Murray_Calavera

Unfortunately at this stage, I think this little project is a no-go. While technically you could do this without a wideband sensor, I consider it mandatory and it's not something I would attempt without it. Also you will need a laptop to be able to make changes to the tune as you drive around (drive, log, review the data, adjust, rinse-repeat) When I say VE I mean, Volumetric Efficiency. It should be one of the tuning options in your ECU software. I'm curious, how did you hook up your ECU and play around without a laptop?

yeah ok, lets just tick off a few things to see if this is doable - Do you have a wideband sensor and are able to log data to a laptop? Can you post a picture of your base timing map? (if you know what safe timing looks like and your base map is ok, feel free to skip this) How comfortable are you doing this? I'm guessing your tuning will be done in VE, do you understand what your changing when you change the numbers in the map? Also feel free to post up your fuel map, we might be able to give you suggested numbers that get you half way there.

Hey mate, With the base tunes that have been supplied, what issues are you having? I don't have any base maps for that ecu but getting a car running (not tuned) shouldn't take much time at all. I'm guessing you aren't intending to tune it yourself as you mention you want to get it to a tuner. Are you just trying to get it to a state that you can drive it on to a trailer?

Not sure if this is an option; 1. drop in a good wrecker motor. get yourself up and running again. 2. build the original motor in spare time. 3. sell wrecker motor, hopefully reclaim most of the original money invested. 4. drop in forged motor. Pretty shitty run of luck you've had lately, hopefully things pick up for you and the bike it found in one piece.

Your questions are something that you can measure yourself. Piston to valve clearance can be measured and the compression ratio can also be calculated after you guessed it, taking the correct measurements. After going through this nightmare of a failed ringland and spun bearing, do you really want to use another cast piston and risk another ringland failure? I'd strongly consider picking up some forged pistons, they really aren't that expensive in the grand scheme of things.

Have you taken it down the 1/4 mile? I would be very keen to see the trap speed

step 1. look around your house for the largest dinner plate you have. step 2. find a turbo that is bigger then the dinner plate. step 3. ??? step 4. profit!

Have a look at the Link KnockBlock, you might find it's worth going for as well.

Ugh, can't believe I missed it. Not off to a good start lol Thanks heaps though, looks like that's everything I was after

Hi all, I've got the R33 service manual that is all over the net, the 450ish page R33 engine manual, RB20, 25, 26 etc. I'm going to rebuild my RB25DET however the specs for the cylinder block isn't there. The manual has these details for the RB26DETT but no other motor. Looking at the numbers for the RB26DETT, a lot of them will be the same for the RB25 but some of them I am confident will not be correct for a RB25. Does anyone know where I can get a workshop manual covering the bottom end of the RB25? I'm happy to pay for the manual, I really just want to avoid buying something online which turns out to be the manual I already have.

The motor is getting torn down anyway as I've spun a bearing. The clock shows 250,000k's at the moment and I think it's had a hair cut when it came in to Australia. I haven't pulled apart the block yet but I'd be amazed if I could get away with a hone and reusing the factory pistons. I was thinking as I'll need to buy a set of oversize pistons, why not spend a little more and throw some forged pistons in instead. Initially I was thinking I should be able to get a set for around the $1,000 so only a bit more over stock and worth the money. If I'm paying double the cost of a factory piston, I'm not sure if it's worth it.

Hi all, I wanted to get some thoughts on running 4032 forged pistons. I'm only looking to make around 300kws as I'll be limited by stock exhaust manifold and internal gate. The car will mainly be used on the street however will get track abuse every other month or so. The more I think about it, 2618 just doesn't seem appropriate for my needs. I'll have to run a larger cylinder to wall clearance, so more engine wear, more blow by, more engine noise to filter out with the knock sensors etc and I'll never see anything close to the power they are rated at. The issue I'm having is trying to find 4032 pistons, it looks like Supertech and Mahle still do them however at a cost of about $1,500! I was expecting 4032 to be a cheaper option but I guess the price is due to the low demand. With my power figure in mind and the cost of 4032's, I'm starting to think if I should just run factory pistons? I had a quick look, seems like I should be able to get a set of new oversized stock pistons for about $700. Hmm...

That was a bit of a tease, let's see the timing table as well lol

Probably worth an update, so my daily drift car has done a big end bearing. Guess it was only a matter of time with no oil control mods done on the engine. Next one will have pump, sump, restrictors, drain etc etc - hopefully no more spun bearings. On the plus side, still haven't broken any driveline or suspension components.

All of them? Full exhaust Front mount Fuel system - injectors, rail, reg, fuel pump, etc ECU - flex sensor & wideband (you'll probably want fuel pressure, air temp, oil temp, oil pressure as well for engine protection etc) Dyno tuning costs Labor costs for above as I'm guessing you'll be paying to have it all done So only another $10,000 or so on top really lol

Hi all, I've pretty much got my shopping list sorted for the new fuel system, there is only one thing left to work out... dual entry or single entry setup for the fuel rail? I've been strongly recommended by a few people to run dual entry with the center return setup. Their main argument tends to be that due to the length of the rail, I might see a pressure drop across the rail and I could have a cylinder slightly lean out at times. This doesn't make a lot of sense to me, the way I see it if the fuel pump can keep up and the reg is doing it's job then the fuel pressure should always be equal across the rail. The more I look around the more I find people running both setups, and I can't seem to see any downsides performance wise either way. I'm keen to hear some more thoughts on the matter.

If your creative you can create your own form of traction control using the speed limiter function 1. Create the table using gear and rpm as your axis 2. Populate the tables, inputting the speed that you would achieve in each gear vs rpm with no wheel spin 3. In the main setup for the speed limiter, set the tolerance say 5 kph with ignition as the limit method 4. Then you can play with the ignition cut %, say start around 30% - 50% for a nice soft cut. See what works for you by adjusting the % cut I run a pro plug in, no complaints here

Yep, been closed for a while now

Thanks heaps for all the feedback everyone. Will be going with the ID1050X's setup for sure.

Yep have thought long and hard about that before I started my build, it's all been setup with 300kw in mind. If I want more, I'll build a turbo k swapped mx5 and the skyline will stay at 300kw.

So if we had 2 identical cars, one running 740s and the other running top feed, the top feed car would have a noticeably better idle? I've never been in a skyline with 740s but I'm guessing they idle fine? I just don't want to pay more for say a 5% improvement in idle quality

I appreciate that modern injectors are a better thing, but will I benefit from it if I'm only making 300kw? I can't see that I'd ever need more then base fuel pressure

Hi all, I'm about to put a set of injectors in and I can't seem to look past just throwing in a set of nismo 740s. I'm only looking to make around 300kw on flex, so I can't see a reason to use anything else. Doing a top feed conversion just seems like more work and cost for no real gain. I assume I'm correct in that the nismo 740s will idle fine, run e85 fine and cope with 300kw? So is there any real world advantage to using a modern injector, say ID1050X? Cheers!

No worries, I hadn't had any luck finding a place that could rebuild it but at least I have hope now. I'll keep digging. Also thanks for the Amayama back up plan, not keen to spend $1,600 however will if that's my only option

What state are you in? This would be legal in NSW once the car was engineered.