Jump to content
SAU Community

Recommended Posts

my is engine knocked and a friend of mine has sn rb26dett in which he recently replance his stock pistons with forged ones, he said i could have the stock ones if i wanted. Has anyone tried the swapping rb26dett pistons into the rb25, what time compression could i expect, are the pistons stronger, any info would be appreciated.

Link to comment
https://www.sau.com.au/forums/topic/273433-rb26dett-pistons-in-rb25det/
Share on other sites

ok i have put the pistons in the block using rb25det rods and an rb25det crank, the sides of the pistobns however dont reach the top of the engine block, any idea how this affects the compression ratio

++++

hey kilo_gulf,

those two engines do have the same bore size but have a slightly different stroke.

rb25 has a bore x stroke of 86 X 71.7

rb26 has a bore x stroke of 86 X 73.7

take notice to the 2 mm difference in stroke.

THE PISTONS THAT CAME IN THE MOTOR ARE OK , THERE AFTERMARKET, I HAVENT BEEN ABLE TO IDENTIFY THEM, BUT THEY DONT HAVE A DOME ON TOP LIKE THE RB25DET OR RB26DETT PISTONS, THEYRE FLAT TOPS. I DID A COMPRESSION TEST ON THEM ABOUT A MONT BACK AND THEY AVERAGED BETWEEN 115 TO 120 PSI PER CYLINDER. I DONT KNOW WHY THE PERSON WHO BUILT THE ENGINE WOULD USE THEM MY GUESS IS NITROUS, IN ANY EVENT THATS WHERE I STARTED. THUS WHEN THE RB26 PISTONS BECAME AVAILABLE I JUMPED AT THE CHANCE HOPING FOR BETTER COMPRESSION BUT IT SEEMS ILL BE RIGHT WHERE I STARTED.

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

    • After @Kinkstaah debacle, I'd never want to try and get it right 😛
    • The hood lines up with the fenders. The front bar doesn't perfectly line up with the fenders where the wheel arch is. You have to 'squeeze' the front bar 'in' as it wants to naturally flare out and be longer on the sides. There's a few threads where people notice this when they only swap a GTR style bumper and front bar. Unless you have genuine OEM items - you may be better served getting conversion kits. There are GTT bumpers to fit GTR hoods. There are GTR hoods (non genuine) to fit the GTT bracketry. MAY  
    • The real question is, on some of those wild roads they call highways, how many times did a farmer in an old ute from the early 2000s blaze past you over double lines?   Tassie is a wild and really cool place, and after doing a work related road trip there January of 24, I understand why Targa Tasmania is ran there, and is so tough to do well at! We had a brand new Camry Hybrid that handled quite nicely, and thankfully weren't in an old car, because cresting some of those hills in a 100kmh zone for it to suddenly be like "surprise f**kers, this is a recommended 30kmh hard right turn" wouldn't be pretty. We weren't racing the Camry around, but we weren't slouching in the bends either. But my lord those old farmers know their old clapped out utes, and those roads, as they were absolutely hammering it!   You're also super lucky to make it up to Mt Wellingtong this time of year. It's often road closed with snow/ice! Also, I hope you hit up Salamander Road in Hobart for some insanely good food (I highly recommend the dimly lit Irish pub for a Guiness Pie, or even the bangers and mash!!!)   How long did the Ferry take to get across? I want to do a road trip of Tas on my own time, but I get horrifically sea sick, and I don't want me on the Ferry, just the car 😛
    • So far so good, about 30km on it so far and nothing out of sorts yet thankfully
    • Look at @Kinkstaah's thread on the issue.
×
×
  • Create New...