SLIMVLT Posted July 23, 2006 Share Posted July 23, 2006 now ive beer reading this thread for about 3 months and looking at what u have been doing. i have a vlt with 250 rwkw just a rb30et and a r31 with a rb25de 119.7rwkw i did all the work my self.i have another rb25de coming from just jap and was wondering ifd its worth the hastle of converting to dohc for my vl. like how easy is it to make lotsa power cos i would want more than 300 rwkw due to the power my curent setup. now is is posible with na cams? also if i replace the cams do i just have to replace just the shims.what lifts do u get and what kind of overlap do u have with the tommi camshafts. my vlt is fairly lumpy and i like the sound of a engine that has afair duration camshafts, i know the vvt wil be a issue but is there anyway around this. Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2350394 Share on other sites More sharing options...
kastin Posted July 26, 2006 Share Posted July 26, 2006 (edited) Sydney Kid What exhaust houseing size on the gt35/40 did you use in the following setup? and have u got any dyno pics? Cheers Jon [There were very few "brand" name parts used; Standard RB30 block, crank, water pump, oil pump and balancer Balanced up & down and round & round bits O'ringed block and double annealed copper head gasket ACL Race Series pistons, rings and bearings Pistons were ceramic coated on the crowns and oil retention coated on the skirts Argo I beam rods with ARP rod bolts Std VL RB30 Commondoor gaskets and seals Fabricated sump with wings and baffles ARP studs for cylinder head and main bearings Std RB26 Camshafts, valves, retainers and followers Performance brand valve springs Adj camshaft pulleys (no name brand, early Jun style) Gates cambelt Ported head with polished and matched combustion chambers GT35R on a no name high mount manifold with a no name (HKS copy) wastegate 850 cc Cosmo injectors Bosch 044 fuel pump Nismo regulator on the standard fuel rail Power FC PWR intercooler Q45 AFM Run in on the dyno for around 1 hour all up, change oil and filter and get into it. Calcs.......... 632 bhp = 472 kw less ~60 kw (2wd) = 412 rwkw The average power from 4,000 rpm to 7,000 rpm is massive and it's not straining at all. A/F ratios are not over 12 to 1 anywhere and the knock is less than 20. Cams and a bit more airflow (no more boost required) it would make 500 rwkw easily] Edited July 26, 2006 by kastin Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2360359 Share on other sites More sharing options...
r33_racer Posted July 26, 2006 Share Posted July 26, 2006 may i ask what boost that was on? I would also like to know what rear housing was used...im thinking the 1.06 i think. Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2360694 Share on other sites More sharing options...
GTROB Posted July 27, 2006 Share Posted July 27, 2006 Heyall just about got through the hole 199 pgs of this topic and by the look's of it there is a hole lot of different combo's you can do with different yr head's and so on. I'm looking to put a 3 ltr in my 91 R32 GTR. Will it work??? And is it worth it. ??? The car is currently making about 250 rwkw. It goes alright but more power is always better. (My Stinking old Falcon ute goes Harder). I'm looking at hopefully getting up around the 550 600hp mark. Am I dreaming or not??? Where is the best place to start. (Apart from getting the engine). Any feed back would be great. Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363418 Share on other sites More sharing options...
Cubes Posted July 27, 2006 Share Posted July 27, 2006 It will work fine. You will need a 4wd sump adaptor. I think its worth it, with a set of nice rods, pistons, full crank snout and possibly if you can stretch an aftermarket harmonic balancer it will rev like buggery and reliably. A balancer 'may' not be needed for reliability at high rpm (7500rpm+ or there abouts) providing you run the full oil pump drive crank collar. I don't really know to be honest, maybe some one else who has played can enlighten us. Best place to start... Finding a good rebuilder that has had plenty to do with the rb30's in the past; the rebuild is likely to be cheaper and more reliable. Pick up the phone and start making a few phone calls. Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363571 Share on other sites More sharing options...
R31Nismoid Posted July 27, 2006 Share Posted July 27, 2006 for 550rwhp i'd be sticking with the 2.6ltr. No need to go to the addes cost/effort when the 2.6ltr already does an exceptional job with lowmounts Just my thoughts though Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363575 Share on other sites More sharing options...
Cubes Posted July 27, 2006 Share Posted July 27, 2006 It really depends what you want out of the car and its one of those things where you really need to feel how the 3ltr transforms the car. The mid range is simply awesome and mate that with 4wd, its unreal. I could never go back..... To put it in perspective. A stock rb25det making 190rwkw odd (12psi) running the usual pfc, fmic, exhaust. An rb30det running a gt35r .82 (18psi) at no point makes less power anywhere down low (2500-3500rpm) than a rb25det even though the rb25det still runs its stock small quick spooling turbo. So essentially it lunges off idle better than an rb25 then feels like an rb25 from 2500-3500rpm then it snaps and turns in to a monster. Pretty damn good for such a big turbo. Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363582 Share on other sites More sharing options...
R31Nismoid Posted July 27, 2006 Share Posted July 27, 2006 GTR boxes have a hard enough time as it is, adding massing torque doesnt help the fragile 3rd without forking $$$ out for gearsets Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363593 Share on other sites More sharing options...
GTROB Posted July 27, 2006 Share Posted July 27, 2006 (edited) for 550rwhp i'd be sticking with the 2.6ltr.No need to go to the addes cost/effort when the 2.6ltr already does an exceptional job with lowmounts Just my thoughts though I have considered sticking with the 2.6 but I'm a little bit old school and have alway worked with if you want more power/torque, you need more cube's. I also don't really want to blow the origianl block up. 3 ltr block's are a dime a dozen so you can keep busting them and it's not really a huge problem. Edited July 27, 2006 by GTROB Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363775 Share on other sites More sharing options...
Sydneykid Posted July 27, 2006 Share Posted July 27, 2006 (edited) Sydney Kid What exhaust houseing size on the gt35/40 did you use in the following setup? and have u got any dyno pics?Cheers Jon [There were very few "brand" name parts used; Standard RB30 block, crank, water pump, oil pump and balancer Balanced up & down and round & round bits O'ringed block and double annealed copper head gasket ACL Race Series pistons, rings and bearings Pistons were ceramic coated on the crowns and oil retention coated on the skirts Argo I beam rods with ARP rod bolts Std VL RB30 Commondoor gaskets and seals Fabricated sump with wings and baffles ARP studs for cylinder head and main bearings Std RB26 Camshafts, valves, retainers and followers Performance brand valve springs Adj camshaft pulleys (no name brand, early Jun style) Gates cambelt Ported head with polished and matched combustion chambers GT35R on a no name high mount manifold with a no name (HKS copy) wastegate 850 cc Cosmo injectors Bosch 044 fuel pump Nismo regulator on the standard fuel rail Power FC PWR intercooler Q45 AFM Run in on the dyno for around 1 hour all up, change oil and filter and get into it. Calcs.......... 632 bhp = 472 kw less ~60 kw (2wd) = 412 rwkw The average power from 4,000 rpm to 7,000 rpm is massive and it's not straining at all. A/F ratios are not over 12 to 1 anywhere and the knock is less than 20. Cams and a bit more airflow (no more boost required) it would make 500 rwkw easily] Ah the old RB30, used it in the car once and then someone paid me enough for it so I could build a bigger and better RB31DET. The GT35R had a 1.06 A/R turbine, with the T4 flange. The compressor A/R was 0.70. Boost was ~1.7 bar (25 psi), the dyno graphs went with the engine as part of the sale. The limiting factor with that engine were the camshafts, it really needed something bigger than the standard RB26 cams. Then I could have ported it a little better and run a slightly higher compression ratio. The RB31DET has more capacity, JE pistons, gapless rings, 272/10.3mm Jun cams, Jun camshaft pulleys, Jun valve springs, N1 oil pump with crankshaft collar, ½ mm bigger head studs and a GCG T04Z “special” turbo with a Tial wastegate. The sump on the old engine was a “recycled” bottom half, adapted to the RB30 standard sump upper half. It only had 2 one way doors, smaller wings and a rough windage tray. The RB31DET has a brand new High Energy full circuit race sump, with large wings, baffles, 4 one way doors and a proper directional screen windage tray. I am not looking for any more max power, just lower boost and more throttle response plus another 500 rpm on the useable rpm range. Best part is it’s nearly finished, we have a race meeting this weekend then next week I am into finishing it. cheers Edited July 28, 2006 by Sydneykid Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2363854 Share on other sites More sharing options...
FORZA-MOTORSPORT Posted July 28, 2006 Share Posted July 28, 2006 RB30DET CRUSE TONIGHT who is keen? so far CUBES FOOLBOOST Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2364403 Share on other sites More sharing options...
Cubes Posted July 28, 2006 Share Posted July 28, 2006 Post it in the SA section Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2364408 Share on other sites More sharing options...
FORZA-MOTORSPORT Posted July 28, 2006 Share Posted July 28, 2006 Ok you can do it your know your stuff Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2364422 Share on other sites More sharing options...
mr_rbman Posted July 28, 2006 Share Posted July 28, 2006 Post it in the SA section mmmm, could be in on this, got my pineapples to test out! Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2365223 Share on other sites More sharing options...
GTR-Ben Posted July 28, 2006 Share Posted July 28, 2006 for 550rwhp i'd be sticking with the 2.6ltr.No need to go to the addes cost/effort when the 2.6ltr already does an exceptional job with lowmounts Just my thoughts though Except when you kill the crank in your RB26 and have to fork out for the new one etc... I like the RB30 bottom end for how cheap the parts are while making good power. Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2365528 Share on other sites More sharing options...
SLIMVLT Posted July 28, 2006 Share Posted July 28, 2006 so what turbo would be beter on a rb25/30 a, gt 35r .82 or a gt 35/40 .86 (i think) im chasing 350 rwkw or so and am leaning towards the 35r but im a bit unsure. what are ppls experiances with them. i know that off boost responce will suffer abit but this is not an issue, has any1 else got either of these turbos on there cars and what results do u have, like what revs do they spool and what inlet manifold are u using with them does any1 have a g-ready plenmum with either of these tubos, and if they do did they notice any diference in spool time between the std long runner inlet manifold and the short g-redy1. thanks Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2365865 Share on other sites More sharing options...
r33_racer Posted July 28, 2006 Share Posted July 28, 2006 I do gt35 .82ar & Greddy Plenum...and i dont think the manifold makes any real world difference. However it makes changing spark plugs easier, unclutters the bay, makes fitting the rb30det so much easier, as there is no worries with height issues:) I maybe wrong but i think those two turbos are the samething arent they, just people use the two different names to describe that particular turbo. Ones a old name and the other is the new name?? Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2366425 Share on other sites More sharing options...
kastin Posted July 29, 2006 Share Posted July 29, 2006 Thats what i thought, same turbo..., what rpm are you on full boost by r33racer? or have u giot any dyno pics? Cheers Jon Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2366493 Share on other sites More sharing options...
phee Posted July 29, 2006 Share Posted July 29, 2006 I am rebuild my motor as some of you might remember and I am going to put an rb30 block on an rb25 head. Anyway, I am getting everything done and I am curious to find out what are the best parts to put in her. I am not out to buy the most expensive brand named parts simply cause of their label, I just want something that is affordable and that will work. I have tried looking on SAU but being new to the game I am a bit lost. The motor I want to be good for around 600hp at the fly. Do you know what parts I should get for this amount of power? I have a mechanic getting a quote for me but I want to be able to know what he is on about. I only know the main parts that need replacing. Pistons = Rods = Cams = Oil pump = Fuel pump = Injectors = Also ARP rod bolts, ARP main bolts, ARP head studs. Should I be getting more springs/valves etc for that amount of hp? Sorry, but I am new to this and don't even know if I am making any sense, let alone an ass of myself. Phee Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2366528 Share on other sites More sharing options...
shanef Posted July 30, 2006 Share Posted July 30, 2006 Alrighty phee your on the right track, but i hope i can help you some more. Also read the RB30 DOHC Guide, found at the bottom of Cubes's post. First the bottom end. For that sort of HP, i was told to go for argo rods. This being they can and will stand up to the HP ur looking for, and also the torque you will get form the rb30 bottom end. Next is bearings, all you need is the ACL Race Series bearings. Pistons, i cant remember what ones were the "best" but will update when i can find that out. Also yep, ARP rod bolts, ARP crank stud bolts (AKA main bolts) ARP head studs. Oil & water pump, SydneyKid said to use the gtr N1 oil & water pumps, & the JUN oil collar adapter for the oil pump. Depends on the use of the car will determine the type of cams you go for, and this will also determine if you need to go to aftermarket springs. As an example, for my car (rb26/30 in 32 gtr) i'm using it for circuit work and am using JUN 264 duration 9.25mm lift IN, JUN 272 9.25mm lift EX. Thus i dont need to upgrade the valvetrain because im not running lift over 10.5mm. Fuel pump wise i did some research and was scared by the amount of failures of one pump and then that causing the engine to lean out ending in a rebuild with the use of 2 or more inline pumps. So i went for a single SX 1000hp pump. Injectors, 750cc's be enough? or to be safe, just get some 800cc's. You'll also need to look at the machining side of things. Work i'm getting done is the exhaust port is getting re-profiled, manifolds getting match ported to the head, external oil return to the sump (from back of head from one of the welsh plugs, into the sump) and the oil galleries modified (dont ask to what extent, caus i dont know ). Now that should give you a bit more of an idea of what ur up against. Hope you have fun with it, and if you need to know more, dont hesitate to ask. cheers Shane Link to comment https://www.sau.com.au/forums/topic/15420-r33-rb30-conversion/page/183/#findComment-2367678 Share on other sites More sharing options...
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