I'm getting an RB25 soon as some of you know, and i'm not having a think about whether I should do it or not, its definitly gonna happen.... so yeah, just thought I'd say that before I start. Ok, what I would like to know is, IN A VL, I'd imagine an rb25det is better in every way over an rb30et (since its pretty much a more modern version of the engine right?) or are there some cons of having one that I should really know? I'm talking stock engines. I wanna know about things such as fuel economy, torque, lag, etc. Just things on how well the engine works with the car. Oh, and lets just assume everythings in, connected, and working, so dont tell me anything about how hard things might be when putting the engine in. I searched but couldnt find anything, so if this has been asked before, could someone link me up? thanks. Some original photos have not been recovered yet.

i always found RB25DET's to be very good off boost, thanks to the 9.0:1 compression... besides, diff gearing and a higher redline make up for the 500cc difference. love em, DOHC RB's always sound so much tougher than RB30's... hell even RB20's sound good with a nice exhaust ive heard some pretty good results with RB25's running GT35/40 turbos, fairly responsive and pretty big power too if your not happy with it, then ill happily swap ya Some original photos have not been recovered yet.

rb25 engines make rb30 engines seem very boring

b1ancardi, on a side note, where are you getting this done?? im in the process off saving for a turbo conversion but am going to stick with the rb30et, just want to know a reliable place in town that can source me an engine + gearbox and put it in plus hopefully paint my engine bay?

Integra Automotive, at the Ampol, just as you enter queanbean. They wont get the engine and gearbox for you though, or paint it. The guy that works there, Ed, has a VERY good name around town with Nissan engines. On the other hand, my brothers mate bought a workshop to start his own business about a year ago now. He's getting me the engine, and might being doing the conversion himself. Its a spray/repair shop mainly, but he'll do other things. On a side not, I've only been there once, and I noticed about 10 cars in there getting sprayed and fixed, and they were all yank tanks, with one SS Commodore, and he owns a few yank cars himself. I'll have to work out whether he will do work on VLs or not. .....by the way, do I know you? or am I thinkin of someone else?

yeah ya know me mate, went to tuggers last year, just didnt have the calais till this year, ive jsut got it looking nice and by this time next year want it going fast, i was gonna go an rb25 aswell, but ive had so many headaches with the car im sticking to the simplest approach

yeah, well that orange looks sweet as man! Mine still looks like shat, but after a couple more things, I'll start giving it a cosmetic upgrade. First on the list is the Rb25, then I still need a LSD (I have a V8 diff, with rear discs, but its only a single spinner), and then I need to do a few things to stop it scraping, because I cant even have 3 people in the car, even though it isnt that low. After that, I'll start looking around for Calais exterior parts, once I have all that, shes gonna get sprayed. I was thinking about changing the wheels to a set of 18"s, but i havent seen anyone else with the same ones I have now, and they dont look to bad. Anyways, wanna post up a pic of your beast?

yeah i went for the looks first, its bit sad though, people will think i can go fast and i have to disapoint them and its a while off till i can get the turbo conversion, not even sure how much its gonna cost, but yeah i posted a cpl of pics in the canberra thread but the link seems to have broken. if u add me on msn i'll send it to, [email removed], we need to get a cruise going on for the ACT Some original photos have not been recovered yet.

go before show Some original photos have not been recovered yet.

go an rb25det newer, ur not gonna be running 10z so it should still haul ass. and they sound hell tuff with cannons on them Some original photos have not been recovered yet.

y not jus stick the rb25 head on the rb30.....have best of both worlds

Advantages- Revs out more and is smoother, more fuel efficient and more peak power Disadvantages- Has less torque then the rb30et throughout the rev range all the way up to 4800rpm where it matches the 3litres torque The rb25det will make around 187kw stock at 6400rpm and the 30et will only make 150kw at 5600rpm, they both have around the same torque at 296nm but the difference is the rb30 makes it at 3200 while you have to rev the 25det to 4800rpm to make that torque, so with the rb25 your sacrificing some driveability for more peak power. Id take the rb25 for sure, unless it was going into my daily car and i had a family to drive around everyday, in which case id rather the low down torque, making it easier to drive off boost, in stop start situations etc.. In a race between 2 vls with a stock rb25det and a stock rb30et the 30et would prob be in front for the first 1/3 to 1/2 the race until it loses puff after 5000rpm at which point the rb25 with better breathing (twin cam) and better harmonics (smaller displacement) keeps going peaking at 187kw overtaking the 3litre in the top end... Which would you prefer? Its application specific.

Y wouldnt u just wak a rb35 head on your 30 block?

^ 25 right ? i would too but i dunno anybody in qld i can trust to build one

dont do a 25 unless u change diff gears to same as r33. mine was a laggy undriveable peice of ****. i think there 4.11 or 4.33 some one correct me. if you took off in first and changed in to second at say 30 km hour. you had absolutly no torque untill 80km, then rocketed around to 120km. it was fckted. i mean a 1950 corrola runing on 3 cyclinders and a rooted auto towing a trailer which had a motor home on in it whould of fucn blown me away until 80km.... dont even get me started if you tried this in third gear if you wanted to thrash the fcuk out off it off the line then go second it was fine dont get me wrong the enginge was in a1 nic, smooth as hell, and never let me down, keept it for 1.5years and never had an issue, apart from lack of torque. put the head on a 30 block. much nicer. and no one builds this shyt for fuel consumption. the 25 was only a liltle better than a 30et. u end up reving it harder there fore using more fuel any way

The low down torque in the rb30det gets the gt35/40 spooling nice and early. I havent driven a 25 but ive driven a stock standard 5 speed 30et and its a slug compared to the 30det. But then again you are dealing with bigger injectors / bigger plenumn and a more advanced head dohc head. The 30det is a an animal when boost comes on around about 3rd gear you start to get up to around about 10psi and with 3.9's in its hard to keep in a straight line.

Quote: Originally Posted by jbonez The low down torque in the rb30det gets the gt35/40 spooling nice and early. I havent driven a 25 but ive driven a stock standard 5 speed 30et and its a slug compared to the 30det. But then again you are dealing with bigger injectors / bigger plenumn and a more advanced head dohc head. The 30det is a an animal when boost comes on around about 3rd gear you start to get up to around about 10psi and with 3.9's in its hard to keep in a straight line. he wasnt asking about that at all. he wants to know about 30et and 25det in std form.

Quote: Originally Posted by rbfrog dont do a 25 unless u change diff gears to same as r33. mine was a laggy undriveable peice of ****. i think there 4.11 or 4.33 some one correct me. if you took off in first and changed in to second at say 30 km hour. you had absolutly no torque untill 80km, then rocketed around to 120km. it was fckted. i mean a 1950 corrola runing on 3 cyclinders and a rooted auto towing a trailer which had a motor home on in it whould of fucn blown me away until 80km.... dont even get me started if you tried this in third gear if you wanted to thrash the fcuk out off it off the line then go second it was fine dont get me wrong the enginge was in a1 nic, smooth as hell, and never let me down, keept it for 1.5years and never had an issue, apart from lack of torque. put the head on a 30 block. much nicer. and no one builds this shyt for fuel consumption. the 25 was only a liltle better than a 30et. u end up reving it harder there fore using more fuel any way agreed 100% ive had rb25 with 3.45 and 3.9 in the diff and even the 3.9's wernt enough need 4.11 to make it worth it. unbelievable ow much difference.

Thread from the dead! But yeah, stock 25+cooler+exhaust+4.11 is definitely a lot of fun, and enough to beat almost any stock street car

i wouldnt pay extra money and go to the hassle of changing blocks over... Just buy a nice standard rb25 head, manifolds, turbos Bolt that on and go from there.