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Wed Feb 25, 2009 8:53 am

Im trying to build a bullet proof 1915 that will see occasional high rpm. Knowing that stock con rods are the weakest link, Im gonna replace them. Does anybody had any experience with the unitec race rods. And also will my rod ratio be compromised by going from stock lenth to 5.4?

Wed Feb 25, 2009 8:59 am

Stock rods are stronger than what people think. They are good to at least 150 HP. Its the bolts that are the weak link, depending on how long they've been on the rod, times they've been torqued, etc... Stocks rods with 3/8" ARP bolts are strong rods. Just my .02 cents.

Wed Feb 25, 2009 9:21 am

CB's unitech rods are a nice piece! I have them in my 2017, and another set in my dads 1641.

Wed Feb 25, 2009 9:24 am

Yes, UNITECH rods are nice pieces. You wont go wrong with a set.....

Wed Feb 25, 2009 9:25 am

Just buy some 5.4 Hbeams with ARP 3/8 rod bolts. After your done with the 1914 and you decide to build a stroker you can use those same rods for an 82mm stroke.

Wed Feb 25, 2009 9:28 am

Uni-Tech's are a good rod.
Stock stroke, small stroker, hell I even have them in a turbo pumping out 300hp. Sure they have there limits, but for most mild to performance builds there fine.
No issues what so ever.

Wed Feb 25, 2009 1:20 pm

Alan_U wrote: Just buy some 5.4 Hbeams with ARP 3/8 rod bolts. After your done with the 1914 and you decide to build a stroker you can use those same rods for an 82mm stroke.

Excellent advice! JMHO.

Wed Feb 25, 2009 1:21 pm

DarthWeber wrote: Alan_U wrote: Just buy some 5.4 Hbeams with ARP 3/8 rod bolts. After your done with the 1914 and you decide to build a stroker you can use those same rods for an 82mm stroke.

Excellent advice! JMHO.
I have 5.4 H Beams w/ 3/8" ARP bolts in my 2180.

Wed Feb 25, 2009 2:31 pm

SRP1 wrote: I have them in a turbo pumping out 300hp.

Probably the HD-Plus rod, same as I have in the 1915 turbo?
Agreed, excellent rod. They can take a pounding.
Stock rods are pretty strong too, but I wouldn't use them in a high output engine without rebuilding them with a better set of bolts first. If I remember correctly the HD-Plus rods I got from CB had the ARP 8740 bolts, but it would be nothing to swap those out for some 2000's if you felt you needed them.

Wed Feb 25, 2009 2:47 pm

miniman82 wrote: SRP1 wrote: I have them in a turbo pumping out 300hp.

Probably the HD-Plus rod, same as I have in the 1915 turbo?
Agreed, excellent rod. They can take a pounding.
Stock rods are pretty strong too, but I wouldn't use them in a high output engine without rebuilding them with a better set of bolts first. If I remember correctly the HD-Plus rods I got from CB had the ARP 8740 bolts, but it would be nothing to swap those out for some 2000's if you felt you needed them.

Correct Nick HD-Plus!!
BTW it takes 28psi of boost the bend (compress in my test) a stock VW rod.

Wed Feb 25, 2009 7:20 pm

SRP1 wrote: miniman82 wrote: SRP1 wrote: I have them in a turbo pumping out 300hp.

Probably the HD-Plus rod, same as I have in the 1915 turbo?
Agreed, excellent rod. They can take a pounding.
Stock rods are pretty strong too, but I wouldn't use them in a high output engine without rebuilding them with a better set of bolts first. If I remember correctly the HD-Plus rods I got from CB had the ARP 8740 bolts, but it would be nothing to swap those out for some 2000's if you felt you needed them.

BTW it takes 28psi of boost to bend (compress in my test) a stock VW rod.

But it takes a lot less to break the stock bolts! Gotta upgrade 'em.

Wed Feb 25, 2009 7:27 pm

why doesn't CB make the unitech plus in 5.5??? the regular unitechs are available in 5.5" I even called CB and asked them if they could custom make me a set of HD 5.5s but nope.... not that a mild 1955 is gonna need them I just wanted them for peace of mind :?

Wed Feb 25, 2009 7:35 pm

vugbug68 wrote: why doesn't CB make the unitech plus in 5.5???

Because they are intended to be a stronger-than-stock replacement rod,
that's why they only come in STD length. If you need longer/shorter,
just use the Super Race H-beams.

Wed Feb 25, 2009 8:07 pm

miniman82 wrote: SRP1 wrote: miniman82 wrote: SRP1 wrote: I have them in a turbo pumping out 300hp.

Probably the HD-Plus rod, same as I have in the 1915 turbo?
Agreed, excellent rod. They can take a pounding.
Stock rods are pretty strong too, but I wouldn't use them in a high output engine without rebuilding them with a better set of bolts first. If I remember correctly the HD-Plus rods I got from CB had the ARP 8740 bolts, but it would be nothing to swap those out for some 2000's if you felt you needed them.

BTW it takes 28psi of boost to bend (compress in my test) a stock VW rod.

But it takes a lot less to break the stock bolts! Gotta upgrade 'em.

I gotta tell you those rods had stock bolts in them.
Of the hundreds of rods I have used that are stock VW I have never had a rod bolt that was the direct route of failure, still.
Actually I have only had one rod bolt ever flat out fail and I had the torque wrench on it when that happened, it snapped in two right in the bench.
These days I think it would be absolutely insane to use the stock bolts, their to old and re-used for any performance application, this is just part of past endeavors I have had with stock rods and their bolts. Their both stronger than most people would ever give them credit for.

Thu Feb 26, 2009 2:40 am

miniman82 wrote: vugbug68 wrote: why doesn't CB make the unitech plus in 5.5???

Because they are intended to be a stronger-than-stock replacement rod,
that's why they only come in STD length. If you need longer/shorter,
just use the Super Race H-beams.

its funny they make the cheaper unitechs in 5.4 and 5.5" but the ones with better bolts only come in 5.4" I personally think it should be the other way around

Thu Feb 26, 2009 7:34 am

vugbug68 wrote: miniman82 wrote: vugbug68 wrote: why doesn't CB make the unitech plus in 5.5???

Because they are intended to be a stronger-than-stock replacement rod,
that's why they only come in STD length. If you need longer/shorter,
just use the Super Race H-beams.

its funny they make the cheaper unitechs in 5.4 and 5.5" but the ones with better bolts only come in 5.4" I personally think it should be the other way around

That's because if you need better bolts in a 5.5" rod then you should be running an H-beam rod anyway.

Thu Feb 26, 2009 9:24 am

^^ Right, so why make em....? If your buying 5.5 rods than your building a HP motor.

I have been running the old stock length unit-techs for over 5 years now..no problems. Just had the motor apart and they looked great.... Sees high RPM on occasion also :twisted:

Thu Feb 26, 2009 10:23 am

1955ccbug wrote: ^^ Right, so why make em....? If your buying 5.5 rods than your building a HP motor.

I have been running the old stock length unit-techs for over 5 years now..no problems. Just had the motor apart and they looked great.... Sees high RPM on occasion also :twisted:

There is a window for them, not all performance builds need an ARP 2000 bolt. 84 x ?? naturally aspirated low rpm stroker torque motor for example, no reason to run H-beam rods with 2000 bolts in that in that. The 5.500" Uni-Tech rod is more than enough.
That is just an example, there are many other applications that could use this rod.

Thu Feb 26, 2009 10:26 am

SRP1 wrote: 1955ccbug wrote: ^^ Right, so why make em....? If your buying 5.5 rods than your building a HP motor.

I have been running the old stock length unit-techs for over 5 years now..no problems. Just had the motor apart and they looked great.... Sees high RPM on occasion also :twisted:

There is a window for them, not all performance builds need an ARP 2000 bolt. 84 x ?? naturally aspirated low rpm stroker torque motor for example, no reason to run H-beam rods with 2000 bolts in that in that. The 5.500" Uni-Tech rod is more than enough.
That is just an example, there are many other applications that could use this rod.

That makes sense.