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  • 3 weeks later...

Cheers Jordy!

With the battery box ready to go, I spent a lot of time measuring & test fitting it on the passenger side of the boot.

I'll be fixing it down with M10 bolts, so I carefully marked the set-out & drilled the floor pan. To be safe I measured both underneath & inside the boot - it's very important this is done otherwise you risk drilling through the chassis rail material.

Each hole obviously brush touched with etch primer to prevent rust. & I'll pack the boot floor up with some 5mm plywood pieces to keep it all nice & flat.

I'll post pics of that next weekend, and you'll all be happy to know that's when the cams, valve springs, rocker arm stoppers, & fresh oem bits (e.g. valve stem seals, collets etc) for the head are going in.

MHX5NBYh.jpg

But he likes racing pedigree items.. like mentioned over on Nissan Silvia LOL.

Personally would have used a dry cell and mounted it on the hump, on the opposite side of the fuel tank access. More boot space for E85 tanks going to the track :)

Fatz, please elaborate? Keep in mind I'm not running a lead acid battery, it'll be a lithium motorbike battery....

Johnny, that wasn't an option for me as that'd be an instant defect having an exposed battery in the boot (the law doesn't differentiate between lead acid & dry cell). Skylines get away with it due to the cabin being completely seperated...

 

 

BTW... put in headstuds at a minimum.. I am assuming the cams are coming out one day?

I recently tuned Killaflop's S15 from Nissan Silvia / trak-life crew member and it's got about 1.8bar of boost going into the stock motor hehe... however Mr Fuel pump wasn't happy and we didn't delete the OEM pressure relief valve, so with 1150cc injectors we were at 100% DC.

Round 2 soon, hopefully will see 2 bar into the motor with just studs, a tomei gasket and poncams

  • 2 months later...

Johnny - im running an R33 GTR relief valve to avoid that problem. After a lot of thought I decided it's best to take the head off & stuff it full of the good stuff. Car will be getting floated to the engine builder this weekend. ....will leave bottom end stock for now unless it looks in bad shape when the motor gets torn down.

Going big valve so head will be ported & polished to within an inch of its life, and ill be getting rid of the squish pads for hemi chamber .

Spec is:

  • Tomei Poncams - 256 deg, 11.5mm lift
  • Tomei +1mm oversize valves
  • Tomei Type A Valve Springs
  • Tomei Rocker Arm Stoppers
  • JUN or Naprec Valve Guides (desperately chasing the valve guides as they're the only thing I don't have yet....)
  • ARP Head Studs
  • Tomei 1.2mm Metal Headgasket
  • Valve spring sheets
  • Brand New OEM Valve Spring Collets, Cam Washers, Retainers, Rocker Guides, Valve Stem Seals, Valve Seats

Rev Limit will be 7500rpm for now as I'd like to get a decent life out of the head....will keep everyone posted :)

 

 

 

 

better not to run any relief valve.. just pump -> line -> filter -> rail

3x S15s I've tuned recently, I deleted all 3x relief valves.. pieces of shit, you add boost and it loses fuel pressure.

On 9/21/2016 at 8:02 PM, BakemonoRicer said:
  • JUN or Naprec Valve Guides (desperately chasing the valve guides as they're the only thing I don't have yet....)

whats wrong with BC? can get most of the important bits for the head all in one package. much less lube involved compared to JUN and Naprec

http://www.briancrower.com/makes/nissan/sr20det_valvetrain.shtml

Ended up going with the JUN valve guides as Naprec didn't get back to me....they're getting shipped out tomorrow so I think best case scenario is they'll be here Tuesday.

Not too keen on the BC stuff, just comes down to personal preference really man. Plus, I'd rather stick with the stronger & slightly heavier OEM retainers.

  • 6 months later...

Head currently being disassembled and getting packed for overseas shipping soon.

Have been in talks with a few big machine shops in JPN and now one of them will be doing the work - porting & polishing the head to their specs & doing the machining for the big valves & hemi chamber (e.g. no squish pads)

Dose

Im suprised more people dont do it actually. As youd know the gtir head came from the factory without squish pads and from speaking to Naprec/JUN its definitely the way to go. Yet in Aus not many people do it...im wondering why..

 

You talking conversion to mechanical/lash setup for cams? Just means you can run aggressive ramp cams. Worthwhile for track NA motors but I really don't think it's worth the effort for turbo. My motor is gtir and you can't get rockers unless you go through Naprec (unless someone in the US (mazworx?) sell a conversion kit or something). I have pictures of the different rockers but no access to them right now.
I think oversized valves to improve head flow would be a better option, since the DE heads don't flow anywhere near as good as the VE heads.

Leroy - yes oversized valves will be getting installed (+1mm). The combustion chamber in the GTIR head doesnt have squish/quench pads, making the head a lot more detonation resistant than S13/14/15 SR heads. Seeing as the heads getting shipped  to Japan, I may as well future proof it for man boost.

Below on the right is an SR chamber with the squish pads removed.

13700233_272783309753761_769526829315289

GTiR combustion chamber is also bigger, so will lower compression. How are you going to mate the head to the block? What intake/runners are you going to use? Not much is interchangeable. I actually don't think any of it is.

Leroy, compression drops by .2 once the pads are taken out, with the 1.2mm tomei headgasket i'll retain standard 8.5:1 compression ratio.

Still using the S15 head mate, just taking out squish pads like a GTIR head is all I'm saying : )

It's fairly common with the high hp RB builds to take out either one or both squish pads. Piggaz has done this, so did Elrodeo666 from memory.

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