Guest Anonymous Posted November 12, 2000 Share Posted November 12, 2000 Hi guys, need a little advice. Im having 2nd thoughts about the design of the dump pipe from my turbo. Have a look at it on http://www.usq.edu.au/users/degroot/240z/pages/new2_dur.htm the pic is 3 down on the left. Im worried that there might be too much heat induced flex in the outlet pipe from my wastegate that runs down to the main exhaust dump pipe. Because I want to show the car, I need something flexible that is neat. Ive seen some nice flexible sections on Page 148 or Corky Bells book, but cant find any of those over here in Australia. How have you guys found the flex affects things. . .do you think its going to affect my pipe or worse .. .my wastegate flanges?? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 22, 2000 Share Posted November 22, 2000 By the lack of replies, I assumed that no-one had anything like what I wanted. ..so I made one. . .should work like a beauty. Check it out here: http://www.usq.edu.au/users/degroot/240z/pages/new2_dur.htm#flex Quote Link to comment Share on other sites More sharing options...
Drax240z Posted November 22, 2000 Share Posted November 22, 2000 Looks good Simon. I looked at your problem and really didn't have much insight to offer at this time. I had a question about your FPR though. You made a rising rate FPR, correct? Could you outline the basic theory behind it for me? Thanks in advance, ------------------ "Gimme Fuel, Gimme Fire, Gimme that which I desire" -Metallica Drax240z 1972 240z - L28TURBO transplant on the way! http://members.xoom.com/r_lewis/datsun.html Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 22, 2000 Share Posted November 22, 2000 Hi Drax It was fairly simple, but a bit fiddly. I took a standard 280Z fpr, carefully cut the top off, and then made a cap to replace the nissan one. The cap I made has a port to connect to the manifold vacuum and a threaded section so that I could put a screw which pushes down on a washer that sits on the standard fpr spring (to add initial pressure). So if you start running out of fuel at top end, you can add pressure to the spring inside the fpr to increase your overall fuel pressure. The extra pressure will make you rich over the whole range, so It would need to be set when you do your initial dyno and not adjusted willy nilly. The final bit was making a clamp arrangement so the cap would be held onto the original nissan piece. Using a clamp system allows me to replace the bottom section if that part dies. Makes a cheap replacable FPR. Hope that helps Cheers - Simon Quote Link to comment Share on other sites More sharing options...
Drax240z Posted November 22, 2000 Share Posted November 22, 2000 Ah gotcha. I was thinking that you had made a rising rate regulator. (one that rises with boost levels) I've just realized that I don't need a rising rate regulator though, if I can adjust mine I should be able to meter it using the SDS. Yet another project to do before spring rolls around. Thanks Simon, great looking project BTW. ------------------ "Gimme Fuel, Gimme Fire, Gimme that which I desire" -Metallica Drax240z 1972 240z - L28TURBO transplant on the way! http://members.xoom.com/r_lewis/datsun.html http://members.home.net/drax77/newpage.html Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 22, 2000 Share Posted November 22, 2000 You should have a regulator that is referenced to manifold pressure..... Imagine you're running 35psi fuel pressure and 20psi boost..... That leaves you with 15psi fuel pressure! Not quite good enough eh? ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 22, 2000 Share Posted November 22, 2000 Hi again guys, It is actually a "rising rate" fpr. .. You'll notice in one of my early postings, I mention a port in the cap that is connected to the manifold, When the pressure in the manifold rises, the pressure is transferred through a hose to this port, it then applies pressure to the top of the diaphragm which assists the spring, so. . .if you have 10psi in your manifold, your fuel pressure reg then has the spring pressure. .plus. . the 10 psi. Sorry, I musn't have made it very clear in my description. Cheers - Simon Quote Link to comment Share on other sites More sharing options...
Drax240z Posted November 22, 2000 Share Posted November 22, 2000 Oh it was probably clear, I just didn't read it right or something. No worries. ------------------ "Gimme Fuel, Gimme Fire, Gimme that which I desire" -Metallica Drax240z 1972 240z - L28TURBO transplant on the way! http://members.xoom.com/r_lewis/datsun.html http://members.home.net/drax77/newpage.html Quote Link to comment Share on other sites More sharing options...
TimZ Posted November 26, 2000 Share Posted November 26, 2000 quote: Originally posted by simon-zbuild: Hi again guys, It is actually a "rising rate" fpr... so. . .if you have 10psi in your manifold, your fuel pressure reg then has the spring pressure. .plus. . the 10 psi. Simon... Careful with the terminology... "rising rate" and "pressure referenced" are not the same thing. What you have described is a pressure referenced FPR, not a rising rate. A rising rate FPR changes the fuel pressure non-linearly as the manifold pressure increases above atmospheric. For instance, a rising rate FPR should maintain a constant pressure differential across the injectors when you have manifold vacuum, just like the stock FPR. But, when the manifold pressure rises above atmospheric, the rising rate FPR will try to increase the fuel pressure by more than 1psi for each psi of manifold pressure - this is usually adjustable. so, at 10psi of boost, the RR FPR will have added maybe 20 or more psi to the fuel pressure. The purpose of this is to allow the stock ECU to still manage the idle and part throttle preformance, and simultaneously provide the appropriate amount of fuel through the otherwise undersized stock injectors when under boost. Also - you might notice that I said the FPR will "try to" increase pressure. In order to run higher fuel pressures than stock, you must be ABSOLUTELY sure that your fuel pump is capable of delivering the amount of fuel required, at the fuel pressures that you will be running while under boost. If your pump can't supply both the volume AND the pressure at the same time, there is nothing that the FPR can do about it. ------------------ Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 26, 2000 Share Posted November 26, 2000 Thanks Timz I must admit to not having known that one. Everyone I have ever heard refering to a "rising rate" fpr has been talking "pressure referenced". . and having read your reply, it does makes sense. Thanks for that. Cheers - Simon Quote Link to comment Share on other sites More sharing options...
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