Butters

I'd be looking for constants between before and after the head gasket fix. Given what you described which was quick to overheat once you start driving ? not extended drives ? It sounds more than a fan / rad issue to me. You could have the FFP leaking into chambers, also sad to say an issue with the block. The cooling system could handle what ever small leak you have once you rev/drive it creates pressure and heat. If you haven't already, pressure test your cooling system.

This is the dyno for current setup, not got the 4inch exhaust yet, still ordering parts. Map sensor on dyno is a bit out, reads high.

Now don't hold back, you tell us how you really feel 🤣

Yep, you also said , been years and no eta. Just thought people would like the offical line and an update on timing. Forgive me for not crediting your prior post

Sorry if I missed it and to question but how are you 100% sure you are getting spark ? have you had a plug in a coil and seen it ? As spark + starter fluid always equal pop even if your timing is out. .... just pop out wrong side

PRP claim to be making rb26 cast block https://www.facebook.com/PlatinumRacingProducts/posts/pfbid0JvAYqGjU412b1XWvhg9kGHuV1Bt4rgbzTDGhwSSCA6Nq9k3nVqpDbHLvXeTpAhEQl

Is the new oil pressure sensor the same type ?

What's actually wrong with an N1 block ? I know PRP did a video giving them a hard time but they are a different casting, have a thicker deck. People have a lot of success with them for more than stock block power and not outright drag billet level. We seem spoilt in the RB world > No ? 600hp - new stock block - $5k 1000hp - new n1 block - $8k 3000hp - new billet block - $14k Not sure I see the gap in the market, unless you want 1500-2000hp cast block ?

Looking at that, it's going to flow more for sure. Be really interesting to see what the HP cost of it is at higher rpm. Please do report back how it goes.

That's impressive ! I should have been clear too, 6 speed H pattern syncro box is slower vs a syncro H pattern 5 speed at drags. A sequential or dog or both is not the same impact when added that extra shift.

Unless you have a t56 with double overdrive this doesn't make a lot of sense. The CD009 is .79 and and rb25 is 0.81 on overdrive, so near the same. The 6 gears are really nice to have a better spread of ratios from 1 to 5(1:1), Then still have an overdrive. I have found for drag racing the 6 speed is slower due to the more gear changes, not yet tried launching in 2nd. Amm how much are you expecting a DCT will cost ? When I looked at it, in aus a used DCT box $4-7k. Conversion kit is $4k landed. Controller and etc was $3k. So by the time its in the car , lets call it 15k+ DIY with a used box. Add $5k for someone to do it. If you want better clutches, which yes you do ($3-5K) and a box refresh add another $3k. Then you need tuning, which won't be quick or cheap. Blink and you have spent $30k hahaha

I've been looking at the DCT box conversions with much interest, i love the one in my Audi. So far not seen an example that really works better than an auto due to the programming required, as noted above. The idea has a lot of potential though. I have am r34 getrag gtr in one car and a os gearset rb25 in other, both are amazing to drive and both cars are over 600rwhp. The only down side to the OS is the ratios, specially first is really long for a street car. People LOVE the CD009 but stuffing around with adapter plates and clutches is a pita. Worth if it limited options are around like sr20 but not sure why people don't go gearsets for RB, you don't have to go dog people !

Agree on a bigger motor a bigger rear would be the go. I do wish I had a built bottom end to throw the extra 10psi at it to see what it would do. It's very tempting to test this out. You can get them in a vband flange turbine side which would make it near direct swap.

Don't think the g35-1050 will get there ? I am pretty close(720rear) on 26psi with scope for more boost and rpm. Very happy with the repsonse on a 2.6 with vcam, on a 3.2 it would be amazing.

Does VCAM work ... why yes, yes it does .... On vs Off, only tuning the low end, boost on gate. Final Result with some more boost - 718rwhp @28psi (Dyno reads boost high) Short nose RB26, stock bottom end. G35-1050 .86 rear vband VCAM and 264 exhaust cam Standard head, rebuilt , metal HG and ARP studs. E85 Link G4X plugin

I have a nismo 1.5 pro and I am old now and wouldn't use it in a street car. It's an amazing diff though, just be too annoying for weekly drives. Rebuilt stock gtr is great in the rear, it still skips slightly on tight tight slow turns but very minor. Drives both rears perfectly.

it's the .83 rear housing I assume by that you mean 4inch ? Decided to go that way for the future.

Car was tuned today. Seemed to struggle to make numbers again but got to a good place in the end. 722 rwhp on 26 psi climbing to 28psi. I was very happy. My tuner did think we should be nearer or over 800 on this boost. The VCAM worked amazing, picking up on average 50% more torque from 2000rpm to 5000rpm I still have a 3inch exhaust, which steps down twice from the 4inch dump. So that's next on the list to change. Not sure if 3.5 or 4 is the answer.

lol that is an interesting way to describe ...... Car is still not tuned yet, this was setup step prior, so hopefully in a couple of weeks time i will have a dyno graph.

889 rpm and 22 degree advance Sorry for the potato pic, its a screen shot of a video.

Well got my VCAM wired in today. Seems to be no issue activating it at low RPM/idle and this is with the kelfords 80lb springs . Still yet to get on dyno but this is a nice relief.

well if we can get back to car parts for a moment over questioning my life choices ... Here is some really good insight from Sam at Neat "Yes this is a characteristic of the V160 especially with a solid centre clutch and DMF removal. Rebuilding them can benefit a little as it tightens things up a bit, and we also do ISF treatment to the gear which can reduce noise, but not the rattle. Changing the oil to a light weight gear oil (75w85GL4) can benefit things a bit, as the OEM-fill ATF has almost no EP additives in it at all. You may find additional shift notchiness if you do this though, especially while cold." Ordered some oil, its a cheap thing to try and good to know a rebuild could possibly take the edge off.

Back to the RB20 Auto then eh .... Building a street car for me, how I want it, I accept plenty of things won't be like a stock car(exhaust one example). If i can make some things that bother me better why not try. I post here to gain the experience of others who may have used some of these parts, it's sad how often i regret that.

Its built to be a street car, I take the kids in it and hence I forked the coin for a syncro box, not dog engagement. It drives amazing and pretty much achieved my goal except for this noise and power goal ...

The conclusion I am on at the moment is I want a nismo twin plate mated to dual mass flywheel. That's the only zero noise, clutch engaged/not engaged option I can think of which of course does not exist. Going to email neat gearbox for some advice, they might have some options to drop the box noise.