Crower or Pauter rods?

[GeneSplicer]

My Crower rods have been on backorder for several weeks and I have been toying with cancelling the order and wait on some Pauter rods. Would any of you go one or the other way? Why/why not? They're the same cost at around $1100 so if one gives a discinct advantage I'd like to know... gotta hold up to 800+

[IJ.]

Some things never change!

A few years ago I was faced with this exact situation and went for the Pauter's and had 0 regrets.

[Doward]

Same price, I'd take Pauters over Crower.

Nothing against Crower, the Pauters are just that good!

[Moy]

Some things never change!

A few years ago I was faced with this exact situation and went for the Pauter's and had 0 regrets.

Ian, how much of the block had to be ground away to clearance the rods?

[IJ.]

Ian, how much of the block had to be ground away to clearance the rods?

About this much on a stock bore 7M ;)

http://ij.supramania.com/assembly00.jpg

[Mk3runner]

damn, thats not a whole lot at all.

[IJ.]

If it's going to be revved over 8k the Oil pump shaft needs to be relieved in 2 places by 2mm as well.

[Mk3runner]

If it's going to be revved over 8k the Oil pump shaft needs to be relieved in 2 places by 2mm as well.

why?

I'm curious to this.

[IJ.]

With the amount of flex/wobble in a 7M at those engine speeds the rods touch the shaft.

[Mk3runner]

wow!

never would have figured.

[IJ.]

Yep mine had a couple of mm clearence and still managed to brush the shaft and chatter the bearings, quick cut in the Lathe and all was well.

Big long wet noodle engines move around a LOT more than you'd expect (part of why I'm not keen on solid engine mounts)

[Mk3runner]

solid mount seems way too harsh anyways.

I knew motors at that range of speed could cause interference but to this extent, its just wow. makes me wanna dig up your old build and read for days.

[IJ.]

I was a bit stunned that it could flex that much as there's plenty of clearence to the shaft :aigo:

Had to swap out the 7M crank as it had chattered #1 and #2 crankpins enough to be visible, turned the shaft fitted my spare identical prepped 6M crank and all was well again.

[Mk3runner]

so your saying that the older less balanced 6m crank out performed the heavier 7m? I would suppose so giving it revs out higher...

[IJ.]

No not saying that at all, both cranks had the same balance and identical prep work it's just that the 7M was marked up and I had the fresh 6M one there.

I was interested to see if there were any differences with just the crank swap, the Oil Pump drive shaft issue was corrected by turning it down 2mm.

As a direct comparison the 6M was harsher until 6500 but did accelerate quicker then it was impossible to tell any difference as the 7M gets busy from there to my 8500 limit, all of this inspired me to remove the same amount of weight from the 7M crank and put it back in so I had the best of both worlds.

http://ij.supramania.com/crank01.jpg

http://ij.supramania.com/crank02.jpg

http://ij.supramania.com/crank03.jpg

[Mk3runner]

ahh, I see. I misread.

this is interesting.

[IJ.]

While it's a bit of a threadjack I hope it's useful info for the OP ;)

[GeneSplicer]

Naw guys, that's cool... I learned something! So if I do go with the Pauters then there's a little rod clearance issue... no big deal to do while it's in the shop... if the Pauters are super better than Crowers... I kinda placed them in the same league.

That's interesting info on the oil pump shaft... and an easy fix too. Thanks for the heads up.

[IJ.]

Very welcome Gene

[mk3ukr]

About this much on a stock bore 7M ;)

http://ij.supramania.com/assembly00.jpg

Ian, what is the closest distance between the rod beam and bottom of the cylinder after grinding?
After thinking about 7M as long twisting noodle it should be at least ~2 mm?

[IJ.]

Can't remember exactly but yes around the 2mm mark.

[Mk3runner]

This thread is very informative, a few things to keep in mind when I go tear the engine down again.

[gofastgeorge]

That's funny - 'Big long wet noodle engines'.

The Pauter rods are looking like the way I may go.
The clearance at the base of the cylinder will be less of a problem, since I am going with a 85mm bore.
The pump shaft may not be an issue, since I am considering a dry sump system.

[Mk3runner]

dry pump would be cool!

[mk3ukr]

I never heard any bad word about Pauter, here is my experience with these rods. First of all - when Rich (Suprarich) measured them big end bores were all over (random sizes :) ) He resized all rods and shipped set to me. Today I got call from machinist who is working on my short block. I went to his workshop and he measured in front of me my CP piston pins - perfect 22.000 mm, within Toyota specs. Then he measured small end bushing ID - it was hugely oversized, oil clearance 0.05 mm, 5 times higher then specs. And most interesting - some bushings got 0.02mm ovality, unbelievable.

[IJ.]

I never heard any bad word about Pauter, here is my experience with these rods. First of all - when Rich (Suprarich) measured them big end bores were all over (random sizes :) ) He resized all rods and shipped set to me. Today I got call from machinist who is working on my short block. I went to his workshop and he measured in front of me my CP piston pins - perfect 22.000 mm, within Toyota specs. Then he measured small end bushing ID - it was hugely oversized, oil clearance 0.05 mm, 5 times higher then specs. And most interesting - some bushings got 0.02mm ovality, unbelievable.

Wow I'm shocked all of mine were 100% perfect!

[mk3ukr]

Shit happens sometimes, why it happened to me :aigo:
Ian, they didn't measure yet rod side clearances, I hope they are not too loose, remember yours were too tight.

[figgie]

<== another happy as can be custom pauter rods owner. :)

[Spade]

Thanks for the heads us on the shaft clearance issue!

[Adjuster]

I have Pauter rods, and they have been robust to say the least. The customer service is excellent too compared to any other supplier I've worked with. (They actually listened to me, gave good advice, and then did what they said they would do in a reasonable amount of time.)

My block has more material removed than Ian's due to the stroker crank, but not as much as you'd expect, since my rod journals are only 2" v/s stock Toyota sized, that are larger than 2" OD. The smaller diameter rod journals make the rods more compact, but they still hit the bottem of the bores with the shoulder beam of the rod.

Also, as Ian points out, cutting down the oil pump drive shaft needs to be done. My first build, it cleared, and we never thought it would hit, but it did, and the impact pushed the oil pump shaft around enough to ruin it.

On my setup, I not only had to cut it down slightly, but also cut the "cutouts" wider, as the Pauter rods are wider at that point than the stock design. Toyota knows this engine flexes, that's why they cut out the oil pump drive shaft like they did.

Last is a machine work, assembly tip, especially if you are doing any coatings.

Do all your machine work, including the clearance work prior to doing any coatings. (Unles you are going to use a old piston for the mock up work.) Sharp edges while doing this will screw up the skirt coatings very quickly. The upside is I noticed things I might not have, but the down side is I ended up coating my skirts twice.

Point of advice. I used a large mill to machine the cutouts. Never thought it would result in a very large, and sharp edge into the bore, untill the piston was pulled down across it, cutting the skirts.

After you cut the clearance, take a stone, or emery paper wrapped around a dowl, and remove any sharp edges along the bottem of the bore. After pulling my piston, seeing the scratches, I flipped the block over, pulled the crank, and felt down to find the ridges.. promptly cutting my finger in the process. It was sharp, and it was larger than I expected! 20 min of work with a stone and sand paper around a stick, and it was fine.

Save yourself the blood, and expense. :)

Go with Pauter rods, they are excellent, and do the machine work, it's worth it to know the rods are the last thing that will fail on your motor.