Rod alignment

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groberts101
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Re: Rod alignment

Post by groberts101 »

digger wrote: Fri Mar 23, 2018 6:42 pm So if the non offset rod is in the middle and you used a offset rod then it would no longer be in the middle. So we also have offsets rods also being in the middle and thus with non offset rod they would not be in the middle anymore presumably due to the particular crank?

In that case if you had a crank that needed an offset rod to sit in the middle what's wrong with using it? It seems pretty reasonable to want to minimise secondary motions of the piston by havering the rod nominally in the middle even though it moved around a bit it's limited to being in the middle on average
No way could it be the crank or the block unless either was made to non-oem geometry. Custom journal widths and/or bore spacing. Probably should just keep my big nose out of all this but can only guess it has more to do with bastardized engine parts combos where corrections need to be made. Which still makes not much sense when custom rods would fit that kind of custom crank build anyways.

I do know that simply narrowing the wider oem architecture chevy rod to fit the ford cranks reorients things back towards what has been shown to be a more centralized location on the pin anyways.
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Re: Rod alignment

Post by groberts101 »

blykins wrote: Fri Mar 23, 2018 6:54 pm
groberts101 wrote: Fri Mar 23, 2018 6:39 pm Got curious and just looked at my scat rodded/eagle cranked Windsor block. Molner must think I was born yesterday too cause I don't need no stinkin' centric rod design on mine either. Must be a Chevy thing. Lol

Edit.. i guess it IS a Chevy thing! Wanted to use a Chevy 6" rod in this little 8.2" block.. so glad I didn't but at least I now know Molner will straighten me out if I go that route in the future. :lol:
I used a Molnar 5.700 Chevy rod on a 289 ford road race engine. No issues. :-)

Did you narrow the wider chevy rods to fit the much narrower Ford crank pin?.. or just chopped the hell out of the crank to squash them thar Chevy parts back in there?
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Re: Rod alignment

Post by Steve.k »

Thats right the chevy rods are wider so they have to be narrowed. You must be telling them your application and they are cutting to ford offset. Also some have tried bbc on 400 ford. But theres a huge discrepancy there. The big chevy is way wider. So unless they are cutting either the rods and crank to fit it will not work.
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Re: Rod alignment

Post by blykins »

groberts101 wrote: Fri Mar 23, 2018 7:04 pm
blykins wrote: Fri Mar 23, 2018 6:54 pm
groberts101 wrote: Fri Mar 23, 2018 6:39 pm Got curious and just looked at my scat rodded/eagle cranked Windsor block. Molner must think I was born yesterday too cause I don't need no stinkin' centric rod design on mine either. Must be a Chevy thing. Lol

Edit.. i guess it IS a Chevy thing! Wanted to use a Chevy 6" rod in this little 8.2" block.. so glad I didn't but at least I now know Molner will straighten me out if I go that route in the future. :lol:
I used a Molnar 5.700 Chevy rod on a 289 ford road race engine. No issues. :-)

Did you narrow the wider chevy rods to fit the much narrower Ford crank pin?.. or just chopped the hell out of the crank to squash them thar Chevy parts back in there?
Narrowed the rods and used a Chevy v6 bearing.
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Re: Rod alignment

Post by Steve.k »

Ahh narrowed the rods to ford.why not just order ford spec(centra lign) and not mess with piss all??Be more reasonable and easy to keep track of bearings!
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Re: Rod alignment

Post by elwood »

been arguing BS the whole time

who's winning in your head?
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Re: Rod alignment

Post by blykins »

Steve.k wrote: Fri Mar 23, 2018 8:01 pm Ahh narrowed the rods to ford.why not just order ford spec(centra lign) and not mess with piss all??Be more reasonable and easy to keep track of bearings!
Keep up with the conversation, man.

They don’t have a 5.700” rod length in a “Centralign” rod.

I didn’t have trouble with keeping track of bearings, and it wasn’t anymore difficult to do it this way than any other way. Molnar narrowed the rods for me and cut the tangs in the big end. It’s not as big of a deal as you would make it out to be....and neither is changing a Ford crank to a Chevy rod journal.

Anything else you guys want to try and start a witch hunt about?
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Re: Rod alignment

Post by groberts101 »

blykins wrote: Fri Mar 23, 2018 7:47 pm
groberts101 wrote: Fri Mar 23, 2018 7:04 pm
blykins wrote: Fri Mar 23, 2018 6:54 pm

I used a Molnar 5.700 Chevy rod on a 289 ford road race engine. No issues. :-)

Did you narrow the wider chevy rods to fit the much narrower Ford crank pin?.. or just chopped the hell out of the crank to squash them thar Chevy parts back in there?
Narrowed the rods and used a Chevy v6 bearing.

Thanks.. kinda what I figured. Btw.. that 6" rod in the 8.2" block was just playin to see if everyone was paying attention. :D
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Re: Rod alignment

Post by cjperformance »

Look at centralines pic of the 'typical ford stroker rod' and their offset rod. Big end flange on the typical rod is centered, now who buys a ford 'stroker rod' with a centered big end flange!!?? Have a look at the big end flanges on all the pics with centered rods, each one has an offset big end flange as does any correct ford stroker rod! I have seen stroker kits with incorrect offset on the big end flange but thats because its 'incorrect' simply the correct stroker rod has everything in the right place. Personally i dont see any need for the centralign if you are buying all the correct parts in the 1st place!
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Re: Rod alignment

Post by bobalattie »

Why can’t ya all agree that there is on set answer to what is gonna work all the time? Sometimes depending on who makes the crank and rods, it isn’t all gonna align perfectly? If I had the funds to buy a aftermarket block that would accept 2.75” mains, then my choice of crank shafts would have been much greater than using an oem block with 3” mains, there for I was stuck using either scat or eagle for a neutral balance crank shaft. And with that I needed a set of 2.100 Chevy rods and the molnar rods happen to align perfectly in this case.. had I had the opportunity to buy a Callie’s or crower, or whomever’s crank shaft, then maybe they wouldn’t have aligned as well as they did..

Point being, not everyone has big $$$ to buy the best parts, scat and eagle sell a lot of cranks to a lot of budget minded enthusiast.. and in those instances the molnar rods seem to align well, if they don’t, then they should return them and but then standard sbc rods and see if they align correctly..

Seriously, this was supposed to be a discussion about what’s available for the consumer and what may be the best approach to building a sbf given the circumstances..
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Re: Rod alignment

Post by blykins »

Bob, not to perpetuate this train wreck thread, but the Scat stuff usually gives me good results as well.

I don't think it makes a hill of beans difference whether it's centered or not. I've even seen factory Ford FE stuff be off-center. The only way you're going to make it perfectly centered, even when the engine is running, is with a piston guided rod and a thin big end so that it has room to move without creating friction.
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Re: Rod alignment

Post by Steve.k »

Well i just looked up all scat rods and every chebby rod other than a ibeam is bigger than ford. So in order to fit they have to be narrowed. More cost. If you use a chevy style crank the offset would be off. Brent you must be giving the usage and they cutting to fit for you.
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Re: Rod alignment

Post by blykins »

Steve.k wrote: Sat Mar 24, 2018 11:07 am Well i just looked up all scat rods and every chebby rod other than a ibeam is bigger than ford. So in order to fit they have to be narrowed. More cost. If you use a chevy style crank the offset would be off. Brent you must be giving the usage and they cutting to fit for you.
Steve....

They fit the ford Scat/lunatics/callies/eagle cranks with sbc rod journals just fine. And that’s what this thread is about. Stop making this harder than what it is.

When you use a Chevy rod on a ford rod journal, of course the rod journals have to be modified! But I have access to excellent crank grinders. Plus, a smaller journal and bearing along with a myriad of rod length choices is always a better route.

Every pic I have posted have been off the shelf cranks with no tweaking and off the shelf rods with no tweaking. That’s how easy it works.

The 289 deal was a completely custom engine and the combination I wanted isn’t available off the shelf.
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Re: Rod alignment

Post by Steve.k »

Ok yes im making it harder? You can buy a system thats already to go or buy the chevy stuff abd retro fit! Seems like a no brainer. But hey you do want u like.I dont have a problem buying there stuff.
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Re: Rod alignment

Post by blykins »

Are we onto another argument about buying off the shelf stuff vs custom for custom race engines now??? Rofl. You crack me up man.

Listen, this thread is not about custom parts in custom race engines. It’s about the centralign stuff being a gimmick.

Every picture I posted in this thread was all off the shelf parts that you don’t have to modify at all. A kit, ready to go, that works perfect.

Anything else you want to argue about to take the focus off the centralign stuff? Oil pans? Vacuum pumps?
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