Jump to content
SAU Community

Recommended Posts

With your different compressor it would act differently to mine and come on later but stronger. A friend of mine had the 750HP XTR made for his R32 GTR. My back ribs hurt after a ride in his car. Nothing until 4-4.5k and then bbwwooooossssshh.................RB symphony. Gotta love the screamer pipe. lol

Hi guys, extra 0.15 bar to make up for 0.5 lower compression ratio????

That sounds about the amount you would need to get the same combustion pressure, I have never tried it though. But I don't think that is the point, I believe the issue is how much longer does it take to get to the same boost, and then how much longer does it take to get the extra 2.2 psi.

You may find that the average horsepower is lower because you have to use that part of the rpm range. This is particularly noticeable after an upchange, where you get a hesitation in the acceleration while the rpm and thus boost gets built up again. Do this 3 times in 1/4 run and you have a big difference in ET and TS. Let alone in a circuit race car where you do 20 gearchanges per lap over 20 laps, the difference is half the length of the straight.

I think it would be interesting to look at the exhaust gas production (volume and velocity) of the two compression ratios, that may actually tell you more about the costs and benefits.

But that calculation makes my brain hurt, so time to stop.

I'm curious what does it actually cost to get an old VL block cleaned up inside and out and how clean do the water and oil channels actually come up.

I got a new series 2 VL block off Nick and at $450 it seems pretty good value and of course gets you off to a good start.

ps got an old block for the crankshaft etc cost $50

riceline, are u planning on using this thread as ur own personal diary?, or going to offer some info at some point.

As for the heads,

If it was not for the cam's on the 25 you would not tell the difference!

you'd have to be lame not to tell the difference between a sohc head and the dohc head.

I have got the motor out of the car... What i want to know does anybody know a way to get the harmonic balancer and clutch/flywheel assembly off the motor, The gearbox is still in the car. I'm thinking im going to have to get a motor shop to do it.

is it possible to machine the rb25det pistons to acheive 9:1cr without weakening it it anyway?

or can the block be machined a bit?

it seems worthwhile to have 9:1cr, seeing as the rb25det has this cr.

OMG i thought this thread would never finish!

I am very impressed with all the helpful information supplied by all!

I am from the calaisturbo forums actually and i am considering the DOHC and turbo conversion to the series II n/a block.

Ive just got 2 questions;

1.

The thing that worries me the most is the VCT RB25de head... and in the DIY RB30det pdf file, it says

'The RB25de head from the R32 GTS non-turbo bolts straight up to the RB30e bottom end.' Just to clarify this, does this mean that NO drilling or filling or welding or whatever has to take place to get the head and block to mate well? So, if i used a R32 GTS non-turbo head, it will bolt straight to the RB30e without modification? Because if this is true, i am going out and buying one this weekend! :-)

2.

To get a turbo and RB25de head to work well for a daily street car, which aftermarket (stock?) ECU will handle all this? I havent read into it too much but cost is always a factor, so what do you guys recommend?

Thanx again and well done on an informative and llllooooonnnnggg thread ;-)

The R32 GTS RB25DE head is a straight bolt up. You can use either the headgasket from the R32 GTS RB25DE VRS kit that costs $275 from Nissan (All top end gaskets, rocker cover gaskets etc) OR you can buy a RB30E headgasket for around $80 and use that.

There is no drilling or filling required.

Because you have a VL the only problem with running the engine is the CAS. You will either have to adapt the wiring loom/ecu from a R32 GTS and get it chipped or fit an aftermarket ecu with the required wiring adapted to allow the CAS to work correctly.

I went with the R32 RB25DE head as it is an easy bolt up in to the R32 GTS. If I were to go the R33 RB25DE/T head then I would have to frig around with an ecu that can handle the VCT, fill in holes and drill a new oil supply for the VCT.

The port size & valve size between the R32 RB25 & R33 RB25 heads are the same. The R33 RB25 appears to look bigger however it isn't as the R33 RB25 ports have a slightly different more open looking design around where the injectors sit. The ports are not bigger though. Use the RB25DE inlet manifold & plenum. The RB25DE injectors are the same as the RB20DET injectors.. 270cc's or is it 320cc's from memory. I think the R33's are 370cc's.

You would have to some how get the wiring sorted so that the CAS will operate as the CAS is what keeps track of where the crank is so that it can fire the required coil/plug. The VL's use the old distrubutor which is a mechanical CAS, in other words the VL/T ECU hasn't got provision to fire coils etc as that is what the distrubutor kind of replaces. It spins with with the crank and sparks the required plug when the rotor button touches the bits in the dizzy cap.

That is where the problem lies. I'm sure the VL turbo calais boys would know the easiest cheapest way to get around the problem.

Hey guys motor is geting there very nicely.. just need to know about the timing belt.. I have the belt (dayco 94407) and have relocated the tenisoner stud... just need to know where the timing marks on the belt would be? and how many teeth from the bottom timing mark should i be putting the belt on at?

Just a few extra questions.

I am looking at geting new vaccume lines. Would you guys recommend it?

I know that the standard radiator will cope with the load but i also know that Try09 runs a VL radiator Is it much bigger than the skyline one? If it is im going to get one and give my skyline one to a mate with a 180..

It looks like my engine build won't be ready in time for me to put in my car and have some fun. I head over seas in March for an unknown length of time so i'll probably sell my skyline (and all associated turbo equipment/mods). But i'll keep the engine and hopefully put it in a GTR when i get back :rofl:

No point wasting the quality parts as well as time and effort put into the build. I'll just store it till i get home and unleash the fury then!

gijor33

Thats a shame man that you wont get to play with your new toy for a while. Be sure to keep on this fourm when you are gone just to see how others are going and what not.. Ill be sure to smoke up the rear's when out at willobank for you :P

I just also want to ask a few questions.. I know that I have asked them on the last page.. but not many people read back through the thread.

I just need to know about the timing belt.. I have the belt (dayco 94407) and have relocated the tenisoner stud... just need to know where the timing marks on the belt would be? and how many teeth from the bottom timing mark should i be putting the belt on at?

I am looking at geting new vaccume lines. Would you guys recommend it?

I know that the standard radiator will cope with the load but i also know that Try09 runs a VL radiator. Is it much bigger than the skyline one?

take it easy guys.

No timing marks on belt as far as I know, marks are on the top wheel with a reference mark on the front of the head just above it. re vaccume lines....depends on the condition of the old ones. Re radiator.... I don't know I would assume that as the RB25 developes more power in stock form it's radiator would be bigger capacity..... but don't quote me on that .

Hi 51jay,

I would assume the oppisite as the RB30 motor has a bigger displacment than the RB25. Bigger displacement = more heat.

If your worried about cooling, this is what im going to be running with my RB30/25:

http://www.are.com.au/Rad/radiator_options.htm

I've got a R33 Radiator shroud on my R32 GTS-T radiator, they appear to look the same size.

The RB30 VL radiator is massive compared to the Line radiators, I doubt it would fit.

With regards to the RB's I believe

displacement = more heat
is a fallacy.

VVT and not using it...

If you don't want to use VVT (cam gear, or just don't want to hook it up) do you need to leave the big thing on the front of it? because when i undid the 4 little bolts oil came out, then when i undid the big bolt in it more came out. So i presume that if you decide to leave that bit off then you are going to have oil leaking out. So if you have a VVT head, what do you need to do if you don't want to use the VVT?

We've discussed how to hook it up, but we've never discussed how to disable it.

And also what head bolts do you use? do the normal RB25 head bolts fit?

you have to have a line to the head as the oil not only runs the VVT it also lubes up the cam bearing so your kinda stuck with it.. if you dont want to run it just pull the fuse i belive..

as for the head bolts a have the rb25 ones in and they work fine

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • My thing I'd be doing, is pulling it out, and just getting the tune cleaned up for now. Before that even happens, checking over everything, like vac hoses, fuel hoses, etc. No point dropping thousands on sensors if the moment you start it back up all the oil leaks out, or it has massive vacuum leaks etc.   But really, to know what to do, depends on what your use case is. Hard core track car? Throw most sensors available at it. Street car, I'd probably just run oil pressure, oil temps, water pressure, water temp, probably fuel pressure too. I don't know exactly what the Link can handle and do with those though. And if it's mainly just to cruise the streets, rather than mountain runs, you can probably skip most of the above if you've already got them in as gauges and warning lights.   PS, inb4 "sell it and buy a modern sportscar"
    • Keen to see the turbosmart data, to date I've only seen negative things in terms of response for them. Very small sample size though.     Hawkins is a big advocate in his videos of the larger rear housings. I managed to make similar power with a lower spec motor on the smaller .8 rear, keeping decentish spool.  The people he works with now are big power cars compared to mine though, mine really is setup to drive around and enjoy.  I don't have any back pressure monitoring though, so couldn't say if its good or bad on my car, just that it does what I want it to do.   Future I want a higher compression more cubes motor to give a bit more bottom end and hopefully the new g35-1150 gets me to the 850 rear comfortably.  But maybe I won't due to exhaust back pressure.
    • No, I refuse to buy their cheap ass crap! I do need to order a bunch of different nuts/bolts to refill my nut/bolt wall though. Maybe you could go for a walk through Bunnings for me? (Or send me some stuff from your work? )   I really struggle to work out how the US standardised to Metric in what the 70s or 80s, and yet, half a century later, there's been little done to actually bring it into fruition. It truly baffles me    On the whole Fastenal thing, I went reading their site (My god they sell a lot of varied stuff!), and it seems like it really depends what store you're near if you can walk in and just grab a few small things, or if that branch is primarily distribution with only a small window of "counter time" available (if at all). That definitely makes it harder, as move locations and it drastically changes your ability for success   For things like your M6x1.0, if you want to work on your own Skyline, and you also have a "home workshop" I'd recommend setting yourself up a small Nut/Bolt wall/section. It doesn't even need to be big at all. Most things depending on the diameter, will be a specific pitch, like the M6x1, M5x0.7 etc. Bigger bolts is mostly 1.5, except for a small number of things and that will come down to torque. From memory bolts for the brake calipers (and other things that need a lot of torque) will end up being a 1.25mm pitch. Save up a few dollars, and order a range of nuts/bolts. If you want to minimise cost a little, buy something like M6 x 40, and M6x70mm (1mm pitch) in both. In addition, buy yourself an M6x1mm thread chaser. That way you have long bolts that you can cut down to size, and then chase the threads out. Funnily enough, I find what I'd pay here for ordering 5 bolts, I can pay about 50% more and you'll get 100 of them.   If that doesn't quite work out due to space / ability to buy plenty up front, then each time you need some bolts, order 100 of what ever you're getting. Put them in clearly marked containers. Over a few years, you'll acquire plenty of different sizes, and will end up ordering less and less. And the cost for 100 bolts won't be much more than you paid for your 5 you needed to order anyway  Just takes a little planning ahead, by investigating what nuts/bolts you'll need, and ordering them before doing the job.     Edit: If it's also primarily for working on just the Skyline, for some reason my brain is screaming that at some point, either Nissan, Nismo, (Or possibly a third party) was selling a "kit" of every nut and bolt in a Skyline, purely for people restoring/rebuilding. It'd likely be quite expensive, but would give you every/any nut/bolt you need for stock/factory things. I'm not sure if it's still available, or even if it actually fully came to market, it's just something niggling in the back of my brain that you could look into further if that sort of thing interested you? (It might have been for the R32 GTR or something specifically too, and not just any Skyline)
    • 90lb/min @ 20psi is wonderful, not so much of a problem with the G35-1050's compressor efficiency (aside from how bad they roll back at higher pressure ratios).  The issue is more to do with the turbine's flow, which is why I'm not sold on going an even higher flowing compressor with the same turbine.  I'd say go back over Motive DVD's testing of the G35 1050 and Hawkins's comments regarding exhaust back pressure issues with it, I'd need to go back but I have in my head he went to the biggest hotside and ended up sacrificing a lot of spool (so it ended up behaving like a bigger turbo) and still had EMAP issues.  I've heard various other experiences along the lines of that. At this stage at least I rate all I've seen about Xonas (for transparency I've not used one directly, but I have spoke plenty with people who have) to have low exhaust restriction for the response they offer for any given setup - basically they allow the engine to breathe, which is good for the engine and makes making power a lot easier.  You arguably don't have to even push quite the same amount of airflow through an engine to make the same power if you don't have the bum plugged up with exhaust gas struggling to escape the engine due to an underflowing turbine.   In terms of reliability, to be fair I've had great luck with Garrett turbos as well - my GT3076R lasted forever, then I sold it and the next owner had no issues, then that car got sold and it was still going strong last I ever heard about it.  The trick is with the old GT-series turbos the compressors etc were no way near as efficient as what we have these days, it was almost hard to push them into severe overspeed situations without having a boost leak or something - and that is what often starts the failure situation.    In terms of your G35 I'm pretty sure you're running yours within sensible limits, something people with Xonas and Precision turbos aren't often so inclined to do.  The "compressor maps" are "Joe blogs ran 45psi through his 6466 so I can do the same" and built their setup to send it to the moon.  I've seen EMAP and compressor speed data where people have actually set that stuff up on Precisions and Xonas which have been run hard and the comp speed numbers are very very exciting at times - like I've seen 76mm Precisions run at rpm that you ideally shouldn't run a G35 1050 lol.   I know people who have run G-series Garretts hard and hard a failure, then replaced them with Pulsar turbos as a cheap "get it going" stop gap with the intent of doing a proper upgrade when THAT fails... and are still running the same thing.   Like anything, ymmv and it's not always to do with the quality or trustworthiness of said product. I've been provided with a bunch of compressor maps for Turbosmart turbos and will update my list based off that, they could prove to interesting reading and an interesting alternative as well.
    • Just cage it, call it a race car, and then fall in love with the chirp chirps through pit area!   Also, this is coming from someone with a completely locked diff...
×
×
  • Create New...