Captain Bondo Posted January 24, 2010 Report Share Posted January 24, 2010 Austen i am surprised your flow numbers are that low actually- a stock Volvo 16v flows about 230cfm and a stock 'Yota 2jZ head flows about 250cfm (valves are about 2mm larger than stock Volvo RN valves). Have you talked to RSI at all about head development? I seem to recall they were getting north of 300cfm from late rn castings when thye were playing with them (I want to say 310 @ 28"). I don't know what sort of port volumes/velocities they were ending up with though. Link to comment Share on other sites More sharing options...
PROjectBEWST Posted January 24, 2010 Report Share Posted January 24, 2010 Austen i am surprised your flow numbers are that low actually- a stock Volvo 16v flows about 230cfm and a stock 'Yota 2jZ head flows about 250cfm (valves are about 2mm larger than stock Volvo RN valves). Have you talked to RSI at all about head development? I seem to recall they were getting north of 300cfm from late rn castings when thye were playing with them (I want to say 310 @ 28"). I don't know what sort of port volumes/velocities they were ending up with though. Do tell more! God...talking about heads makes me so horny. Link to comment Share on other sites More sharing options...
austenw Posted January 24, 2010 Report Share Posted January 24, 2010 I think the figures for my head are very good as the coefficient is 0.62 for the valve size which as good as your going to get unless you spend another 100 hours to get that extra 0.02 I suppose it all depends on what flow bench you run, what pressure, what bore size etc Yes I've been speaking alot with the guys who did all the development at TWR for the British touring cars Mine was run with 25" on an 81mm bore at 0.5 inch lift Link to comment Share on other sites More sharing options...
austenw Posted January 24, 2010 Report Share Posted January 24, 2010 Comparing my results to these taken from other peoples tests on standard valves mine is a huge inprovement Link to comment Share on other sites More sharing options...
BlackT5 Posted January 24, 2010 Report Share Posted January 24, 2010 Yes I'm running my engine N/A I'm amazed by the flow figures of the head above My head is exactly the same running larger valves with a flow coefficient of 0.62 which is about at its max for an OEM casting The British touring car head was 0.67 efficiency with a £15'000 custom head, that ran 325bhp at 8500rpm I'm amazed you managed 290cfm with smaller valves than me, 50cfm is a huge difference for the same head at similar pressures Can you post up flow results That is not my motor, it is one built by a guy in Sweden. I have asked for the flow sheet. I found out the cams have a lift of 11.8mm and 290 degrees Link to comment Share on other sites More sharing options...
austenw Posted January 24, 2010 Report Share Posted January 24, 2010 This is picture I found a while back from a thread Is this your head? The error they have made when flow testing this head is to use a 3.4 inch bore which is 86.36mm I dont know of any Volvo 5 cyl running that size bore Either 81mm or 83mm else it will show inflated figures as the valves are deshrouded which is not a real world tests in my opinion Link to comment Share on other sites More sharing options...
BlackT5 Posted January 24, 2010 Report Share Posted January 24, 2010 Not my head either, mine was never flowed. I think that's Chuck's head (admin) http://graphite.volvospeed.com/gallery/p17_sectionid/2 Link to comment Share on other sites More sharing options...
lookforjoe Posted January 24, 2010 Author Report Share Posted January 24, 2010 Exactly Looks like maybe there was only VVT on the intake side? /engine porn NA head? That would explain the intake side modded VVT gear... or just NA cams? Very purdy. Why the extra manual tensioner on the top? Link to comment Share on other sites More sharing options...
Chilled man Posted January 25, 2010 Report Share Posted January 25, 2010 Looks like a different crank ... Link to comment Share on other sites More sharing options...
Johann Posted January 25, 2010 Report Share Posted January 25, 2010 Very purdy. Why the extra manual tensioner on the top? I believe he is doing 9K 9200 RPM on that engine. Could be that the belt starts to wobble. Polestar is using the same setup on their 8750 RPM NA engine. Link to comment Share on other sites More sharing options...
AthruC Posted January 25, 2010 Report Share Posted January 25, 2010 Yes I'm running my engine N/A I'm amazed by the flow figures of the head above My head is exactly the same running larger valves with a flow coefficient of 0.62 which is about at its max for an OEM casting Riddle me this - who makes valves/where can you get larger valves for the late (P2) turbo heads? Link to comment Share on other sites More sharing options...
lookforjoe Posted January 25, 2010 Author Report Share Posted January 25, 2010 I believe he is doing 9K 9200 RPM on that engine. Could be that the belt starts to wobble. Polestar is using the same setup on their 8750 RPM NA engine. I see. Must be an NA head - he's got the block-off plate on the intake side, also. Guess it doesn't matter, if you're swapping out all the valves anyway... Link to comment Share on other sites More sharing options...
austenw Posted January 25, 2010 Report Share Posted January 25, 2010 Riddle me this - who makes valves/where can you get larger valves for the late (P2) turbo heads? Vauxhall 2.0 XE race valves from Paul Ivey at Race Engineered Components in the UK (REC Valves) Link to comment Share on other sites More sharing options...
kildea Posted August 26, 2010 Report Share Posted August 26, 2010 ... a stock 'Yota 2jZ head flows about 250cfm (valves are about 2mm larger than stock Volvo RN valves). the only 2jz numbers i have ever seen are more like ~220cfm @ .5" lift and 28" of water. so honestly, 240 @ the same lift and 25" sounds not-too-shabby imo. Link to comment Share on other sites More sharing options...
Captain Bondo Posted August 26, 2010 Report Share Posted August 26, 2010 They're around 230-238 at 0.5" depending on the setup. I had written down 254cfm but that was peak flow. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.