Sydneykid

The problem with the short stroke 2.6, 2.7 or 2.8 litre RB's is the rod stroke ratio is far from optimal at 1.6 to 1. The RB30 has a much more desirable 1.8 to 1. This means less side load on the conrods, hence the big end bearings and the crankshaft itself. Less likely to break, last longer and make more torque at the same time. The other issue is the top end mods required to handle the rpm necessary to make the power. This requires exotic (expensive to buy and maintain) titanium valves, retainers, collets, valve springs, hardened valve seats etc. This adds considerably to the cost. Most of which can be avoided with a 3 litre as it is simply not necessary to rev it so high to achieve the same power. A further issue is gearing, if you are going to run 14,000 rpm then you need to carefully consider the gearbox and diff ratios. Running 4.1 to 1 (standard) diff ratios is not an option when optimising 1/4 times and TS's with that sort of power band. As for power handling capacity, we have an RB31DET that made 930 bhp on the engine dyno. It had a std RB30 block & crank with forged rods and pistons and a worked RB26 top end. But there is no need to rev it past 9,500 rpm, so stainless valves are OK, normal spring steel valve springs, alloy retainers, standard collets etc. This is big saving over the exotics in intial purchase cost, plus they won't need servicing every 2,000 k's. If the RB26N1 block increases this by ~1,000 rpm (not unlikely), that would endow the 3.1 litre with the same power capacity at 10,500 rpm as a 2.6 litre at 12,500 rpm. You have to compare the cost of the whole package, as it is obvious that there is far more to it than simply comparing a 2.6/2.7/2.8 litre bottom end cost with a 3.0/3.1 litre bottom end cost. PS, a billet crank girdle extending out to the sump mounts would increase the RB26 block rigidity considerably and thus remove some of the distortion loadings on the crank at even higher rpm's. PS2; Hi Greg, nice to see that seed I sowed has grown.

R32's always look so good with R34 wheels :Pimp2:

You can't use an R32GTST ECU in an R33GTST, no VVT for a start, plus the pin outs are totally different. I should point out that in my opinion any ECU tuning not done on line (ie; off the shelf chip) is a GUESS, and every engine is different. I can't see how an FMIC will make it worse. If it lowers the inlet air temps, you may be able to run lower boost (decrease the airflow) and make the same (or maybe even more) power. Less airflow would mean the standard ECU would resort to a lower (or non existant) R&R strategy. The only time an FMIC would make it worse is if you choose to allow the lower resistance to increase the boost. But that is your choice, not the FMIC's.

I have no idea, I never use plain bearing turbos:cheers:

The R32 Tomei kit comes with tricker box to stop the HICAS ECU turning on the light. PS; I removed the bulb.

Well I have seen a 25 rwkw increase and 400 rpm earlier boost build from an R32GTR running R34GTR (ball bearing) N1 turbos. That's with no boost increase, in fact there was a boost decrease as it obviously removed a restriction. And no extensivel re-tuning, just a couple of minor fuel and ignition timing changes. More advance as the boost was lower. This improved the response measurably, which is a welcome bonus.

The Tomei kit has 2 thick high tensile locking rings that bolt onto each end of the rack and stop it from moving. There is no "force" involved here, unless doing up the standard retainers is "force". Not all Skylines come with HICAS, those that don't, have no rear rack, the steering arms bolt to the rear subframe. This is basically the same as the solid rack replacements you can buy. Again there is no "force" involved. I have removed HICAS from 10 or so Skylines and never had a problem with any of them, one was 5 years and 70,000 k's ago.

Too low is slow. By removing the inner guards panels you have noticeably increased the aerodynamic drag, thereby lowered the top speed, reduced the acceleration rate and increased the fuel consumption. Shall I get into how much power you have lost in excessive drive shaft angles? Nah, it's not realy necessary because everyone knows that:cheers:

OK Jamie, I am glad we flushed out the full story. Are those front pipes you have titanium? If so, you won't have any trouble getting your money back. I think you really need to do the numbers, something like this; Paid for current engine pipes $500 HKS or CES short dumps $700 Total $1200 Sell current engine pipes $200 Loss $300 Trust turbo back with long split dumps $1100 Total $1400 They are most certainly worth the extra $200. Stick your real numbers in the above calcs, then you can make an educated decision.

The race R32GTST was 1295 kgs when we got it, it is now a little under 1200 kgs, with some stuff added and some more stuff removed.

But I have 3 and it will only let me vote once :confused:

Better fuel consumption, yes a little bit Better power, yes a fair bit Better reliability, at that / power level, yes a lot Worth the extra cost, yes in my case But it's your money, not mine:cheers:

The Stagea has no dips in its power curve, I tuned them out with the DFA and the IEBC. It drives just as nice as standard, in fact maybe even slightly better. It is a very safe tune, but I compromised on the power by doing so. The DFA and the IEBC are the best bang for buck engine mod I have ever done on a Skyline (Stagea in my case). So I would not be arguing against them as a value for money choice.

"Sideways", yep I have certainly done that. "Hitting walls"., yep I have done that. "On fire", I think you are much better at that than me But I have done "roll over" only once but it was a good one, 7 times, 4 side to side and 3 end for end. Great ride, but don't want to do it again, I can still close my eyes and see sky, track, sky, track, sky, track, when will it stop.

#1. Very good question, I have compromiseed a lot of performance to make sure the Stagea engine is safe. After all it is the tow car and I need it to get to race meetings, so there are arguments that it has to be more reliable than the race car. #2. Yep, good improvements from the DFA and truly great value for money. With the full tuning ability of the Power FC, I most certainly could have done quite a bit better, more power, more response and better fuel consumption The bottom line is if it was a manual, it would have a Power FC in it.

Why are you so attached to that set of engine pipes? You are compromising the whole system because of it. I would sell them and buy the CES turbo to cat system, if money is the reason you want to keep them. If money is not an issue go the Trust, they are a true work of art. Either way I can asure you that the results will be worth it.

Here is one I prepared earlier; Hi guys, here is an example of 4 intercooler setups and pipework we have actually used; 1. R33 GTST Standard Intercooler and standard R32 GTST pipework 150 rwkw = 27 lbs of air per min @ 13 litres of i/c & pipework 2. Supra Intercooler and matching 63mm pipework 180 rwkw = 30 lbs of air per min @ 15 litres of i/c & pipework 3. Standard GTR GTR and 63/75mm pipework 250 rwkw = 40 lbs of air per min @ 21 litres of i/c & pipework 4. Greddy 600 X 300 X 115 and 80 mm pipework 400 rwkw = 60 lbs of air per min @ 28 litres of i/c & pipework If you look at the numbers you can see that the rate of air flow and the volume of I/C and pipework have a fixed relationship (27 = 13 , 30 = 15 , 40 = 21 , 60 = 28). This is not an accident, I designed it that way. The reason is I wanted to keep the throttle response as close what it was when the car had 150 rwkw, because I though that was very nice response. The theory I followed was, the more power the engine produces the more air it needs. Thus if I keep the increase in the volume of air inside the inlet system in the same proportion as the power increase, then the throttle response should stay the same. This is based on the engine using the air in the same time frame. So when people say they fitted a FMIC and have not noticed any less throttle response, my response would be, that is what I would expect. As long as they went from 150 rwkw to 180 rwkw. On the other hand, if there was no power increase then it would be simply physically impossible for there to be no decrease in throttle response. The problem of poor throttle response arrises when you have a 220 rwkw engine with a 28 litre inlet system. This is something I see way to often. Hope it helps:cheers:

The PCV valve opens under vacuum (ie; when the throttle is closed) so there is PLENTY of sucking making up for small holes. Back to the question at hand, as long as you run the cam covers linking hose there is no problem with only running one vent hose to the catch can.

What model Power FC is this?

Ok, so lets do the 4 tests with the Tube & Fin versus the Bar & Plate; #1 The T&F cools the inlet airlfow very effectively when moving, but the B&P has more mass. So it is better at taking heat out of the inlet air instantly. That's why T&F are used on circuit race cars and B&P are used on drag cars. #2 The T&F is a clear winner in this one as its design allows much freer movement of the ambient air through the intercooler core to the radiator. Obviously a side mount intercooler has none of this problem. #3 Depending on design, the B&P can be a little better in this test, but at the price of loosing some on the move cooling efficiency. Overall not a lot of difference, but some designs are much worse than others. #4 B&P tends to have more internal volume for the same external dimensions, worth keeping in mind if throttle response is important. #5 (new one = price) B&P tends to be a little cheaper as the extrusion process is easier and faster. Hope that was of some help:cheers:

Some of my previous posts on BOV's; --------------------------------------------------------------------------------------------- Oh no, the old "BOV's don't do anything" line ............. Why did Nissan fit them? Why did the early turbo engines (someone used the NICS and RB30ET examples) not use them and had recommended turbo servicing at 60,000 ks'? Why do the later Nissan engines have recommended turbo servicing at 120,000 k's? Does anyone really think that Nissan wasted money on BOV's, fitting something that wasn't necessary? They would have saved millions of dollars over the life of R32/33/34 and S13/14/15 and Stagea and ............you get the drift. Does any out there really believe that comparing race cars with no BOV's and road cars is realistic? Give me a break, we service turbos every 2,000 ks' of racing. Personally I don't want to be doing that on my road car. With a boost gauge plumbed to the comprressor housing you can easily see what happens to the pressure at the compressor when you close the throttle without a BOV, double the set boost limit is not unusual. Does any one really think that that is somehow good for your turbo? Everyone has heard the turbo flutter noise when the throttle is closed and no BOV is fitted and noise = vibration at the tubine blades. Does any one really think that that is somehow good for your turbo? As for slowing the rpm versus reversing the flow. On the engine dyno I have seen large amounts of air flow out of the compressor inlet on throttle close. That air is coming from somwehere and it has to get past the compressor blades to get out. So I have no problem with the thought that the compressor blades stop or turn backwards. Even if they only slow rapidly, does any one really think that that is somehow good for your turbo? ------------------------------------------------------------------------------------------- The idea of a BOV is to prevent the air from reversing direction when the throttle is closed. This has 2 effects; 1. It prevents the compressor being suddenly stopped (or run backwards) when the air rushes back the wrong way. 2. It keeps the air (in the intercooler and pipework) moving in the right direction ie; towards the engine. So it would appear to me that #1 would be satisfied no matter where the BOV is located. But #2 is best satisfied by having the BOV as close to the throttle body as possible. That way none of the air is going the wrong way. This would mean better throttle response when the throttle is re-opened. --------------------------------------------------------------------------------------------- So by not running a BOV or by excessivley tightening it, you are shortening the life of your turbo and you are decreasing the performance of your engine. It seems like a dumb idea to me.

What I can tell you about RB valve train; The RB20DET valves are not the same as any other RB. The combustion chambers are too small for RB25/26 sized valves. The RB26DETT valve train has solid followers, RB20& RB25 have hydraulics. So you can't use bit out of one in the other. You have to swap the whole lot over. This is of no use to you as the valves won't fit anyway. You can use RB26DETT valve springs in an RB20DET but you have to modify the spring seats in the cylinder head and the retainers. You also have to use shims to achieve the right seat pressure. We always use genuine Nissan valve seat inserts, the part numbers are on FAST. We find it is cheaper to throw bad RB20DET cylinder heads away and start with a good one. It is cheaper to buy a good used cylinder head and refurbish it, than buying the new parts from Nissan and then spending hours on it. Hope that is of some small help:cheers:

All the wiring harness plugs (for the MAP sensor and the solenoid) on the Boost Control Kit (BCK) go back to the Power FC itself.