Jump to content
SAU Community

Recommended Posts

Personally I use JE/Nitto

Your topic may start discussion but wont provide a unanimous outcome.

I'm not aware of a comparison across the range.

Consider your build holistically !

against your goals, your capabilities and the depth of your wallet

I just found this, I wonder if mahle are the same as cosworth material composition.

I believe all CP pistons are made from 2618 alloy and Cosworth's Subaru pistons from 4032. 4032 is a high silicon alloy and the high silicon content provides a more durable wear surface and reduced expansion rate. 2618 is a denser alloy with higher tensile strength and a higher heat transfer rate.

4032 is a better option for a street application where low wear, long life, and reduced noise is of primary importance.

2618 is a better option for a race-specific application between the piston crown will run a little cooler and the piston will withstand detonation a little bit better than 4032. But the piston has less wear resistance and actually less stiffness.

However, Cosworth pistons use a boxed bridge design developed in F1. If you look at the back of the piston the pin bosses are reinforced with additional cross-struts and the pin itself is quite short. The bending loads on the pin bosses are reduced and overall the piston, skirt, and crown have greater rigidity. I don't think the Cosworth piston gives up anything in terms of overall strength compared to CP.

Cosworth pistons use a pin offset for reduced piston slap noise. CP pistons have no pin offset which is why they are not directional. Another reason for a very low noise level from Cosworth pistons.

Cosworth pistons have a polished crown which supposedly reduces carbon build up over time....probably another plus for a street application.

Theres a piston thread in the RB30 section, I think the wiseco are a good choice cause of tighter clearances possible but depends on power goals etc.. I chose to go with stock unopened bottom end cause its a pain and expensive to stuff around with engine builders that might stuff it up anyway... have faith in the OEM lol... nearly 30year old but yeah haha

So much potential for awesomeness. But to take it seriously before it reaches its inevitable train wreck of a conclusion.... Nah.

Carillo rods cause a bloke called Fred someone once used them in a race car which crashed into a wall and won a race. Must be awesome then.

Pistons. Well actually who cares. The most important thing about the piston in an rb26 is the rings and gettting a good seal. The rest of it doesnt matter. So best piston is a stock Nissan one. Take the Nissan out and you get oil puke unless you are really picky with your selection and run in.

CSB.

On the topic of rods, the weak point on H beams is usually the bolts anyway. I had to cough up an extra few hundred to get the ARP 625+ rod bolts in my Evo stroker kit.

Pistons... Well my stock Nissan VQ pistons have taken 40psi at the track many times, so have the rods. All I did to the stock engine was bolt the heads down harder with L19's after they lifted. As long as you keep the combustion temps under control the stock pistons would do fine.

  • Like 2

Tomei? My Tomei's are slight on startup. No piston slap and no blow by.

Its more of the engineering job that will make the most difference.

Make sure you use a good/the best engineer you can and whatever forged piston you use should do the job.

Depends on what you intend to do, there is no 1 rod or piston that's best for all situations everything is a compromise in certain directions.

Pistons can vary depending on what the build is, you wont build a high revving drag engine with the heaviest pistons with long skirts and you wont get far building a daily or long distance race engine with the lightest short skirt pistons.

Same deal on the rods, pins, rings etc.

Many people overlook the design aspect of parts and just see a brand name, put focus on the build purpose and then look at a piston or rod design to suit the application.

Basics like assembly weight which you want to keep low in high revving applications or highish to allow longevity through support and material strength for longer lasting lower RPM builds as some other basics to consider.

Its like comparing a Mahle and JE piston, 2 totally different designs from many points of view.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Did this end up working? Did you take some pictures?
    • And finally, the front lower mount. It was doubly weird. Firstly, the lower mount is held in with a bracket that has 3 bolts (it also acts as the steering lock stop), and then a nut on the shock lower mount itself. So, remove the 3x 14mm head bolts , then the 17mm nut that holds the shock in. From there, you can't actually remove the shock from the lower mount bolt (took me a while to work that out....) Sadly I don't have a pic of the other side, but the swaybar mounts to the same bolt that holds the shock in. You need to push that swaybar mount/bolt back so the shock can be pulled out past the lower control arm.  In this pic you can see the bolt partly pushed back, but it had to go further than that to release the shock. Once the shock is out, putting the new one in is "reverse of disassembly". Put the top of the shock through at least one hole and put a nut on loosely to hold it in place. Put the lower end in place and push the swaybar mount / shock bolt back in place, then loosely attach the other 2 top nuts. Bolt the bracket back in place with the 14mm head bolts and finally put the nut onto the lower bolt. Done....you have new suspension on your v37!
    • And now to the front.  No pics of the 3 nuts holding the front struts on, they are easy to spot. Undo 2 and leave the closest one on loosely. Underneath we have to deal with the wiring again, but this time its worse because the plug is behind the guard liner. You'll have to decide how much of the guard liner to remove, I undid the lower liner's top, inside and lower clips, but didn't pull it full off the guard. Same issue undoing the plug as at the rear, you need to firmly push the release clip from below while equally firmly gripping the plug body and pulling it out of  the socket. I used my fancy electrical disconnect pliers to get in there There is also one clip for the wiring, unlike at the rear I could not get behind it so just had to lever it up and out.....not in great condition to re-use in future.
    • Onto the rear lower shock mount. It's worth starting with a decent degrease to remove 10+ years of road grime, and perhaps also spray a penetrating oil on the shock lower nut. Don't forget to include the shock wiring and plug in the clean.... Deal with the wiring first; you need to release 2 clips where the wiring goes into the bracket (use long nose pliers behind the bracket to compress the clip so you can reuse it), and the rubber mount slides out, then release the plug.  I found it very hard to unplug, from underneath you can compress the tab with a screwdriver or similar, and gently but firmly pull the plug out of the socket (regular pliers may help but don't put too much pressure on the plastic. The lower mount is straightforward, 17mm nut and you can pull the shock out. As I wasn't putting a standard shock back in, I gave the car side wiring socket a generous gob of dialectric grease to keep crap out in the future. Putting the new shock in is straightforward, feed it into at least 1 of the bolt holes at the top and reach around to put a nut on it to hold it up. Then put on the other 2 top nuts loosely and put the shock onto the lower mounting bolt (you may need to lift the hub a little if the new shock is shorter). Tighten the lower nut and 3 upper nuts and you are done. In my case the BC Racing shocks came assembled for the fronts, but the rears needed to re-use the factory strut tops. For that you need spring compressors to take the pressure off the top nut (they are compressed enough when the spring can move between the top and bottom spring seats. Then a 17mm ring spanner to undo the nut while using an 8mm open spanner to stop the shaft turning (or, if you are really lucky you might get it off with a rattle gun).
    • You will now be able to lift the parcel shelf trim enough to get to the shock cover bolts; if you need to full remove the parcel shelf trim for some reason you also remove the escutcheons around the rear seat release and you will have to unplug the high stop light wiring from the boot. Next up is removal of the bracket; 6 nuts and a bolt Good news, you've finally got to the strut top! Remove the dust cover and the 3 shock mount nuts (perhaps leave 1 on lightly for now....) Same on the other side, but easier now you've done it all before
×
×
  • Create New...