Rambo 0 Posted September 18, 2009 What Do you guys think, Gt30 + 268 cams on a VR6. Everything standard except for a fuel pressure regulator, 2.5in straigth through exhaust and head gasket. I have heard people say its hard to map, and it will have real bad ideling. Is this true? And what sort of power would I expect. Quote Share this post Link to post Share on other sites
carpoid 0 Posted September 18, 2009 Just about all you need to know is in here mate :grin: http://www.the-corrado.net/.archive/forum/viewto ... =1&t=27844 Quote Share this post Link to post Share on other sites
Rambo 0 Posted September 24, 2009 Guys I got the turbo, its all in, just need to setup the boost controller, and the bov and get it mapped. Now I want my vr6 to breath more, let more air in and let more air out. Im guessing the best way to do that is to use Cams. But I dont want to push the power band higher or lower, i just want over all more breathing, I want the cams to open more and open for longer (i think), but i want the power increase to be all over the rev range, what would be able to do that. I have a turbo on the vr6, but want a way to load more air into the combustion chamber. Quote Share this post Link to post Share on other sites
Conker 0 Posted September 26, 2009 Guys I got the turbo, its all in, just need to setup the boost controller... F'kin hell you don't hang about!!! :salute: Quote Share this post Link to post Share on other sites
VR6 0 Posted September 26, 2009 Could be wrong but I think it was already attached to the engine as it came out of another car ... Still, good work! Quote Share this post Link to post Share on other sites
Toad 0 Posted September 26, 2009 268s have too much overlap, the standards or 263s are better. Check the FI VR6 thread as mentioned above... Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 26, 2009 Guys I got the turbo, its all in, just need to setup the boost controller, and the bov and get it mapped. Now I want my vr6 to breath more, let more air in and let more air out. Im guessing the best way to do that is to use Cams. But I dont want to push the power band higher or lower, i just want over all more breathing, I want the cams to open more and open for longer (i think), but i want the power increase to be all over the rev range, what would be able to do that. I have a turbo on the vr6, but want a way to load more air into the combustion chamber. Schimmel 263 cams, big valve head, gasket matched intake ports and leave the exhaust ports alone. Trust me, that will completely wallop a stock VR6 head and cam's flow and you WILL get gains everywhere. If you want more, then 268 cams, they WILL move the power band. I like your style. More power from flow rather than simply turning the boost up :salute: 268s have too much overlap, the standards or 263s are better. Check the FI VR6 thread as mentioned above... Not always true my friend. It's all about balancing the turbo's pressure ratio with overlap quite carefully. Obviously you don't want too much exhaust reversion bouncing back into the intake strokes, but that's inevitable, but on some turbo engines a bit of overlap can actually introduce more fresh air and fuel into the cylinders as the valves overlap, which can help push the nasty exhaust fumes out. It's very much engine dependant. The SP 263s do work very well on the VRT though, as do his 268s :salute: Quote Share this post Link to post Share on other sites
Toad 0 Posted September 26, 2009 268s have too much overlap, the standards or 263s are better. Check the FI VR6 thread as mentioned above... Not always true my friend. It's all about balancing the turbo's pressure ratio with overlap quite carefully. Obviously you don't want too much exhaust reversion bouncing back into the intake strokes, but that's inevitable, but on some turbo engines a bit of overlap can actually introduce more fresh air and fuel into the cylinders as the valves overlap, which can help push the nasty exhaust fumes out. It's very much engine dependant. The SP 263s do work very well on the VRT though, as do his 268s :salute: Sorry Kev, I was assuming that we were talking Shrick 268s, with the overlap shown below. I know that some overlap can be beneficial, especially in helping the turbo spool up, plus cooling things down a little. Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 26, 2009 Yeah when people say "268" it's easy to assume Schrick :D The Schricks are better suited to normally aspirated VR6s as you say, but I've seen a dyno plot of those used on a VRT though and it looked surprisingly good tbh! Can't remember where it is now, think it's on the Vortex. I bet the idle and midrange weren't all great though. Everyone thinks loads of overlap means boost flying straight out of the exhaust, but you need a VERY severe cam to achieve that :D Only way to do cams properly on a turbo engine is to measure intake and exhaust back pressures. If exhaust back pressure is less than intake pressure, the cams are unsuitable. Quote Share this post Link to post Share on other sites
Rambo 0 Posted September 27, 2009 So, the general consenses is that 268's will increase power and torque over the whole rpm range. Theres a lot of talk about 268's, but I have heard you can get specific turbo cams, Sp Turbo 263 cams. Does any one know about them. There a little more expensive than the 268's. Anyway if any one wants to see the build of the turbo here it is. /viewtopic.php?f=11&t=84486 Quote Share this post Link to post Share on other sites
Rambo 0 Posted September 27, 2009 I got a question about my wastegate. I think I damaged it some how. Its an external wastegate, with a 10psi spring in it. But the wastegate is always open, even at idle, half the fumes are going out the exhaust manifold and half are exiting the wastegate. So the turbo does not kick in. I have not set up the boost controller yet, but surely the 10psi spring should keep the wastegate closed until the pressure gets close to 10psi. Quote Share this post Link to post Share on other sites
