eatthis 0 Posted September 14, 2006 how reliable are they? and what kinda power gains do you get? Quote Share this post Link to post Share on other sites
PhatVR6 0 Posted September 16, 2006 84mm pistons I believe, I don't think it'll bore much further than that don't see why it'd be any less reliable if it was put together right in the first place. Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 16, 2006 Because the bores are perilously thin beyond 83mm. You only have to fondle a bare block to feel that....there's not much metal there at all. Odd though that the stock internals can take 450hp before forged pistons and rods are called upon! Apparently a 100mm throw crank (which exists according to a reliable source) and with 85mm of bore, makes 3.4 litres. I personally think 85mm bore is pushing your luck way too far.....but I've been told it'll work! Quote Share this post Link to post Share on other sites
Chris VR6nos 0 Posted September 17, 2006 I'm curious to find out if we can get the VR block relinered, then we are looking a a VR40 easily then you are able to atain 1000bhp for sure. Chris Quote Share this post Link to post Share on other sites
vdubjb 0 Posted September 17, 2006 The gains from boring arent worth the cost, unless the bores are out of whack and you are need of a rebuild. Quote Share this post Link to post Share on other sites
Chris VR6nos 0 Posted September 17, 2006 The difference here are to do with forced induction, if you are running 7 or 8psi you are making the engine effectivelly 50% larger than the same size engine in N/A form so you can see when it comes to FI the reboring is very effective in power production as a step. So boring out 200cc larger will transpose into 300cc larger with a mere 7 psi and some lads here are running 12+psi so work it out for yourself from there. Chris Quote Share this post Link to post Share on other sites
vdubjb 0 Posted September 17, 2006 If you want to make moe power in F/I, just turn up the boost. It's easier, and safer to buildup a stock bored car. The real key to vr6 power is in the head. Get air in and out of the head efficiently. Port matching and a log intake will more than match any increase you get from larger bore. Going into the bottom end of a vr isnt cheap. Plenty big power cars running stock bottom ends. Vic from Eurosport had a 3.2 litre corrado. I believe that may have been the largest non stroked vr I have encountered. If you get the block sonic tested, you ca really determine how far you can go. I ust think it's a huge waste of money unless you are doing the work yourself, cheaply, or for contingency money. Quote Share this post Link to post Share on other sites
PhatVR6 0 Posted September 17, 2006 The real key to vr6 power is in the head. Get air in and out of the head efficiently. Port matching and a log intake will more than match any increase you get from larger bore. . exactly, so why bother throwing money at a 12v when the cosworth designed 24v R32 head is bound to flow a hell of a lot better. especially if yuo are going turbo and talking about going for aftermarket management, it makes no sense whatsoever to stay with a 12v. And I'm not being elitist, I'm talking plain and simple facts. Quote Share this post Link to post Share on other sites
eatthis 0 Posted September 17, 2006 r32 and cosworth in the same sentence im salivating uncontrollably now Quote Share this post Link to post Share on other sites
Chris VR6nos 0 Posted September 17, 2006 The thing is, the 24v head to my knowledge won't fit the VR and i can't go to the expense and difficulty of the R32 so boring is a cheap option with the rebore at around £200 or less and pistons at £50 each plus duty etc so other than gaskets all the work is done by me and remapping is the same cost whatever size the lump is so that's trhe thinking behind it. I'm not going to do this at the moment mind but thoughts are always in my head and sometimes things come of them. 24v will always be the aim though for flow regardless. Chris Quote Share this post Link to post Share on other sites
eatthis 0 Posted September 18, 2006 i can confirm that the 2.8 24v head will not fit the 12v bottom end Quote Share this post Link to post Share on other sites
CoxyLaad 0 Posted September 18, 2006 yes that is true. The spark plug are in the head on the 24v anyway, so you may encounter a slight compression problem! The price of 24v motors is coming down. There is no point in investing a large amount of money on a 12v (unless you already have a lot of money invested in it) I think people are put off by the wiring. Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 18, 2006 A 24V makes a nice upgrade over a 12V if installed as it is. Decent ECU, variable geometry and timing etc. For forced induction 12Vs, the upgrade to a 24V makes a less convincing argument. As brooklyn says, just turn up the boost! If 680whp+ wouldn't be enough for you as a 12V turbo owner, then you have issues, but ulimately the larger capacity of the 24V (R32) and a freer flowing head will net you that bit extra top end for the 800-1000hp league....but even then turbo size is still the governing factor. Quote Share this post Link to post Share on other sites
PhatVR6 0 Posted September 18, 2006 it's like turboing an 8v, instead of a 16v or a 20v. Pointless. sure, you can get 700bhp with the 12v, but it'll cost you more. the same parts fitted to a 24v will net you more horsepower, fact. Quote Share this post Link to post Share on other sites
Toad 0 Posted September 18, 2006 it's like turboing an 8v, instead of a 16v or a 20v. Pointless. sure, you can get 700bhp with the 12v, but it'll cost you more. the same parts fitted to a 24v will net you more horsepower, fact. Sometimes some people prefer the old stuff..... It's being an individual, mate, I understand that the 24v will get you more power etc etc, I think everyone understands that. But perhaps some people want to stay 'old school'. Not everyone might consider it 'pointless'. How come every thread about increasing the capacity of the VR or trying to get more power out of it ends up in a 12v vs 24v argument? I thought the question was about 3.0 VRs and power gains/reliability after all. Quote Share this post Link to post Share on other sites
Stan 24v 0 Posted September 18, 2006 24v is the way forward!!! Only kidding, just wanted to add to the post above by Toad :lol: Off topic, slightly: Where can you get a turbo for a 24v anyway? Quote Share this post Link to post Share on other sites
vdubjb 0 Posted September 19, 2006 24v is the way forward!!! Only kidding, just wanted to add to the post above by Toad :lol: Off topic, slightly: Where can you get a turbo for a 24v anyway? http://www.eiptuning.com/eip/index.html Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 19, 2006 it's like turboing an 8v, instead of a 16v or a 20v. Pointless. sure, you can get 700bhp with the 12v, but it'll cost you more. the same parts fitted to a 24v will net you more horsepower, fact. Assume you mean the SA crossflow 8V? You think 100hp here or there at that level is going to make a massive night/day difference? Quote Share this post Link to post Share on other sites
Toad 0 Posted September 19, 2006 24v is the way forward!!! Only kidding, just wanted to add to the post above by Toad :lol: :D Quote Share this post Link to post Share on other sites
Stan 24v 0 Posted September 19, 2006 24v is the way forward!!! Only kidding, just wanted to add to the post above by Toad :lol: Off topic, slightly: Where can you get a turbo for a 24v anyway? http://www.eiptuning.com/eip/index.html :shock: 8) :twisted: Quote Share this post Link to post Share on other sites
Toad 0 Posted September 19, 2006 Bloody hell!!! I just looked at the prices!!!! $7000 for Stage 1 4-450hp? $35 per additional horse power? Sorry, going O/T. Quote Share this post Link to post Share on other sites
Chris VR6nos 0 Posted September 19, 2006 I like the charger and will play with it for some time yet, i have a turbo'd car i can use everyday but it usually just sits there, and it has nitrous on it so it's all down to what you wantm the Skyline is at 650bhp and would put it against any Corrado on the forum but i choose to use the VR simply because i like it, turbo's loose thier lustre just as easy Kev and you have different problems with them, you'll be fed up of the turbo setup more times than enough i'll promise you and this forum will document your experiences as i'm sure you'll blog it all down, it seems like the grass is greener on the other side but when you get there it tastes pretty similar. Power isn't everything to me and which ever route people take i hope to read good results and interesting comments, after all this is what the forum is all about. Chris Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 19, 2006 Well that remains to be seen, but thank you for your pearls of wisdom any way :-) Tried the charger, liked it, now I'm ready for something else! If that doesn't float my boat, then I'll keep going until I find something that does tickle my fancy ;-) Quote Share this post Link to post Share on other sites
Chris VR6nos 0 Posted September 19, 2006 I have a feather! I seem to have less and less to say as time goes on, maybe it's time for a new car. Chris Quote Share this post Link to post Share on other sites