yeah i've read a fair bit on stretch gauges but they shouldn't even publish a torque figure unless they thought it would come reasonably close. It may be that the rod bolts need a few cycles to burnish the threads when using torque to do them up, and because those ones weren't done up from factory they didn't go through enough "polishing" cycles and as such 60ft/lb may not have been enough. who knows? every other set of rods were tight from factory.

 

some good info on this thread

 

The 'engine builder' probably used a garbage torque wrench.

 

Lol thanks I built it

 

I don't care who built it, most DIY'ers and a lot of shops use garbage torque wrenches.

 

So you haven't heard of HKS or Carrillo?

 

well i cant chime in on torque specs or stretching by i can tell ya that im using MAP's rods in my 2.4l also with wossner pistons.

Motor should be done in the next month and then to install it and then im bringing it to the dyno to tune and put it through its paces.

Ill be just going for a pump 93 tune first then probably pump/meth.

It would seem like TSComp has some good advice. And seeing as it didnt go so well that last time for ya maybe try and call a few shops as well and see what they think. Im sure even MAP will have some advice on using their rods. Seeing as there in the Rx-7. Ive seen that thing a few times and it is nuts. Nevermind the driver, drives the **** out of it. I watch that thing all over the track and he just doesnt let up. Its great.

 

I found that out the hard way once, thats why I went out and bought a SnapOn Tech Wrench, does it all.

The TECHWRENCH® is an electronic torque wrench. It was designed to provide basic electronic features, such as UNITS CONVERSION, (Nm, ft-lb and in-lb) TRACK, PEAK HOLD, PRESET, TOLERANCE and DATA STORAGE functions on a robust, yet ergonomically comfortable, wrench platform. It is priced to compete with mechanical bending beam, dial, preset and adjustable click-type torque wrenches

The "D" version (gray handle) features both a torque PRESET function and a TOLERANCE function. Certain keystrokes are necessary to enter the PRESET or TOLERANCE adjustment modes, so they are effectively "locked-out" from immediate changes. This emulates the mechanical fixed preset wrench. TOLERANCE is adjustable from 1% to 16% of the PRESET value. When the wrench is turned on, or any time the ON/ZERO button is pushed, the display shows the PRESET value for 2 seconds and then reverts to ZERO. The torque units of measure can be selected by using the UNITS pushbutton. As load is applied the display shows torque in the TRACK mode, emulating a mechanical dial wrench. When the torque reaches the PRESET value minus the TOLERANCE percent, the wrench beeps once and the handle vibrates, emulating a mechanical click wrench. Should the torque exceed the PRESET value plus the TOLERANCE percent, the wrench beeps three times. By exhibiting different signals between lower and upper TOLERANCE readings, a window of acceptable torque is established. This promotes quicker, less concerted, use of the wrench, which is more suitable to manufacturing environments. When load is released the display shows the PEAK torque applied for 10 seconds, flashing on and off. The wrench turns itself off after sitting idle for two minutes to conserve battery power. The wrench returns to the last PRESET, TOLERANCE and UNITS settings at power on.

The Red Handle is PRESET function only.

 

I got a question..... Who out there is using these rods on 500hp+?? I'd like to know cos ive ordered these rods but tbh I don't acing second thoughts now.... These rods can't be that bad can they

 

JohnBradley uses them up to 600whp

 

didnt know HKS made rods, but i know of carrillo yes. however i have no knowledge on their H beam stuff.. the only one i have looked up before was GSC, which is why i made the comment like i did. im sure there are a dozen other decent h beam's i dont know about.

 

The stretch tolerances of most rod bolts are so small that IMO, a decent stretch gauge and a decent DTI (such as Mitutoyo) is the only way to do it to ensure a 100% correct install.

There are just so many variations using a torque wrench, such as friction, bolt and rod thread tolerances, torque wrench quality and calibration (how many people use a top quality torque wrench and calibrate it every 6 months?)

As mentioned before, the rod bolt is one of the most critical components to get installed correctly and will massively reduce it's life if under or overstretched.

Also important when using a stretch gauge is to have a correctly profiled pointer that sits in the head recess and tail dimple, to ensure accurate readings.

Arrow Precision also make excellent H beam rods with 5/16" custom age 625+ bolts, weighing 525 grams each (compared to 590 grams for standard E9 rods) Manley I beams are 690g ea.

Below are pics of Arrow H beam rod bolt install, tolerance of the rod bolt stretch is 0.147-0.157, so 10 micron tolerance, so you can see the importance of accurate equipment even with the stretch method. Mitutoyo DTI I use has 1 micron resolution and accurate to 2 microns (2 thousandths of a millimetre)
First pic before stretch, loose, second after tightening;

 

you'd think if theres that much variance manley wouldn't even give out torque values. on a side note has anyone here gotten rods that didn't have their rod bolts torqued while in the box??

 

Ya Mitutoyo is one of the best.. if not the best. that looks like a really cool gauge. When measuring mine i had to rock back and forth to find the peak areas of stretch on dial gauge. would of been a absolute ***** on my back LOL. I used a Jegs stretch gauge setup modified.

What you mentioned is very important.. making sure the ends sit in the dimples perfect or it can throw off spec.

 

In all honesty you should of done that yourself when finding / setting rod bearing clearances. sounds like you didn't measure anything yourself?

who set the clearances or provided what bearing thicknesses to use for your build? machine shop? if so it is there job to assure its good with proper measuring tools, micrometers, dial bore gauges, etc.

Its required to measure the Inner diameter of the rod caps tightened to spec in order to know/choose proper bearing thickness required to meet your personal specifications for your engines final clearance assembly.