Eightdip Posted December 30, 2020 Author Share Posted December 30, 2020 7 hours ago, Noz said: Very cool. Hope I get to see this in person when it's done. Why not create elbow outlets? So they point upwards, if their direction is an issue. It'll definitely be getting used and abused so you'll hopefully see it out and about! Do you mean elbow trumpets? If so there wasn't even any room to start the elbow on the back cylinder on the old kit unfortunately 1 Link to comment Share on other sites More sharing options...
Herb Posted December 30, 2020 Share Posted December 30, 2020 I think with trumpets that short you might gain power up top and loose some down low. But it depends on so many things with NA builds that it‘s hard to say. I guess it remains to be seen how it all comes together in the end. 1 Link to comment Share on other sites More sharing options...
Noz Posted December 30, 2020 Share Posted December 30, 2020 I mean turn the black trumpet into a 90 degree elbow. There's room there but it'd have to be designed. Link to comment Share on other sites More sharing options...
Eightdip Posted December 30, 2020 Author Share Posted December 30, 2020 6 hours ago, Noz said: I mean turn the black trumpet into a 90 degree elbow. There's room there but it'd have to be designed. There's only room now as the actual bodies are shorter, there wouldn't have been room on the previous kit, the throttle body was pretty much up against the body of the car Link to comment Share on other sites More sharing options...
Eightdip Posted December 30, 2020 Author Share Posted December 30, 2020 9 hours ago, Herb said: I think with trumpets that short you might gain power up top and loose some down low. But it depends on so many things with NA builds that it‘s hard to say. I guess it remains to be seen how it all comes together in the end. That would be my guess as well, but we shall see! Would prefer power up top than down low to be fair Link to comment Share on other sites More sharing options...
Noz Posted December 31, 2020 Share Posted December 31, 2020 But I can see the black trumpet there mate? If you had a tiny trumpet it would fit. Removing that black trumpet and replacing with one that had the same diameter just an elbow would fit. You would just need to remove the black trumpet. It would need to be a cnc job, and be in a few pieces of course. Link to comment Share on other sites More sharing options...
Eightdip Posted December 31, 2020 Author Share Posted December 31, 2020 1 hour ago, Noz said: But I can see the black trumpet there mate? If you had a tiny trumpet it would fit. Removing that black trumpet and replacing with one that had the same diameter just an elbow would fit. You would just need to remove the black trumpet. It would need to be a cnc job, and be in a few pieces of course. This is how it was before and why I had to change the kit, not a feasible space for a trumpet even if it was pointing up Either way, I'm much happier with the space we're dealing with now with the shorter bodies 2 Link to comment Share on other sites More sharing options...
L337 Posted December 31, 2020 Share Posted December 31, 2020 On 12/20/2020 at 9:19 PM, Eightdip said: Not 100% sure to be honest! Why do you ask? *Updated* There's an optimum length depending on what rpm you want peak power to be achieved at. From memory though, 45mm ITBs would be the ideal diameter for <250/260bhp, 48mm would be required if chasing 300bhp+ *for 86mm bore* *I think as a rough estimate calc: for peak power at 6000rpm, the length from back of the intake valve to the bellmouth of the trumpet should be 345mm. Formula I used is (angular displacement × intake air speed) ÷ (time in seconds intake valve closed for × target peak rpm) Where: - Angular displacement I think was something to do with timing, but could be assumed to be 85degrees for rough calcs. - Intake air speed also assumed to be 330m/s - 2JZGE non-VVTI has 233deg intake cam, so at 6000rpm intake valve is closed for 0.0135 seconds * Huge caveat, doing a lot of this from memory of uni days... May have gotten all/some of it wrong! Although the answer sounds about right IMO. 1 Link to comment Share on other sites More sharing options...
Eightdip Posted January 1, 2021 Author Share Posted January 1, 2021 On 12/31/2020 at 3:00 PM, L337 said: *Updated* There's an optimum length depending on what rpm you want peak power to be achieved at. From memory though, 45mm ITBs would be the ideal diameter for <250/260bhp, 48mm would be required if chasing 300bhp+ *for 86mm bore* *I think as a rough estimate calc: for peak power at 6000rpm, the length from back of the intake valve to the bellmouth of the trumpet should be 345mm. Formula I used is (angular displacement × intake air speed) ÷ (time in seconds intake valve closed for × target peak rpm) Where: - Angular displacement I think was something to do with timing, but could be assumed to be 85degrees for rough calcs. - Intake air speed also assumed to be 330m/s - 2JZGE non-VVTI has 233deg intake cam, so at 6000rpm intake valve is closed for 0.0135 seconds * Huge caveat, doing a lot of this from memory of uni days... May have gotten all/some of it wrong! Although the answer sounds about right IMO. That's some serious info haha, literally had no idea about any of that. Thanks for sharing bud! The cams I'm using are BC 272 deg (intake and exhaust I believe), plus I have vernier pulleys so I guess that would change the calculations. Think there's going to be a fair amount of playing around when mapping Link to comment Share on other sites More sharing options...
L337 Posted January 1, 2021 Share Posted January 1, 2021 14 minutes ago, Eightdip said: That's some serious info haha, literally had no idea about any of that. Thanks for sharing bud! The cams I'm using are BC 272 deg (intake and exhaust I believe), plus I have vernier pulleys so I guess that would change the calculations. Think there's going to be a fair amount of playing around when mapping 272s will be interesting! What are/will you be revving it out to? Link to comment Share on other sites More sharing options...
Eightdip Posted January 2, 2021 Author Share Posted January 2, 2021 6 hours ago, L337 said: 272s will be interesting! What are/will you be revving it out to? I'm only running steel BC springs/retainers rather than Ti so it won't be as high revving as it could be but hopefully we'll be able to squeeze a bit more out of it. All depends on the power curve to be honest, if power's still going up to the rev limit then we'll look to increase it! Link to comment Share on other sites More sharing options...
Herb Posted January 2, 2021 Share Posted January 2, 2021 I‘m running the BC 264‘s in combination with the BC Valve Springs and Ti retainers. Nice bit of kit! Probably the best mod on the NA head in my opinion. Link to comment Share on other sites More sharing options...
Eightdip Posted January 3, 2021 Author Share Posted January 3, 2021 9 hours ago, Herb said: I‘m running the BC 264‘s in combination with the BC Valve Springs and Ti retainers. Nice bit of kit! Probably the best mod on the NA head in my opinion. Out of interest did you notice much difference from standard with the 264s Herb? Link to comment Share on other sites More sharing options...
Herb Posted January 3, 2021 Share Posted January 3, 2021 (edited) 8 hours ago, Eightdip said: Out of interest did you notice much difference from standard with the 264s Herb? Yes definitely! It transformed the car. Much more rev happy and lively and quite a few ponies too on the dyno (of course with a full remap on my AEM V2). The great thing with the 264s is that the car still maintains good manners for street driving. The idle is rough when compared to standard cams but not too rough. Not race car stuff but more like a 997 GT3 RS or similar. Can definitely recommend! I guess it will be similar with the 272s. Edited January 3, 2021 by Herb (see edit history) Link to comment Share on other sites More sharing options...
Herb Posted January 3, 2021 Share Posted January 3, 2021 I would also recommend to do the valve stem seals while you’re at it. You‘re basically already there when you do the valve springs/retainers. Also consider to use BC billet valve locks for your BC springs/retainers combo. 1 Link to comment Share on other sites More sharing options...
Noz Posted January 3, 2021 Share Posted January 3, 2021 What did it dyno with the 264s added? Link to comment Share on other sites More sharing options...
Eightdip Posted January 4, 2021 Author Share Posted January 4, 2021 Also keen to know what it dyno'd! Yeah valve seals were done when they did the springs retainers and shims 1 Link to comment Share on other sites More sharing options...
Herb Posted January 5, 2021 Share Posted January 5, 2021 Well I have to say that I‘m not the kind of guy that drops dyno sheets in forums etc. haha. It is not a clear statement that I can give regarding the cams themselves because the engine reveived some other mods as well at the time (mainly ignition and EFI related). However, to say the least the car is much more lively above 4-4,5K rpm showing a gain of about 25hp (crank hp) compared to the setup that I ran before. And that is quite significant for NA terms in my opinion. Regards, Herb 1 Link to comment Share on other sites More sharing options...
Eightdip Posted February 18, 2021 Author Share Posted February 18, 2021 Ok a long overdue update! So I decided to go for Whifbitz coilpacks instead of the standard dizzy and HT leads, apparently it'll be easier for mapping plus I reckon looks a lot cleaner. Throttle cable is hooked up to the pedal and just needs a bracket fabricating so it's not just flopping on top of the rocker covers. New (iridium) plugs have been put in (old ones were looking a little worse for wear!). A bunch of minor annoyances sorted and the wiring/loom work is getting there. Wideband is also ordered 2 Link to comment Share on other sites More sharing options...
Herb Posted February 18, 2021 Share Posted February 18, 2021 Thanks for the update! You will not regret your decision regarding the Whifbitz COP conversion. Absolutely love mine. Much more modern system and also cleaner in terms of looks. Link to comment Share on other sites More sharing options...
Herb Posted February 18, 2021 Share Posted February 18, 2021 3 Link to comment Share on other sites More sharing options...
Noz Posted February 18, 2021 Share Posted February 18, 2021 Looking good man be nice to hear this. 1 Link to comment Share on other sites More sharing options...
Eightdip Posted February 19, 2021 Author Share Posted February 19, 2021 On 2/18/2021 at 7:44 PM, Herb said: Yeah def looks much cleaner! Paint on the covers looks sweet my dude Link to comment Share on other sites More sharing options...
Herb Posted February 20, 2021 Share Posted February 20, 2021 8 hours ago, Eightdip said: Yeah def looks much cleaner! Paint on the covers looks sweet my dude Thank you! 1 Link to comment Share on other sites More sharing options...
Suprajza80 Posted February 22, 2021 Share Posted February 22, 2021 This is wicked love the way its all getting on ..good job mate 1 Link to comment Share on other sites More sharing options...
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