R33 GTR Rebuild + Upgrading

[Duncan]

So, for sumps, yes the trust and many other sumps are lower than the cross member. I changed across to a slightly larger but higher high octane sump after I knocked the drain plug out of the sump in my race car on a ripple strip. 

Guessing you are in the US so you exchanging a sump with an Australian shop is not simple; so keep in mind most sump extensions are cut and welded into your current sump, and that welding cast aluminium properly is a specialist job.

BTW I don't agree that an extended sump is necessary for road use, I use a standard sump in my rb30 stagea. It is only a problem for track use with the combination of extended high revs and long high g corners.

When people talk about changing the front diff they mean putting a quaife diff centre in. This is a helical diff that greatly reduces front wheel spin without adding much understeer under power.

In my opinion, the spline drive oil pump is overkill (and harder to fit). The regular Nitto/Tomei style pump is fine (your 33 should already have the longer style oil pump drive on the crank).

[oSkylines]

21 minutes ago, Duncan said:

So, for sumps, yes the trust and many other sumps are lower than the cross member. I changed across to a slightly larger but higher high octane sump after I knocked the drain plug out of the sump in my race car on a ripple strip. 

Guessing you are in the US so you exchanging a sump with an Australian shop is not simple; so keep in mind most sump extensions are cut and welded into your current sump, and that welding cast aluminium properly is a specialist job.

BTW I don't agree that an extended sump is necessary for road use, I use a standard sump in my rb30 stagea. It is only a problem for track use with the combination of extended high revs and long high g corners.

When people talk about changing the front diff they mean putting a quaife diff centre in. This is a helical diff that greatly reduces front wheel spin without adding much understeer under power.

In my opinion, the spline drive oil pump is overkill (and harder to fit). The regular Nitto/Tomei style pump is fine (your 33 should already have the longer style oil pump drive on the crank).

So, i could look into a regular nitto or tomei pump, but the price difference doesnt seem that far off, but if it saves me in labor when I'm having it assembled , thats fine with me. 

The one thing i question is that I have heard about a million times that if you upgrade the oil pump, you have to upgrade the sump or you're gunna end up running into issues. Is this not the case with the nitto/tomei style pumps? While I would like to avoid another several hundred in parts short term, plus the labor , I surely dont want to blow it up from pumping air instead of oil due to lacking the appropriate amount of oil/ baffles / etc if the pump requires it

 

As for the front diff, Im happy enough there for the time being, I will likely pass this up on at least my initial set of installations. Im really trying to get the MUST HAVES done while the engine is out. Honestly its unlikely i'll ever see a track, and Im not drag racing anybody. Just spirited street driving, where safety and a lack of prying eyes allows.

Edited September 3, 2023 by oSkylines

[Dose Pipe Sutututu]

2 hours ago, Duncan said:

BTW I don't agree that an extended sump is necessary for road use, I use a standard sump in my rb30 stagea

Pop in a higher flowing aftermarket oil pump and using the stock sump is asking for issues.

[joshuaho96]

7 hours ago, oSkylines said:

aye theres the rub. From 420 up to 810 usd with the ballast resistor delete, which i assume is what it means when it says that they are high impedance and need the removal of the resistor pack in the first link. So it looks like nzefi is the way to go , if the option for the ballast resistor delete is bundled in. Would've likely missed that without you pointing that out. Thank you very much.

NZEFI is in NZ, so it's 705 NZD. 

[oSkylines]

18 minutes ago, joshuaho96 said:

NZEFI is in NZ, so it's 705 NZD. 

Yeah i have it in my cart now, I am US , so its 764 usd with shipping. Which isnt quite as bad as 810 , but still more expensive than the 400 dollars that i was looking at before realizing there were some extra bits needed to get it working lol. But overall, im fine with paying the price to know they are genuine and have everything i need to make sure it goes smooth.

[oSkylines]

5 minutes ago, oSkylines said:

Yeah i have it in my cart now, I am US , so its 764 usd with shipping. Which isnt quite as bad as 810 , but still more expensive than the 400 dollars that i was looking at before realizing there were some extra bits needed to get it working lol. But overall, im fine with paying the price to know they are genuine and have everything i need to make sure it goes smooth.

I just purchased them, and it was showing strangely, it actually was only a bit under 500 usd ! thats a pleasant surprise ! lol

[Duncan]

That's what happens when you are buying in hard currency, good luck to you

[GTSBoy]

Here's the rules.

1. If the engine is coming out, and you really don't want to pull it out again, (and no-one really wants to pull it out again), then you do absolutely everything that has to be done. That list depends on whether you want to do the barest minimum, and therefore are not doing much in the way of upgrades, or if you want to do a few small upgrades....just 'coz. But that last bit leads to you having to do ABSOLUTELY everything.

2. As the guys above say - no GTR should have the engine come out and go back in with a stock diff. Quaife front centre is the very best thing you can do there.

3. Because you want to upgrade the power, then you want to upgrade the oil pump. But you cannot consider upgrading the oil pump (beyond trivial upgrades to materials, like billet gears in stock housing) without dealing with the fact that it will empty the sump and put it in the head. So....sump upgrade. Find a local race fabricator who knows what he's going and do the sump. Should be able to garner input into what it should look like from the interwebs. Plenty of youtube vids on the subject.

4. But you cannot just allow the thing to take the oil out of the sump and put it in the head. You have to deal with that. So, off you go to the oil control thread in these very forums and read the last 150 pages or so. You need extra breathers run from the sump to the crankcase breather system, properly selected restrictors in the head, decent oil-air separator and catchcan system, etc.

5. In general, the stuff that has been designed for GTRs and 26s in Australia and NZ in the last 10-15 years is far superior to all the old Jap branded stuff.

[oSkylines]

6 hours ago, GTSBoy said:

Here's the rules.

1. If the engine is coming out, and you really don't want to pull it out again, (and no-one really wants to pull it out again), then you do absolutely everything that has to be done. That list depends on whether you want to do the barest minimum, and therefore are not doing much in the way of upgrades, or if you want to do a few small upgrades....just 'coz. But that last bit leads to you having to do ABSOLUTELY everything.

2. As the guys above say - no GTR should have the engine come out and go back in with a stock diff. Quaife front centre is the very best thing you can do there.

3. Because you want to upgrade the power, then you want to upgrade the oil pump. But you cannot consider upgrading the oil pump (beyond trivial upgrades to materials, like billet gears in stock housing) without dealing with the fact that it will empty the sump and put it in the head. So....sump upgrade. Find a local race fabricator who knows what he's going and do the sump. Should be able to garner input into what it should look like from the interwebs. Plenty of youtube vids on the subject.

4. But you cannot just allow the thing to take the oil out of the sump and put it in the head. You have to deal with that. So, off you go to the oil control thread in these very forums and read the last 150 pages or so. You need extra breathers run from the sump to the crankcase breather system, properly selected restrictors in the head, decent oil-air separator and catchcan system, etc.

5. In general, the stuff that has been designed for GTRs and 26s in Australia and NZ in the last 10-15 years is far superior to all the old Jap branded stuff.

I’ve gathered the aussies and NZ def have their skylines sorted out ,but I’m not totally familiar with just how much there is out there . That being said I’ve basically been following these trains of thought. 
 

y’all are really advocating for that diff, so I’ll add it on. I’m going to assume it makes a significant difference from the advocation. I just didnt want to add it for people thinking it’s going to be a track car , when it’s going to very much more be a pleasure driver on the road with a little more hop/torque for the smile factor .  But if “no car should be allowed to pull engine and not replace front diff”  , that’s a pretty hard stance, it must make a difference 

 

 

I do need to read more about the oil system  and the needs there. I’ve been going over everything else , spent probably 20-30 hours in the past 3 days already to make lists / prices I have now 

[oSkylines]

So far opted to leave out the diff for the simple fact of funding, and am leaning into the Nitto oil pump, RIPS sump kit, and High Octane washer bottle replacment/ catch can setup. Still reading about the restrictors/ stuff regarding head drains/ extra breathers? , and the like. No shortage of things to sift through .

[oSkylines]

Does anybody else have any input on the nismo clutch being capable at this hp range of 450-500 whp? I hear it feels substantially better than the OS Giken and is cheaper , but some years ago Geoff had advised against it , stating a previous customer of theirs just had to have it removed due to not being able to appropriately clamp down at that rating . On proper claims to be able to take like 600 lbs of torque or something like that, so it SHOULD be fine but further experienced people feel free to weigh in 

[Duncan]

You are right at the top of of a good single clutch clamping load at the low end of your target (340kw), planning for a twin would be a good idea

[oSkylines]

20 minutes ago, Duncan said:

You are right at the top of of a good single clutch clamping load at the low end of your target (340kw), planning for a twin would be a good idea

so straying from the Giken and leaning towards the nismo coppermix twin plate seems reasonable ? 

https://www.nengun.com/nismo/super-coppermix-twin-plate-clutch

im hoping to locate one outside of japan with slightly more reasonable shipping as nengun and justjap and the like are absolutely horrid with shipping prices to the US, But if the nismo is more drivable ill def consider that over the giken, especially ( if i can find a good location to ship from) with it being a few hundred USD less

[oSkylines]

On 9/4/2023 at 2:48 AM, GTSBoy said:

Here's the rules.

4. But you cannot just allow the thing to take the oil out of the sump and put it in the head. You have to deal with that. So, off you go to the oil control thread in these very forums and read the last 150 pages or so. You need extra breathers run from the sump to the crankcase breather system, properly selected restrictors in the head, decent oil-air separator and catchcan system, etc.

is there any harm in restriction of the oil to the head " too much" , tomei is 1.5mm, some others are 1 and 1.2 , I see for things like drifting and the like, 1mm is suggested, and they are all basically the same price, so i was curious is 1mm just overall " more protection" or can it cause any unintended harm with less aggressive applications

Edited September 5, 2023 by oSkylines

[GTSBoy]

2 minutes ago, oSkylines said:

is there any harm in restriction of the oil to the head " too much" , tomei is 1.5mm, some others are 1 and 1.2 , I see for things like drifting and the like, 1mm is suggested, and they are all basically the same price, so i was curious is 1mm just overall " more protection" or can it cause any unintended harm with less aggressive applications

You choose the restrictors (number, sizing) based on the pump capacity/pressure. The bigger the pump, the more restriction is needed. The oil pump manufacturer will likely have recommendations. The oil control thread probably has lots of mentions, but it might take some effort to tease out the valid info. There's plenty of other mentions in other threads on here. Do some searching and see what you scare up. The search tool on here mostly works. You can also use google to search any given website directly.

[oSkylines]

48 minutes ago, GTSBoy said:

You choose the restrictors (number, sizing) based on the pump capacity/pressure. The bigger the pump, the more restriction is needed. The oil pump manufacturer will likely have recommendations. The oil control thread probably has lots of mentions, but it might take some effort to tease out the valid info. There's plenty of other mentions in other threads on here. Do some searching and see what you scare up. The search tool on here mostly works. You can also use google to search any given website directly.

Still fanning through the oil thread . Bouncing around a bit but moving from back end and have gotten back to around 50s , lots of info. Trying to take notes and not get overwhelmed at the moment . Lol

[Duncan]

Regarding restrictors, for GTR with high flow pump the information Gary posted in the first thread is still best practice....add a 1.2 mm restrictor in the open gallery and leave the factory blocked one alone. It doesn't matter whether the rear hear port is a drain or a breather, what matters is it helps the issue of breathing in high hp RBs

I use a coppermix twin in my 400kw stagea, it holds the power fine, is a worse than a single pulling away from a start (but better than any other twin/triple/quad I've tried) and is nosier than standard with foot on the clutch (but again, better than any other twin/triple/quad I've heard)

Edited September 5, 2023 by Duncan
correct restrictor size

[soviet_merlin]

1 hour ago, oSkylines said:

so straying from the Giken and leaning towards the nismo coppermix twin plate seems reasonable ? 

https://www.nengun.com/nismo/super-coppermix-twin-plate-clutch

im hoping to locate one outside of japan with slightly more reasonable shipping as nengun and justjap and the like are absolutely horrid with shipping prices to the US, But if the nismo is more drivable ill def consider that over the giken, especially ( if i can find a good location to ship from) with it being a few hundred USD less

In case you are not looking at it already, it's worth checking rhdjapan.com as well. For expensive items like that they tend to be a couple hundred dollars cheaper than nengun and justjap.

I don't know what the OS Giken is like. But I switched from an NPC heavy duty single plate clutch to the Nismo super coppermix twin plate and it made all the difference. It feels great and it's pretty much like driving a normal car. A nice one at that, not some economy shitbox with vague and wonky pedal feel. It's a bit more noisy as it produces a bit of chatter at idle and low rpm but it's not too bad. In comparison the heavy pedal feel of the single plate clutch was like driving a truck and in start-stop traffic it got old very quickly. Purely in terms of driveability I'd vouch for the Nismo twin plate.

[oSkylines]

you guys are the best , thanks for the advice these things. 

[soviet_merlin]

11 minutes ago, Duncan said:

I use a coppermix twin in my 400kw stagea, it holds the power fine, is a worse than a single pulling away from a start (but better than any other twin/triple/quad I've tried)

In what way is it different from a single for pulling away from a start?