Rb26dett Cracked Block

[mddR33]

Hi guys,

Recently had my R33 GTR at the mechanic, for fitting the (I had hoped) last few mods to my car.

Upon pick up, they have told me that they have noticed a crack in the engine block (near the turbo oil feed, between cylinders 3 and 4) that is allowing coolant to seap out. They told me that it was enough to form a small puddle on the floor, though I have now had the car back in my garage for 24hrs and the floor is clean.

Anyway, unfortunately I guess this means I am probably up for another $10k or so to get the engine out and have an N1 block fitted (Im not a mechanic so can't do it myself), and hopefully forged internals as well. Super bummed, as I had planned to just enjoy the car now, as I've already thrown about 25k at it in parts and labour.

A few questions:

1. Are there any common causes for a cracked block? Mechanic said it is common on RB26's, due to some twisting because of front end torque?) I could barely find any info on google relating to cracked RB26 blocks.

2. How likely is it that this crack will get bigger quickly? (Potentially a "how long is a piece of string question", but if anyone has had any experience before?)

3. Any suggestions for the build of the bottom end? Do's or don'ts? Not looking for massive power (currently 300awkw with -7 turbos) but any suggestions based on past experience would be great. I'm not ruling out buying a pre-built engine if it was close to my budget, then just re-fitting any parts needed from my existing engine.

Cheers!

[GTRPSI]

Its a common problem when 4wd launching, right between Cyl 3 and 4, its the weakest part of the block, extra oil passages run across there.

Its the front diff forces being put though the block that twists it.

Many people throw and inch or 2 of hardblok into the water jackets to help strengthen the blocks up a bit more.

First get a second opinion to make sure its actually cracked and not a bad fitting or welsh plug.

[Duncan]

yeah assuming it's not a welsh plug, it will be engine out and new block required to fix it.

however, depending on what you choose to do at the same time, it doesn't have to be that expensive. A second hand block, reuse existing pistons if they are already oversize ($0) or new pistons if not ($1k) plus basic machining, rings and bearings. You can do all that for under $1k + pistons if needed.

[Dahtone Racing]

Seen it heaps, our test car has broken 4 05U blocks all from massive launches with 700 - 750 awhp, tried all different combos with grout, without grout, more grout, less grout, etc, etc.
N1 block going in it this time and then find the limits of that.

[GTR-N1]

Q2 You might be able to buy a bit of time with "Intelligence Polymer. Costs $150 and you need to run it in the engine for 500km until it fills any cracks and sets. It's supposed to be flexible too under heat and not get brittle. Up to you...

[thewayweroll]

We have used Liquid intelligence 245 several times,not on performance cars ,if you follow the instructions exactly it works !! I think it is about $85 from Autobarn as stated above it may get you out of trouble, we have had it in a work car for 2 years ,it fixed a badly blown head gasket .