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pf.

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Posts posted by pf.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted

    oh cool, yah u don't wana make to much power with this NA build..

    If I was aiming at say 10k I would be better off using the 25 or 26 head as the air speed of the ports would favour dual valve intakes. This would also increase costs immensely as I would not only need to spend more on the head but also more on the rotating assembly as I would *want* a fully counterweighted crank. Revving the engine into 10k and past territory would also mean I would need to spend alot more on the gearbox for a small percentage gain over a much cheaper 8k rpm build.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted

    Ok I have been going slow with the build I got the head back before machining to bolt it up the block is in my backyard atm I just setup my engine stand at work so I will be taking photos soon.

    I will make a new thread soon and leave this one here for tech discussion.

    I will say a engine needs air fuel and spark it gives no farks for how many valves are delivering the air/fuel to it. My head can be flowed for 350hp with 1mm oversized valves so I roughly know that it will need to spin at 8k maybe a little more to make that. My cam choice will be made for about 8k with a 2.6l (due to bore size) engine at 8k I think I will need to limit power to about 320 330 to stay just under 8k rpm.

    There is also the points that I made earlier in the thread about the 2v head being vastly cheaper and easier for me to work with. If you have not make sure you read the quotes on the first two pages as these points made by a pro engine builder are quite true.

    The build thread will start when I get time to move my engine the head is bare so ill just be mocking up for a while. I also don't have much cash so progress will not be overnight :)

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    I am a mechanic guys I have been involved with and have driven very fast cars I want a turbo yes but I don't froth over turbos like some.

    I don't mind having less power if I can use the power I have IE: racetrack style torque profiles.

    I have seen rb30 heads that flow enough for 330hp which would want my engine to spin at about the mark I am looking for 8k which is where I will be shooting.

    My engine stand comes soon dedicated to this build pistons are next $700 ill be contacting crankshaft rebuilders for a price to do the crank and I am thinking 26 rods.

    The head is back to me before machining so I can work out belt's and other little things a mate just blew to 30's at the mattsuri comp so ill be having one for bolts and other parts.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    I don't care if this does not make 11ty billion killer wasps I still don't understand what the fuss is over peak power figures ffs. I have no care for dick size contests the engine I will build will be plenty fast for my needs.

    Also this is the n/a section of the forum not the turbo section so why are you intent on annoying me with turbo this and turbo that.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted

    Far out bro, i think this whole build is rediculous and throwing away money u won't get back, hope u realise a 2JZ is good for 600hp stock internals!! The worlds fastest NA-Turbo supra runs 7.77, thats right with NA Bottom end!! Even a 1JZ VVT will make rediculous power and has higher potential over 33 rb25 and will last longer. U can buy these motors with everything u need for way less.

    But if u want most bang 4 ya buck, i'd go rb25 neo - More torque over r33, stronger internals, VVT, newer/lesskm's. Just thrown on a head gasket and youre good to go for some serious HP depending on supporting mods. Like others said it's in you're best interests, both HP and financially to cut youre losses and stop b4 it gets way out of hand!

    I dont mind a 30/30 as the single cam can be ported and get good power, but next you'll be saying to scap the E and go with C (Carby) to get more power.

    You've turned a RB25DET into a RB25DEBT, cuz b4 it even turns over youll have no money left.

    I am not building a turbo engine. As for bottom ends you have no idea I will be using different pistons as the 25 pistons will drop the compression the head is bent so after machining I hope to see near 12:1.

    Con rods will be changed other than that the rest is identical thinking AM forge I beams or peen'd and machined 26 rods"..

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted

    Ok a bit of an update head was checked by me and was bent it can be straightened. The straightening will increase compression greatly but he 25 block will drop it greatly so I have some numbers to play with :) So far the head is going to cost me about 2500 I plan on spending 2k on the computer and ignition so to come under the 10k mark it leaves me with 5k for block and fuel system. Costs will blow out so I have to play it safe with my money.

    The head price is service,porting,machining and a cam.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    So your saying (160 rwkw) "ONLY" which equates to 208kw at the engine, which is what everyone uses...car dealerships etc... a brand new showroom falcon xr6 has what 210kw???? except its 2013 technologoy, not half 86 half 96.....over 20 year old parts..... "ONLY"

    Ok it is a good amount but it is not in any way remarkable look at the hp per cc it is fairly average considering you can buy a r1 tune it and make near 200hp.

    Also the e36 BMW's can make 300hp with a few mods the xr6 falcon is pretty much the same engine from the xf's just with 4 valves per cylinder. What is the hp per cc or ci of a xr6 compared to some older cars there are some that do near the same.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    ask gerg_r31 or have a look at his R31 N/A thread. That was with an RB26 head though.

    There was an interesting discussion on Performance Forums about 2 valve vs 4 valve incidentally, though I believe it might have been more a comparison of V8 head design.

    Really I might have to go and check that out it sounds interesting.

    Is that the 26/30 that made only 160kw.

    If you wonder why I say only what I mean is that those figures sound very low for the perceived power it should make on paper. I myself thought how can a 26 head on a 3l block only make that much power when some 202's come close or better they aren't even crossflow.

    Refer back to the stats I quoted in a post of the m20 160kw should be doable with a 30 head so why spend the extra on a 26 head if I am not going to spin the engine past 8k?

    Falsely Accused Of Excessive Noise?

    in Victoria

    Posted

    Fight it the more people that stand up the better.

    The govco wants sheple to take shit like this lots of govco departments just say pay up it's easier...... wait hold on how stupid is this country getting.

    Like I said the more people that fight this sdhit the better thanks for you're contribution to our great country.

    Squeaking Brembo's

    in Suspension, braking and tyres

    Posted · Edited by pf.

    Have you tried using emery paper on the rotors yet? You will need something to spin them on though you could improvise using the back axle.

    Also do you know how many shims it had from factory I can't remember off the top of my head if they run one or two per pad.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    *grabs chair and waits*

    Make sure to post build photos

    Yea i'll have to start soon as it seems you guys have started to get a interest in this. First thing will be a acid bath I guess then i'll see what is next.

    Oh yea a bore on the 25 block is farked so i'll have to find some oversized N/A pistons as it is a turbo block. I will have to weigh up the cost of new rods over resizing mine vs the performance gain.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    My RB30E made 109rwkW on a dyno, it's standard with GTS1 cam and GTS2 extractors.

    Dropping $10k into it would easily make 250rwkW :P

    Do it hero, and post results (so we can laugh at you). By the time you're done, you could have bought an RB25DET.

    You came here for advice, you got it, you don't like it so you're going to fight us? Kids these days...

    I never tried to start a fight I asked for advice I have received some but I have also received comments from a smart a#$ that tried to question my reasons. I asked for the thread not to go down this path I just want advice like some I received from XKLABA thanks :).

    Like I have already stated I am building a turbo engine the engine I want advice on is a N/A engine.

    BTW what may cost you 10k does not mean I will pay 10k for the same it's called trade prices and accounts at parts shops also it makes it easy when you have a work shop.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted

    easiest way would be fit head then cut an old belt and run it around then measure it/count the teeth, then search for a belt

    PS if it isn't a Nissan replacement belt then make sure the teeth profile is right, when I searched for a belt for my 26/30 I found that one of the belts commonly use for this combo is not the correct profile

    Thanks heaps I normally only use the right part for the right car, but have done a few matchup jobs in my time.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted

    It would seem easy enough, if the block is VCT then block off the VCT oil feed and put 1-1.2mm restrictors in the other 2, use RB30 head bolts/studs for correct length for head, the hardest bit I can think of would be the correct length of the timing belt as no one I could think of would have done this before so you will have the figure that out for yourself after the head is fitted

    the RB30 head has a smaller combustion chamber the the 25/26 heads ( not sure about the NEO head, I believe it has a smaller chamber then the normal 25 head ) so the comp ratio will be higher, so checking the valve clearance would be a good idea

    that said I stand by my previous post as it's not a great idea, they went to twin cam for a reason/reasons, but I love a slapper engine and am interested to see how this turns out, GL :thumbsup:

    Yea I have not put much thought into this as of yet (the finer details) I hear you about blocking off the vct feeds. With the belt this is one thing I was thinking of today I am guessing I just have to reverse the figures from a rb25/30 so the extra length required will be subtracted instead. But I think I may be able to use a rb20e belt if gates make one.

    Rb30 Head On 25 Block

    in Naturally Aspirated Performance

    Posted · Edited by pf.

    its probably uni holidays.

    Someone claims they know what they're talking about in building engines... Still wants advice off "backyarders" on how to build engine... Lol

    Did you read my first post, obviously not I asked for any advice so I can fast track this project otherwise it will be a matter of trial and error. But so far all you have done is argue against the idea because you believe it is a bad idea. Nearly every other person has said do it and post back results which I will have to do, but you sir have kept this attitude up that you have a superior knowledge over myself. I asked politely at the start of the thread if no one could delve into the topic of why but you sir did so I replied in a just way against your unfounded theories that you tried ever so hard to thrust upon me.

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