you need to buy 2 sets to get 6 pistons, and they're about $285/set. Campbell Enterprises sells a set of Wiseco pistons with rings for about $500, but they're flat tops so you end up with a little over 10:1 compression ratio. The KB's give a little over 9:1 iirc.IIRC stock pistons have the pins at the wrong height to use 198 rods. So pistons go on the shopping list. Used to be 2.2 turbo ones?
I thought about swapping a 225 crank into my 198 at one time. Bad idea with the existing pistons.
Sounds very cool!I may end up buying the van next door. My buddy sold it to the neighbor. 1980 I believe. Solid lifter, peanut head, cast crank(?) 8.25 double tag rear end. 3:55's with a sure grip. I did what I call an RV port job on it. Rebuilt a super 6 BBD and pulled the 1bbl off and did the electro crap intake. It has the 833OD!
They are made from the same blanks as the forged rod Slants, so it wouldn't be any trouble for him to make them....I spoke with Tom Molnar last week and he seemed open for another run of rods. He just needs enough interest. I THINK he said five sets would do it. My memory is terrible. He seemed particularly interested in my long rod closed chamber head build though. Said he really likes the slant 6.
Right, but the big end is pretty different. And it's not just a case of grinding the big end down to the .940 width, because the rod bearing tang is in a different location, so they have to make ah whole new rod. dangit all.They are made from the same blanks as the forged rod Slants, so it wouldn't be any trouble for him to make them....
Now keep this in mind. A lot of people don't know this. There are TWO distinctly different slant 6 cast crankshafts. There's a light one and a heavy one. Pretty easy to tell apart, because the counterweights are a good bit smaller on the light cranks.I may end up buying the van next door. My buddy sold it to the neighbor. 1980 I believe. Solid lifter, peanut head, cast crank(?) 8.25 double tag rear end. 3:55's with a sure grip. I did what I call an RV port job on it. Rebuilt a super 6 BBD and pulled the 1bbl off and did the electro crap intake. It has the 833OD!
Post this over at .org it is likely that a couple of folks over there would be interested in a set of cast crank long rods. That would help get the order numbers up.I spoke with Tom Molnar last week and he seemed open for another run of rods. He just needs enough interest. I THINK he said five sets would do it. My memory is terrible. He seemed particularly interested in my long rod closed chamber head build though. Said he really likes the slant 6.