Hi-perf Rod's suitable for 24mm WBX wrist pin

Post by **Piledriver** » Thu Apr 26, 2007 12:50 am

Mine are at the machinist.(on hold ATM)

There is TONS of meat on the small end.

Mine may end up 1mm longer, depending on the measured deck of the AA 95.5mm pistons I ordered.

Anyone have any info/specs on the QSC 96mm setup?
LOOK decent enough...

They advertise them as 2.4l, but the pin doesn't look set up high enough for an 84mm stroke...

Unkl Ian · Post by **Unkl Ian** » Sun May 20, 2007 8:14 pm

How does the outside on the big end compare
between the WBX and Uni-tech rods ?

Thinking in terms of cam clearance on stroker motors.

Post by **Piledriver** » Sun May 20, 2007 8:51 pm

They don't compare at all...

The Unitech+ HD rods are clearanced for strokers and are made from 4140 CrMo steel.

They have 3/8" ARP cap bolts, no nuts, bolts screw into the caps like H-Beams. I can pull one apart and see if they use hollow dowels or pins for locating the cap... (Cam's coming tomorrow, I'll be using them next week hopefully)

They are forged and (perhaps...) machined in China.
(They DID check out perfect and within a gram, still need to check them end-to-end, haven't made the jig yet)

The WBX rods... are none of the above, for better or worse.

If I had the stock rods rebuilt by a decent shop and installed the std ARP bolts, the cost would have been ~ the same as buying the Unitechs and having the small end resized/rebushed... give or take $10.

I could have had them offset the bushing ~1mm longer if I had known the deck height issues of the aftermarket pistons in time. (Having my AMC heads flycut to get rid of the step to set deck, matching cut on the water jacket surface +.020 per Type5Joe, less crush)

Under 7000 RPM I'd use the Unitech+ in a heartbeat, esp on a turbo/NO2 motor.. Likely stronger than H-beams in that app.

The small end still has almost as much meat around it as a WBX rod after being resized/rebushed for 24mm pin. (not... disturbingly thin like the 24mm pinned H-beams)

(I really have to find those batteries for the camera...They look sweet)

I bought/modded them as an experiment, as Boston Bob wrote that the stock WBX rods big ends oval out/stretch on the 76 stroke... The logic is that hopefully the better steel and 3/8" ARP bolts will counter that

(and the metal I've seen transferred from the back of the bearing to the rods on the ones I've seen confirm that bearings walk in the stock rods >100K miles)

Unkl Ian · Post by **Unkl Ian** » Sun May 20, 2007 9:11 pm

As much as I hate to use Chinese parts,I'm thinking the Uni-Tech rods
would be good candidates to use with the .927" pin.

The other alternatives require lots of reworking,
resizing both ends plus new bolts,
or don't have enough material for the larger pin.

Post by **Piledriver** » Sun May 20, 2007 9:43 pm

Unkl Ian wrote:As much as I hate to use Chinese parts,I'm thinking the Uni-Tech rods
would be good candidates to use with the .927" pin.

The other alternatives require lots of reworking,
resizing both ends plus new bolts,
or don't have enough material for the larger pin.

I think the Chinese at least have the whole forging steel thing down pretty good... Everyone and their dog uses the forgings, even if they machine them in-house sometimes.

.927 would be no issues, might even get away reaming std bushing... (Didn't measure it)

.945 left tons of meat using a BBC bushing, and CB sells Clevite77 tri-metal T1 rod bearings...

Post by **Piledriver** » Sun Jun 10, 2007 3:21 pm

marcotheturbosteamengine wrote:
Piledriver wrote:
The stock rods are a known weak part on the WBX, the big ends go out of round at high mileage on stock motors.. The 1010 forging (IIRC) doesn't cut it.
...............
The stock wbx rods are not week, the big end goes out of round when the stock cranked engine is over reved(flexing), or it has oil starvation(week oil pump/preasure)and spins a barring, or the bolts streched(2.1 rods over reving again)
most of the time the poor wbx is beaten up all its life with no servicing, and people blame the "week"rods!
i would love to see 100,000mile unitech rod in a wasser after the abuse the common brick layer gives it, you would probaly see it hanging out of the block in 20,000miles

OK Marco, I have another possible use for the WBX rods. What HP and RPM would you consider a safe limit? Will have ARP2000 waveloks, shot peened perfect balance end to end etc, 24mm pin, 532g Cosworth slugs (weight with 24mm tapered pins), 71 stroke. Cam is a 119 on 112 centers, ceramic hybrid lifters.

They LOOK like stock T1 rods as far as all the cross sections, but I can't compare a set ATM.
Stock T1 rods are generally considered to be limited to 150HP and 7K, well prepped, and I would be pissed if the motor I'm working up couldn't ~ double that HP with the stock 2.0 Porsche heads (~180 CFM intakes)

Are the wasser rods a better alloy? Are they slightly beefier in some non-obvious way I'm not seeing? Even Jake mentioned he uses them in some combos...

Considering them for my T4 build on a T1-journal T4 crank.

D Clymer · Post by **D Clymer** » Sun Jul 15, 2007 8:00 pm

Piledriver,

Did you end up buying your Unitech+ rods from CB Performance or from the vendor on e-Bay? CB is out or stock currently and the e-Bay ones are priced right. I just don't want to end up with rods with thin small ends so I want to make sure they are the same as the Unitechs.

Thanks,

David

Post by **Piledriver** » Sun Jul 15, 2007 8:20 pm

I bought them from "racingmanchen" on ebay, obviously the same rods.(Down to the almost-but-not-quite ground off CB logo in the forging)

Another source appears to be from DRD for a few dollars more, supposedly BE machined in-house and balanced end-to-end. Might do the 24mm bushing for you for additional $$.

Getting the small end rebushed locally cost more than it should have, I think my machinist ended up using BBC bushings.

They did come out very nice, bought a set of rockers from the same fellow on ebay, look very nice, but the shipping is brutal, and he does NOT like to combine shipping, so get that straight with him first.

marcotheturbosteamengine · Mon Jul 16, 2007 1:43 am

Piledriver wrote:

OK Marco, I have another possible use for the WBX rods. What HP and RPM would you consider a safe limit? Will have ARP2000 waveloks, shot peened perfect balance end to end etc, 24mm pin, 532g Cosworth slugs (weight with 24mm tapered pins), 71 stroke. Cam is a 119 on 112 centers, ceramic hybrid lifters.

They LOOK like stock T1 rods as far as all the cross sections, but I can't compare a set ATM.
Stock T1 rods are generally considered to be limited to 150HP and 7K, well prepped, and I would be pissed if the motor I'm working up couldn't ~ double that HP with the stock 2.0 Porsche heads (~180 CFM intakes)

Are the wasser rods a better alloy? Are they slightly beefier in some non-obvious way I'm not seeing? Even Jake mentioned he uses them in some combos...

Considering them for my T4 build on a T1-journal T4 crank.[/quote]

turbo or NA? big differance!

Post by **Piledriver** » Mon Jul 16, 2007 6:02 am

Turbo, <7K

marcotheturbosteamengine · Mon Jul 16, 2007 9:09 am

marcotheturbosteamengine wrote:
Piledriver wrote:
OK Marco, I have another possible use for the WBX rods. What HP and RPM would you consider a safe limit? Will have ARP2000 waveloks, shot peened perfect balance end to end etc, 24mm pin, 532g Cosworth slugs (weight with 24mm tapered pins), 71 stroke. Cam is a 119 on 112 centers, ceramic hybrid lifters.

They LOOK like stock T1 rods as far as all the cross sections, but I can't compare a set ATM.
Stock T1 rods are generally considered to be limited to 150HP and 7K, well prepped, and I would be pissed if the motor I'm working up couldn't ~ double that HP with the stock 2.0 Porsche heads (~180 CFM intakes)

Are the wasser rods a better alloy? Are they slightly beefier in some non-obvious way I'm not seeing? Even Jake mentioned he uses them in some combos...

Considering them for my T4 build on a T1-journal T4 crank.

turbo or NA? big differance![/quote]

ok i would say 280 real hp but only at 6500, the problems the is the waight hanging on the rod, rpm is what will kill the big end, as the rpm does up the load goes up at a factor rate! to be frank, with that cam you wont be reving it to get the power, 6000-6300rpm will be max power, so dont worry about it.
good luck..

DORIGTT · Post by **DORIGTT** » Mon Jul 16, 2007 2:29 pm

Then who makes the lightest piston that will allow that combination to survive at higher that 6,300rpm levels?

Didn't your engine rev and produce power at a higher rpm than that?

Post by **Piledriver** » Mon Jul 16, 2007 9:29 pm

The killer 400++ HP motor had h-beams and custom pistons IIRC.

I'll just run the EMW h-beams on one of Jakes cranks for this one, the rod ratio is better for the RPM range, and these weigh 550g with bolts.

(That was the original plan anyway)

DORIGTT · Post by **DORIGTT** » Tue Jul 17, 2007 8:23 am

I didn't think Jake did WBX stuff! From his posts I understood that if it had a radiator, he wouldn't touch it

Post by **Piledriver** » Tue Jul 17, 2007 10:50 am

DORIGTT wrote:I didn't think Jake did WBX stuff! From his posts I understood that if it had a radiator, he wouldn't touch it

The motor under consideration is a T4, was thinking of using the WBX rods on a 71mm T1 journal'd crank.