JustinOlson Posted July 17, 2007 Author Share Posted July 17, 2007 I agree that ideally you would have more of a radius then this, but this is a affordable option for those that are on a budget. Justin Link to comment Share on other sites More sharing options...
kj280z Posted July 18, 2007 Share Posted July 18, 2007 Regarding the radius on the velocity stacks... agreed Ideally increasing the radius woudl be optimal... BUT wouldn't it be possible to have the radius increased by the end user? If so, if someone wanted more, they could have it done on their own... For most applications the .25 radius would work fine IMO Link to comment Share on other sites More sharing options...
nismopu Posted July 18, 2007 Share Posted July 18, 2007 they say 7/16 to .5 is the most ideal radius for helping draw in the air but i dont know if thats true in all apps, just what i have read in a few efi books. peace. Link to comment Share on other sites More sharing options...
Tony D Posted July 18, 2007 Share Posted July 18, 2007 Not picking on you but... if the OE manifolds had 38mm runners, this thread wouldn't exist. An N42's runners are under 32mm! The runnners shown in the above manifold are 1.5", or 38.1mm. While I'm happy with the results, and its still way early in the game, I have no reason to go larger on a street duty motor. If you read the FIA Homogolation Papers for the L28E Intake Manifold, they are stating a 'blueprint' size of 35mm on each runner. I know what they actually measure, but it's interesting to see it in print. As for 'how much' you loose running a stock manifold, without giving too much of the work away---as you know JeffP is running the stock L28ET Manifold on his engine. When BC Gerolomy Ported his last head, it was done with a Cannon Manifold on it which was matched to his head, and then the stocker was match-ported as best it could be to the head. There is a definate step where the stock manifold meets his head (manifold is obviously smaller) it may be something like 1mm all the way 'round if memory serves. Anyway, when flowbenched, the runner of the stock manifold was costing Jeff 30CFM over the Triple Manifold at 28" on BC Gerolamy's Flowbench. So for those inquiring minds, there is a bit of anecdotal evidence from Jeff's melticulously researched and step-by-step development of his engine. Yes, he knows he's giving up horsepower. Yes, he knows the stock manifold has a small plenum. Yes, Yes, Yes. to all that... But his current power peak is still around 7300rpms.... Link to comment Share on other sites More sharing options...
Administrators RTz Posted July 19, 2007 Administrators Share Posted July 19, 2007 There is a definate step where the stock manifold meets his head (manifold is obviously smaller) it may be something like 1mm all the way 'round if memory serves. Tony, Do you feel there are any positive anti-reversion effects in that scenario? Link to comment Share on other sites More sharing options...
Tony D Posted July 19, 2007 Share Posted July 19, 2007 "Do you feel there are any positive anti-reversion effects in that scenario?" That is the excuse we are using to justify the loss of the 30cfm! LOL Nathan at BCG said the same thing---it will definately help with reversion during overlap. Jeff's earlier cam positively had some reversion, and didn't have nearly as big a step, but the Cannon Manifold only has maybe a .5mm step, and flows quite a bit more...well at least 30 cfm more. Maybe that step is closer to 2mm radially. I think those runners were close to the FIA Homogolation blueprint. You can't make em much bigger than that without compromising the wall thickness. Link to comment Share on other sites More sharing options...
spacecase70 Posted August 2, 2007 Share Posted August 2, 2007 any updates on the Manifold? Link to comment Share on other sites More sharing options...
240Z_478 Posted August 12, 2007 Share Posted August 12, 2007 Any Info on the prototype manifold yet?? Link to comment Share on other sites More sharing options...
JustinOlson Posted August 12, 2007 Author Share Posted August 12, 2007 I'm trying to get the machinist to get his butt in gear. I've worked with him in the past, but he seems to be very booked up right now. I've put a deposit of $650 down with him so Its hard to just split and use a different guy. I apologize for the wait. Regards, Justin Link to comment Share on other sites More sharing options...
1 fast z Posted August 13, 2007 Share Posted August 13, 2007 I'm trying to get the machinist to get his butt in gear. I've worked with him in the past, but he seems to be very booked up right now. I've put a deposit of $650 down with him so Its hard to just split and use a different guy. I apologize for the wait. Regards, Justin That why you should just invest in your own equipment, and do the work yourself! Link to comment Share on other sites More sharing options...
JustinOlson Posted August 13, 2007 Author Share Posted August 13, 2007 In a cnc or just and end mill? CNC's are out of my budget as this is just a hobby. Justin Link to comment Share on other sites More sharing options...
WizardBlack Posted August 28, 2007 Share Posted August 28, 2007 Updates? Link to comment Share on other sites More sharing options...
ezzzzzzz Posted August 29, 2007 Share Posted August 29, 2007 Justin, I sent you an E-mail. I'm willing to make full payment on the flange via Paypal assuming everything is still a go. I know how difficult it can be to get a machinist to start a one-of-a-kind project. They're usually very interested but have to keep the steady money coming to pay the light bills too! Link to comment Share on other sites More sharing options...
ezzzzzzz Posted August 30, 2007 Share Posted August 30, 2007 Paypal deposit sent. Thanks! Link to comment Share on other sites More sharing options...
JustinOlson Posted August 31, 2007 Author Share Posted August 31, 2007 I'm hearing that I will have a prototype this next week, then I need to verify the proto. Sorry that this is taking so long. I don't think I will be using this supplier in the future. Regards, Justin Link to comment Share on other sites More sharing options...
niceguy678us Posted August 31, 2007 Share Posted August 31, 2007 PM sent Justin Link to comment Share on other sites More sharing options...
JustinOlson Posted September 12, 2007 Author Share Posted September 12, 2007 Update... Link to comment Share on other sites More sharing options...
kj280z Posted September 13, 2007 Share Posted September 13, 2007 looks GREAT! Any updates on the plenum base? Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted September 13, 2007 Administrators Share Posted September 13, 2007 Update... ... Hmmm.. Looks like the port centerline has been biased slightly high necessitating removal of material from the roof of the port on the head when port matching. Taking advantage of another opportunity for improved flow, I like it. Link to comment Share on other sites More sharing options...
CarJway Posted September 13, 2007 Share Posted September 13, 2007 Wow... That looks great. I think I need one now... Link to comment Share on other sites More sharing options...
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