RB25 Build Thread

[adzsy]

Copied From SXOC

Well after a year without an s-body I seem to have fallen back into the game. The S14a got sold along with the Navara in a bid to limit myself to one sensible car whilst my wife was on maternity leave. So I bought a Black R33 GTR V-Spec. As nice as it was, it never really exited me so now my wife is back at work the GTR has gone, I’ve bought an L200 animal and the plan was to buy a TA22 1970’s. Then this came up.

It’s a NA Spec S with auto box and a mind blowing 160 BHP with a fair few battle scars around the bumpers and wings, and even had a smashed rear window and broken door locks. It is however completely rust free and very straight underneath it all. It’s done just 62000 kms.
On a whim, I flew to Dublin paid £2850 cash and ‘transported’ it home.
Obviously my first and only thought was RB25. So here I am with this in my garage, and an RB25 conversion package ordered from the GTR shop, and some other bits and pieces ordered from Jap Performance Parts.
The work will commence shortly.

 

[adzsy]

First goodies have arrived. Aero Side Skirts.

Nothing like having your desk at work surrounded by car related bits and tools.

 

[adzsy]

I have had to register it as it is imported from Ireland, so it now has 12 months MOT (pretty useless as it will be sat in the garage).
Registration certificate has arrived today. They are supposed to be randomly picked but my reg is T720 DET. If only it was an S -reg It could have read S7 20 DET.
Maybe someone sat in the DVLA knows what I have and done me a favour? or just coincidence?

I have started to remove the broken glass from the rear quarter and clear the adhesive. Any hints on fitting the new window appreciated.
Looks like someone has bodged it previously with drainpipe sealer as it is really tacky still.

 

[adzsy]

Engine removal has commenced. I can't dedicate a huge amount of time to this as I have a new house with extensions and things being planned, so as and when I have been removing parts.

http://i707.photobucket.com/albums/ww71/adz1282/S15%20Silvia/06062011281.jpg[/IMG

The front wing also needs replacing at some point.
[IMG]http://i707.photobucket.com/albums/ww71/adz1282/S15%20Silvia/06062011276.jpg

 

[adzsy]

Well as I have recently found out the RB25 is prone to exhaust manifold studs shearing.....I have three that are gone.

So using a stud removal tool (the left hand tap type) 2 came out failry well, the third needed drilling and tapping.

 

[adzsy]

Going with advice from here I am using the GTST subframe and engine mounts. I have yet to see much difference, anyone know what it is? does it sit lower?
A quick shot blast

and a lick of paint

 

[adzsy]

I have some Alloy 825 (commonly known as Inconel 825) 10mm bar. So I am going to make some new studs froms that. Still not as strong in tension as a high tensile steel but at least it won't rust and much better that 304 or 316. I have been toying with the idea of a tubular manifold, but can't help thinking it's not worth it for under 400bhp. So I may just get the cast one skimmed.

Making your own studs take forever, I planned to have the manifold on the head, and subframe in the car last night. I made 3 studs!
This **** is a bugger to thread and cut through

 

[adzsy]

Well I haven't done much the last couple of weeks. Here is a list.
Ordered new steering rack, shot blasted it but not painted it yet.
Shot blasted engine mounts
Bought a Japspeed Manifold.

I have cut some gaskets out of flat reinforced graphite too.
Hope fully Once these bits are fitted I can drop the engine in

 

[adzsy]

The engine is in. I um'd and r'd about dropping it lower but after a conversation with Martin Battye at MB Automotive I decided to go for the standard mounts and get a Greddy style plenum.

Some much needed help, cheers Andy.

Looking back I should have dropped the car over the engine, but it did go in.....just!


This arrived today so is next on the list.

 

[adzsy]

I have removed the inlet manifold and started swapping all the parts over. Whilst turning the fuel pressure regulator 180deg I managed to snap it!

Heres the injectors being rotated 180deg too. I didn't damage these thankfully.

Well I will update fully when get some pics but for now I have
Fitted the inlet manifold....mostly, just need to hook up the Q45 throttle body
Fitted the manual pedals, just waiting on a Clutch master cylinder to arrive.
Fitted a 5Zigen cat back, but I need to mod my down pipe to mate up to the RB elbow.
I started thinking about the wiring. There is next to no information on the S15 Spec S Auto with regards to wiring....ECU / F4 pinouts. Any help here would be much appreciated.

 

[adzsy]

Bit of an update and some pics.
Just part fitted the FMIC. I need to fab a pipe from the core to the Q45 throttle body and include the dump valve somewhere in that.

 

[adzsy]

some more pics

Water bottle rotated.

and heres a pic of the downpipe fitted. Perfect fit!

 

[adzsy]

Well I have been busy making up the wiring loom. Not sure if I am doing it right or if it will work, but everything seems to have made sense so far.
More importantly I bought these off ianlea73. Not got them yet, there at my parents house 200 miles away but can't wait to try them on,
18x10 et 22 rear wheels and 18x9 et 38 front wheels.

DR Prop (http://drprop.co.uk) has made me up a 1 piece prop shaft using the Skyline bits and pieces.
I'm really happy with it, and for £135 balanced and shipped you can't grumble.

So this will be fitted tonight along with new belts.

 

[adzsy]

I just sent him the R33 complete prop and he cut the ends off to use because the Spec S Prop was about 2" diameter. I sent him this sketch; yours will be different for an S14.

My gearstick will sit about 1.5" further forward but shout be ok.
The holes on the gearbox mount did not line up. If you cut the section out between the two holes and make it a long slot you can mount it but this is only on two bolts not four. I want to drop mine about 5-10mm anyway so will just weld a bit of bar on with the additional holes required to mount it.

 

[adzsy]

So its in and running. When I first got it started the manifold starting glowing red after about 10mins on idle.
The threee things I did where;
1 - Took the CAS off to check the Cam belt hadn't slipped a tooth and re-fitted somewhere close to how it came off.
2 - Removed the Fast idle mechanism in the Q45 throttle body. The RB25 has it's own by means off AAV valve.
3 - Topped up the 1 year old fuel with fresh unleaded.

One of these three sorted.​

 

[adzsy]

Here's a photo of the engine bay;

 

[adzsy]

I am a bit bored of fiddly stuff now, so to keep momentum, inspiration and sanity I have fitted the Tein sideways master Coilovers and Blitz technospeed's. I have loved these wheels even from my Nova days (17) and now have a set thirteen years later. So the fact the rears arches sit on the tyres and the front coilovers rub on the inner rim won't stop me from fitted them. 20mm spacers on the front should do nicely. Arch enemy's website says ' we'll make your car fit your wheels'.........mental..... that will do me. A call to Arch Enemy will sort this out.

 

[adzsy]

Not really much to say at the moment. Just been fiddling with idle control valves and timing etc.
I need funds for two big spends -
Bodywork, I am gona take it somewhere with all my bits and say 'make it so'
Engine Map - Plan is to take it to MB Automotive, for £600 Martin will supply a 300ZX ECU a nistune chip and map it - Sorted!

I am itching to get it out on the road.​

 

[adzsy]

This is a boring update but essential for those doing similar conversions.
We all know about the interchangability between S13 and S14 clutch pedal and clutch master cylinders I won't discuss this. But as for the S14 and S15 I found no direct info on this so here is what I now know.
The s14 and S15 have different clutch pedals - not interchangeable.
The s14 and S15 have different clutch master cylinders - not interchangeable. The main housing is the same, but the s15 one has a longer push rod assembly to reach the pedal.

I have an S15 pedal and an S14 master cylinder, so the following pics should show how I made it fit with an M8 connector cut down by 8mm in length.

 

[Feast Japan]

Have a friend over here that I supplied a Spec S to. He popped in an RB26 just recently. Had maybe 10mm of clearance between the water pump and electric fans.

How is the inner casting inside that plenum you bought? Ive seen some replica's and they were pretty nasty inside.