My engine is out, let's make (almost) the best out of it.

[dj_rzn]

Okay, so after my car started to eat oil like a fatty I decided it's time for a rebuilt. (too bad as I only drove it 1500km)
The problem was a broken piston (I think it was firstly a oil pressure problem and then degenerated)

Now I want your support for telling me anything that I need to do extra as it will be easier once it's everything out. (I already ordered all the seals NEW, turbo is going hybrid and getting forged SUPERTECH pistons and forged rods.. I skipped the valves, is this such a biggie?)

 

[limbo118118]

Your want to do exhaust valves yes as well as new guides an stem seals while your there. That would be next weak link in my eyes..

 

[dj_rzn]

Okay, i will probably get those! Does the switch from small port to big port head needs any custom work? Or is it plug&play?

 

[dj_rzn]

Just bought valve guides and supertech steel exhaust valves. Nobody for the change from small port to big port?

 

[superkarl]

small port vs large port on anything other than big Turbos is a big debate. While most people on here have had success with hybrids and ko4s with largeports you lose low range torque. You'l find the yanks actually prefer small port in alot of cases and big power is still made.
based one what Bill and rtech have produced with hybrids though, large port is prob the better option

 

[<tuffty/>]

Smallport is a better bet if sticking to K04 framed turbo but if planning GT30 or bigger then large port... there is a case to use a small port for a track based car if using a smaller GT based turbo like the GT28/GTX28 though...

<tuffty/>

 

[dj_rzn]

Ok, then I will get the switch from small port to big port when I will get a bigger turbo. For now I will stick with the hybrid K04.

The guy who hybridized the turbo said that it should make 340hp at 1.7Bar.

I am planning on going stock (no remap) for 3000 - 4000km, will the car work normally? (hybrid turbo and 9.3:1 compression ratio supertech pistons)
Any advice on the oil that I should use? 5w-40 fully synthetic will be ok?

 

[superkarl]

to run in the engine initially you will need to use cheap mineral oil for a number of miles (mileage is anyones opinion) then you can run fully synth.

if not mapping straight away youl need to limit to actuator pressure by unplugging the n75.
certain parameters will still need to be checked like fueling and timjng, but you should be ok in that respect.
3-4000km is alot btw.

 

[dj_rzn]

Ok, so mineral oil for how many miles?
How many miles to run the engine until it gets ok to get a remap? (it was just an assumption the 3000 - 4000km, i just want to be safe)

 

[superkarl]

You could argue the rings are bedded in during the first 20 miles. But most people will run mineral for about 500 before swapping it out for synth.

 

[dj_rzn]

Well, it is a little problem and for the moment i won't be able to get the car our of the parking spot as the plates expired (long story). Can I burn 70 liters of gasoline (equivalent of 700km I guess) and then change oil ? (no running, just engine revved and idle)

 

[superkarl]

no, that's not how an engine is broken in.
i suggest you give running in techniques a google. Its been discussed on here lots of times. Before you do more bad than good

 

[<tuffty/>]

1.7bar is quite a lot of boost for a K04 hybrid... you will be mostly making heat running it that hard... just before it implodes...

<tuffty/>

 

[dj_rzn]

I don't think I am going to run it that high, I guess 1.55bar max should be ok.
I was reading about breaking in rebuilt engines and I figured out that I can do it on my local dyno, and also get immediately a remap (haha).Thanks guys for all the great info!