Quote: Originally Posted by MonstaS4 Hasn't really been a problem directly related to the conversion i guess. I still had the problem (only on 30+ days) when the single cammer was in. I'm using a 16" thermo with the shroud. I think the fan might be too close to the radiator though. Even with the shroud, it must be only sucking air through the area of the fan, not the whole radiator. I reckon if was back towards the engine in the same spot the clutch fan would be in, it would be better. But....it still struggles to hold the guage at or below 1/2 when on the highway, which suggests its not getting enough airflow. The cooler and a/c condensor in front of the rad can't be helping. I've seen VL's with a black plastic thingy under the radiator. Is this some sort of scoop? cos mine don't have it. Sorry carcrazy....bit off topic! I have seen this problem time after time even more so on the dyno, the fix is remove your thermo fan and put the standard clutch fan back on. The thermo fan is not as efficient as the standard fan. People always say that the standard fan robs engine power? work out the extra drag that the alternator creates by sucking 25 to 30 amps of current with your thermofan.

Quote: Originally Posted by GTRVL I have seen this problem time after time even more so on the dyno, the fix is remove your thermo fan and put the standard clutch fan back on. The thermo fan is not as efficient as the standard fan. People always say that the standard fan robs engine power? work out the extra drag that the alternator creates by sucking 25 to 30 amps of current with your thermofan. Good point. Is there a better clutch fan avaliable?, i.e. an RB25 or 26, that may have more blades or is a bigger diameter, maybe the hub operates at different temp ranges. Anyone played with the RB fans to see what the differences are?.

I have to disagree, while an electric fan draws alot of power it does it evenly over the rev range. A clutch fan is made to cool your engine at low to medimum revs so at high revs places alot more drag on the engine than an electric fan ever would. Then there's the controlability of electric. Still a clutch fan is more efficent, no doubt but would any1 ever notice a diffference in fuel economy??? On a dyno grab a dirty big 240V fan and stick in front of the car, easy fixed. If you're overheating with a 16" thermo with normal driving there's something else wrong.

fix your radiator

Radiator is brand new, thermostat is brand new. ATM it's not a problem, especially here in Ballarat. As i said it's only a problem on 30+ days, so when the weather warms up again i'll throw a clutch fan back on it. I wouldn't think an electric fan drawing 30A would place any extra mechanical load on the engine. The rotor in the alternator still spins exactly as it would if it were only drawing 1A.

In my VL I have fitted a 17 inch diameter electric fan to cool the radiator with my RB30DE motor and it only needs the fan usually at idle or when crawling around town,or sometimes up a hill. Other than that,when cruising at 80 - 100 KPH the temp gauge sits just above the second mark so the fan doesn't do anything at those speeds. I am not sure what power mine is putting out but I have heard of someone who has fitted one of these to his R33 Skyline using the standard ECU like I have done,he is getting 126RWKW (173 FWKW) out of it. The 300 odd kilowatt one from New Zealand would have major work done to it (i.e. cams,porting,etc),the maximum horsepower figures I have heard coming out of a BMW M3 is 250 FWKW,it has a 3 litre DOHC motor as well. There is a Skyline in Japan which is using an RB26DETT head and multiple throttle bodies on an RB30 block (imported back to Japan),its power output is 224 FWKW. Mine goes pretty hard but relies on revs to generate its power,if I can do 110 KPH in second on a flat,it is also possible to do it on a steep hill whereas the old RB30E would die regardless of gears & revs on a hill. I find if I get the revs right in first,I will be pinned to my seat when the car is hammered,I virtually have to floor it as soon as the clutch is disengaged to do that or else the revs will just build up over time till they hit their peak,this is when the power is felt, which is usually 80 KPH in first and 100 - 120 KPH in second.

on a mate of mines car we left off the wire to his thermo fan. he drove all day in summer heat and it didnt even heat up!. we both use big 4 row radiators

I got 2x 16" davies on my skyline and its been great. best thing I ever did was **** off the clutch fan.

Quote: Originally Posted by twinvl I was prob 1 of the first to start building a DET and i still haven't finished.... Not worth it yet! It's still in NA form atm, and the biggest problem i've come across is trying to save some $$$ and use the standard RB30E management, or a timing issue. It just doesn't want to play the game (not enough power and crap idle) so it's been sitting for a few months now waiting for an Autronic which is coming very shortly! And turbos fitted shortly after that. I've had no big problems that weren't expected. The timing belt has been fine aswell as the block bronsing to seal the water gallery to the head. Most of the work has gone into the custom inlet manifold which has made things difficult from an assembly point of view. So far it hasn't cost that much, a quick add up to $2500 inc 2 rb20 turbos and the Rb25de engine. The first time i ever saw this conversion was 10 years ago when peter hill built his 4wd calais useing rb30 block / rb26 head i think he may have been the first?

Quote: Originally Posted by Krieger i disagree, it is the one of the earlier examples of VVT, so obviously it's not going to be as advanced as the VVT systems that are coming out of the factories now. but anyway, it's there on the head in the first place, it's just up to the owner to choose if he's gonna use it or not. -jimmy Good point Krieger, i have tuned a few of these engine on Autronic which will control the VCT, with stock cams you can gain a little of bottom end / midrange torque but not much of a gain at the top end, if anything switching the cam advance on at high rpm tends to cause detonation, but to a keen engine tuner if you can gain kw's for the customer by switching on a soleniod then im all for it. 87calais is correct moving the cam timing on any engine simply moves the power band this is the case with standard or modified cams although lot more benifial and easier with twin cams. Advancing the cams will give bottom end to midrange power retarding will give better top end power. Camshaft selection is the one thing that will make or break the power your engine will produce, i have seen some engines make less power on so called performance cams than on the stock cams, this is one area that requires the advice of an expert not just what you see in a performance part catalogue.

The VL's have 7 blades and have a steeper pitch. The RB20/25/26DET's have 8 blades and have a flatter pitch. The steeper the pitch the more air a fan will push/suck. The less blades it has the more air it will push/suck. The VL fan sucks/pushes more air and is quite a bit louder. :P

Quote: Originally Posted by GTRVL The first time i ever saw this conversion was 10 years ago when peter hill built his 4wd calais useing rb30 block / rb26 head i think he may have been the first? Yeah i'd say so... I ment 1 of the first on the forum... can't you read my mind Just not alot of info about it then, had to work out the vvt for myself, ect. Quote: Originally Posted by MonstaS4 Radiator is brand new, thermostat is brand new. ATM it's not a problem, especially here in Ballarat. As i said it's only a problem on 30+ days, so when the weather warms up again i'll throw a clutch fan back on it. I wouldn't think an electric fan drawing 30A would place any extra mechanical load on the engine. The rotor in the alternator still spins exactly as it would if it were only drawing 1A. Just on the alternator load thing, if u draw more current from it, it puts more load on the engine regaurdless of speed, only that as it speeds up the torque needed to drive it lessens so it draws the same 'power' from the engine. Huston, we still have a problem... Water pump? Flow blockage?? Some original photos have not been recovered yet.

Water pump is brand new, and the block was dipped before the engine was built-up 6 months ago. I'm sure it's lack of air flow due to the cooler and condensor in front of the radiator. Not trying to start an argument, but how can an increase in current draw place more load on the engine. The rotor is inducing a current into the stator and it's output is proportional to rpm. The rotor is still doing the same amount of work if the alternators output is 70A or 1A. The regulator is electricly controlling how much of this work is converted into electrical energy.

ever so simple currently i have the two major part block 150 gtr head(intake turbos everything) 1600 timing belt 100 head gasket 100 gtr wiring oom 300 already had the computer ect just need to get a clutch plate and a 5 speed then ill wack it al together im not rebuilding the bottom end we have two mates running stock bottom ends for the last year with 280rwkw+ and they are fine pete

Quote: Originally Posted by MonstaS4 Water pump is brand new, and the block was dipped before the engine was built-up 6 months ago. I'm sure it's lack of air flow due to the cooler and condensor in front of the radiator. Not trying to start an argument, but how can an increase in current draw place more load on the engine. The rotor is inducing a current into the stator and it's output is proportional to rpm. The rotor is still doing the same amount of work if the alternators output is 70A or 1A. The regulator is electricly controlling how much of this work is converted into electrical energy. Yeah fair enough with an IC and condenser blocking flow your prob right, so that your prob. When more current is drawn from the alternator it becomes harder for the rotor to break the magnetic field created by the stator, placing more load on the engine. It's the same but oppisite as and electric motor. The more load placed on the motor, the more current it draws. As the rpm increases, the voltage increases so the regulator decreases the stators field to decrease the voltage back to 14.4V So becomes easier to turn with the same current draw but since it's spinning faster it's using the same power from the engine. You can do the experiment if u want, loosen your alternator belt to the point where it just doesn't slip at above idle, then turn on you headlights! This is way off topic.........

i did rb30de conversion about 18 mths ago and about 30000kms ago has rb25de r33 series 1 head xf t/b bored to 68mm used the rb25de pistons ( 10.5 - compression ) reflanged set of rb30e extractors rb25det injectors ( 370 cc ) malpassi fuel regulator mines ecu meant for a rb25det( which is a non adjustable ecu ) apexi safc 2. vvt timing is hooked up great fuel consumption idles smooth at 650rpm revs to 7000 + best 1/4 mile time 14.7 @ 93 mph ( with 3.7 ratio non lsd ) will be fitting the locked 4.11 diff soon also making up a twin t/b , twin afm inlet setup and all this is in a very stock looking 1987 skyline station wagon

I have to say after completing the RB30DET conversion and driving it for a few months. I can say, bloody torquey.... From idle right through to 6K It drives like a modern engine should, stacks of torque and very linear power curve, crisp throttle response. Very nice engine to drive, i say. Im still running the standard ecu, standard cams and VG30DET turbo, so its much like it would have come from factory if it was built by Nissan i guess. Stuck at running 7 psi at the moment, (very difficult to get around the cuts and limits in the stock ecu) feels as though its got just under 200rwkw comparing to my calais in outright speed. But the midrange feels as though it has an extra 20-30kw everywhere in the revrange compared the to RB30ET engine with similar max power figure. So the average power is way more then the RB30ET, even though the maximum power is not a huge number, on my particular engine at the moment.

I am currently doing this conversion at the moment, and seeing as everyone here has done it I was going to say what I am doing and if you can help me or point me in a better direction it would be much appreciated. The block is getting machined now, Its just going to get freshened up with a NA ACL race series rebuild kit with new rod bolts and prepped rods. The head is also getting done, its been stripped pressure tested and its all good . Its an R33 RB25DET head with VCT which is still going to be used. I am going with standard inlet manifolds and Ive got 550CC injectors. Unsure what ECU to use, and I am also unsure of turbos, I was thinking either GT35R with a 1.06 exhaust or standard R32 GTR turbos. I am leaning towards the GT35R though. Could someone tell me if this motor could possibly collide pistons with valves? ie is it going to be an interference motor? Thanks Edward Some original photos have not been recovered yet.

i used the same head and pistons as you, and mine is non-interference. however it hasn't run yet, and as such the lifters may pump up a bit. this COULD make it interference, but there's no way of knowing at the moment. i suspect it will be OK. i would use a GT35R 1.06 rear, spot on. the other option is a GT35/40 with 1.06 rear and an internal gate, either of these turbos would be perfect for this engine. as for the ECU - it's hard to go past the Apexi powerFC. plugs straight into the standard loom and uses all original sensors for that factory look. you will need a big AFM - either a Q45 or a Z32 AFM depending on what power you're chasing. it won't break the budget though, and has all the features you need. even comes with a pre-programmed base map to get it running straight away with little tuning required.

thats nice too know would I be better getting an R33 RB25DET PowerFC obviously? Some original photos have not been recovered yet.