fishtailfred

Correct forced, and to top that off, if longevity is an issue (less than 10000km) then you need to adjust your idiotic habits. It's easy to do burnouts and shit all day without destroying a clutch, and driving hard at the track is easy as pie for the clutch. vvega was right about my "normal boost" comment. normal is say 10 - 25 psi, and base is usually 40 - 45. you are right that you wouldnt adjust them. Provided your stocker has a vac/pressure reference, it is probably already 1:1, it definitely is if it was boosted stock. I only went to an aftermarket because the 044 would probably outflow a stock mazda one at idle. I didn't have time to gamble... FRPs are simple things, chinese is fine usually. OEM is better than chinese and you should use it if you can as they hold pressure after you kill the engine and prevent vapour lock. That is a good point you raise there about the pump running dry when you run out of gas. It would be nice to have a float switch on the surge tank to let you know that was happening and kill the feeder at once. Then again, you'll rarely go that low... so... What does your external low pressure pump flow? flow is everything for a lifter. Pressure ceases to matter. If it flows say 50% of peak requirement, it will likely be enough on the average, ideally you want it to flow 80 - 100% of requirement, and the high pressure one 120%+ Just make sure you have a wideband on your dash to keep an eye on the factory ecu... 510cc will be very marginal at getting the power you want, but should do the trick. If you find it going lean in the top end, it could be the injectors, but reality says, 19psi on a ca18 probably will be ok with them... just. The 044 can supply silly pressure if you need it, if you want to be sure there is a tested 044 you can buy that is rated to a very high pressure indeed. Same pump, but tested and checked to perform to the limit. I'll be raising my pressure as a temporary measure when I get back, but bigger injectors are in the works for me. The 044 can take it, but if you go too far, the injectors will start locking and not open. Certainly raising base pressure increases injector dead time and can be an exercise in futility. All EFI pumps are susceptible to running dry death, but none will up and die straight off, provided a splash of "coolant" goes through them regularly (read, sloshing tank). I'm glad you liked the link. I think I put that thread up on here some time ago, but, I don't know where it is now. Fred.

What makes you say EFI pumps are crap at pulling a vacuum? If you return the main pump to the tank, your lift pump needs to be BIGGER than your main one. combine that with the rate at which your lift pump is recirculating back to the main tank, and fuel temperature (which was never very important in the first place) is a total non issue. 250rwkw = 335whp = 400crank = as you said over 2 litres per minute at turbo bsfc. if it were NA, 2 would be enough. plus, you want some headroom. Seems to imply that it will pull vacuum and suck up fuel very well, certainly that is what I found with it as my lift pump. Not oversized at all, but should be good for what you want.

For 3 though, you need two pumps. you cant just use a surge tank inline with the main tank... See this : http://www.diyefi.org/forum/viewtopic.php?f=24&t=47 Scale it to suit your needs. 910 for "big" pump and any std oem external (quite a few hondas have ext pumps apparently) to push it to the surge tank. EDIT : what have you got for injectors? and engine management?

[*:25gavdfs]Organic full face with stiff springs and extra heavy duty pressure plate = ftw on the street [*:25gavdfs]if you are using X fuel you are making Y hp more or less. Those ratings are true at certain pressures. if you wanted to make 500hp from a 1.0 3 pot daihatsu at 50psi boost, the 910 wouldnt cut it. At normal boost levels, the 910 is a good pump. [*:25gavdfs](no baffle + 2.0surge tank) >>>> (baffle and no surge tank) you are on the right track

http://autospeed.com/cms/A_2986/article.html

etc.

Be VERY wary of using fittings on the head for oil supply to the turbo, most heads have a restrictor (again...) between block and head to ensure that A the mains and big ends are always well fed, and B the head doesn't flood and overflow. If you take your feed from the head and it runs low pressure because of a plug in the block to restrict head pressure/flow, you run exactly the same risks. It is possible that some heads have a different way of restricting oil flow and that high pressure is available in the head, but I'm guessing not many/if any because the headgasket would have to hold that pressure too. You need a fitting post oil pump and preferably post filter pre-head from the main gallery. You can get this by drilling/tapping or by Ting the pressure sending unit. My mazda block has a spare 1/8 npt fitting on the block which came in very handy for an oil feed Watch this : No restrictor, nice tight new turbo, note, oil pressure stays above 5psi for 30 seconds after the key is switched off!!! Journal bearings make an excellent restrictor indeed. The drains really do have to be good though, as a LOT of oil flows through them at higher revs. If the oil backs up to the seals, it will "blow" by them and create smoke. If the drain is good, that will not happen. Worn bearings could create an excess flow issue I guess, but the fix for that would have to be new turbo/rebuilt turbo, not a restrictor... Fred.

Forced is 100% right!! Restrictors are a hack to make up for poor drainage. I can link you a bunch of material on this, but just trust in jesus name and believe that you do not want a restrictor, and you do want the best drain possible. The trouble is that the restrictor restricts the most when your turbo NEEDS the most oil. Do not use one if you value your turbo. Also, BB units often/usually/sometimes come with a restrictor built in. They only need to be wet, journal turbos, like your mains and big ends etc, NEED pressure, not just flow. Fred.

I see new and/or synthetic oil in your future. In 2008 there is no need to wait for warmth for acceptable shifting. Box oil does wear out despite the fact no one ever bothers to change it. Changing worn out oil usually provides pleasing results

Key point here, is that the insurance company deals with it, not you. You just say "this happened, here are the details" and they either get the cash from the other insurer, or the other dude via court if they have to. They fix your car, and then collect the costs on your behalf. Most have this anyway.

No, what he said above.

Yeah, your insurance can fix your car and then sue/charge the other dude/boss/insurance and leave you out of it. That's usually the case anyway. Bummer about the car. Lessons learned. Last time I went to pass a car that was moving left but about to do a surprise right on the right I was doing nearly 130, same shit, fucking lucky to have lived, let alone dodged them! I've always been wary of pricks doing just that ever since. Only miles can teach you that shit.

Congrats on that build, looks pretty sweet indeed "happy now?" - sure am Particularly impessed to see EFI on that list. Do you remember talking to me about that at cams place once? Can't wait to see it in the flesh

Today is your lucky day, but I'm calling you lazy, it took about 15 seconds to find and quadruple reference this : http://www.lmnoeng.com/Flow/GasViscosity.htm Doubling the temperature appears to increase viscosity of air by around 6% All negligible... Much like the pressure pulse resonances which are NOT the same as venturi effect. I'm not going to explain that here though. Someone is trigger happy with the delete button and they (whoever they are, without exception) can get fucked. I'll share my information elsewhere.

And the venturi effect... which is less effective when overall pressure is higher from a poor setup. Wrong, that is what determines the pressure profile of the pulse. That pressure is acting with or against whatever is in the manifold at the time. Remove your pulsations and resonances for a second and concentrate on the MAJORITY of the effects at hand. = sheer restriction to flow. push the valve to a fixed maximum lift, pull the piston out and stuff a huge vac pump below it, then vary the air pressure between 0kPa and 400kPa and see how much air moves through that orifice. That is the majority of it. You can ditch all your resonances and expose you ports to the world and still make decent torque, or you can spend millions on research and get the figures up from 80% VE to 120% VE... (way less range than that) 80 is still greater than 120 - 80. Fred.

FFS, pull that cucumber OUT of your arse before it gets stuck in there and you end up on the xray teams wall of funny shit that walked in awkwardly... You are right that spooling a turbo is all about pulses. Particularly, it is about the VELOCITY of those pulses when they pass through the turbine, and the delta velocity between entry and exit. Of course you could build a big mani that spooled better than a small one. It's possible to build anything particularly shit if you try hard enough. Like all things, manifold design is a compromise. Take it to the extreme, perfectly smooth, optimal design, 1/4 of a mile from the engine and what do you get? that's right, poor spool. The pulses no longer carry the energy that they did when they left the exhaust ports. Drop a blob of splatter (i'm sure you can find a nice big blow out style one ) in a smooth piece of water. it is no coincidence that the waves are biggest and most most powerful in the epicentre. As for pulse timing, that is mainly relevant to NA setups. Much less scavenging goes on in a turbo manifold in boost. Consider the RPM of the turbine and you will see that relative timing of the leading edge of a pulse could fall on any particular blade, and of course, it doesn't matter which one anyway. As for google, believe what you want. google is for finding out about things that you don't know about. When you studied fluid dynamics at university, google is not where you get your turbo spool information Cucumber > OUT!!

I dunno about you, but I didn't read about it, I did it... Yes, but what determines how efficiently said pulses move?? Well bugger me, all these years I've been using MAP sensors to run my engines I was wrong and it wasn't working.... What do you suppose causes those pulses of flow on the intake side dude?? Thats right, the pressure differential between plenum and cylinder at the time when that valve opens. What do you suppose determines that figure? Average pressure and any resonant pulses present from geometry and speed. Average pressure on BOTH sides is a VERY good indicator of what is going on. It is not the whole story, BUT, it IS consistent, because the rest of the story is consistent and determined by geometry and speed. Which, if you want to measure heat in a resistor is ideal... (assuming your meter is RMS...) It's perfectly valid and a VERY good indicator of overall flow efficiency between air filter and exhaust tip... As for rust, ya don't think the fact that WATER is one of the main things you get in your exhaust has anything to do with it do ya? My thin wall POS manifold is sitting for two years right now. When I fire it up in another year to year and a half and cruise down the road and hit boost, I will not be too concerned about rust... why is that? The other main thing you get in your exhaust is CO2. There is next to no O2 left in that exhaust. Heat + O2 = rust. Take away either and you have slow slow rust. Also, I'm fairly sure that not too many people that just did a nice job on their custom mani would plonk it down in a puddle of mud in their cow shed for a month and hope for the best

I've gotta say, I have no respect for corky and that book. It is so full of blatantly wrong stuff it's near useless. It IS good as a break in book for boost noobs though What he wrote there sounded like it was written about VGT/VNT stuff? Twin scroll is good for spool for the same reason huge manifolds like mine are bad for spool. Internal volume and separation/lack of.

Four things : 1. the point of a turbo is to have the exhaust gases expand as they go through the turbine wheel. if there is a big open space before the turbo (read conventional single scroll and the merge area before it, the gases expand there and the energy delivered to the turbo is less. by keeping them together right up until the wheel, you keep velocity and energy up and keep restriction low. basically you can have top end and bottom end from a turbo that is twin scroll, but the manifold is more of a pain if you want to do it right. if you dont do it right, the thing will spool worse than a single scroll that is comparable. 2. no one complained when they saw my manifold and i said "1.6mm maaaaate". ALL manifolds should be extensively braced. even thick walled ones. the stresses on the studs are too high otherwise. if you don't brace it you are asking for trouble. conversely if you brace a 1.6mm walled one well (see my brace) there is NO stress on it at all. 3. on a good setup exhaust pressure will be close to intake pressure, on a shit setup, it will be MUCH higher. i'd love to see the REST of the setups that "just burst" and i bet there was some serious restriction between turbo and inlet valves and or between turbo and ex tip and or the turbo was a small one that was choking at higher power and providing immense back pressure and associated high ex valve temps and detonation prone operation. My ex pressure is about 19psi for 17.5psi of boost. I reckon thats pretty good. On a lousy setup, it might have required 40psi to reach that. 4. lovely work on that zetec? manifold very nice. Thats all folks

That's the point. You can slide them on purpose just fine. Piss easy. No worries. Ditto ANY car. However, when you are going REALLY fast (the true meaning of that seems lost on a lot of people) and pushing the limits NOT trying to slide, that is when they become dangerous and unmanageable. Beetles typically aren't capable of going fast enough to have issues Not a fan of the later mr2. I'd have an early 11 series one despite any faults it does or doesnt have though. When you push a nicely balanced car too hard with it neutrally balanced, it will be pretty benign. You can force a nicely balanced car into a state of imbalance and it will spin just the same. Even the best driver can't take a std mr2 or audi TT or or or or past the limit and get it back. Thats the point

I could hold a slide in my 54 just fine, and it didnt even have lsd! mr2's are dangerous. its all in the setup. typically heavy rear = hard to slide, once slides, cant be got back typically light rear = easy to slide, once slides requires great skill to get back 50/50 = dream to drive and even tyre temperature when pushing hard. bike engine based engines FTW!

its all rated to roughly 100 amps per 10mm for thermal reasons. as the size goes up that figure goes down. temperature is unlikely to be an issue. voltage drop is what you want to avoid. if it spins over fine with a fresh starter, battery and in warm weather, you might still be ok in cold weather with worn parts too. or you might not. if it cranks fast enough with worn parts in winter, you are golden. welding cable comes from 16mm through to huge. the stuff in dick/jaycar etc is 16 - 20mm when they call it "4 gauge" ... I like the industrial look, and its not heavy in the overall scheme of things really. True, but it's also way more resilient than the cheap shit at dick/jaycar. but less flexi. Indeed, note the braided fuel hose around mine and the massive quantity of cable ties holding it still. But, it's still not a full substitute. When your legs are trapped in the dash and you can't move and it starts burning on the side of the road wrapped around that tree you'll wish you'd fused it somehow. Great analogy. Probably wear and tear on the contacts esp if anyone was trying to switch something that was already trying to run. they aren't designed for that. yes, thats WAY too much, 25mm = 5/m 50=10/m or close to it. fred.

cough 0.6374 cough

Absolutely! I wasn't aware that such regs existed. even my dirty old ute had a return line on its factory carby setup.

dynos are all dodgy. dont trust them unless you were involved in engineering them. if you want to know the torque, back calculate from the power. the torque measured is probably directly that of the rollers including tyre to roller ratio, diff ratio, gear ratio etc. a sensible "loss" % for your box depends on its layout inside. vw beetle and fwd ones are in the 10% range rwd is 15 - 20 usually, but its not linear in any case, ie, if you have a factory rwd car it might be 20% at 150hp, but when you turbo that engine on the same box and make 300hp, you may only lose 12% sort of thing. the rwd setup is less efficient for two reasons, A hypoid drive diff B except for fourth where its perfect efficiency barring bearing friction you have TWO pairs of gears for each "gear" in a fwd or vw you only have one. the fwd has a helical diff too so its a hair better than the beetle. also, if you have a massively over rated box from the factory, you will lose more power to it. if its piss weak from the factory, you'll lose less. lol @ buying many alfas good luck keeping them all under control at the same time i need to pm you with my latest cunning plan too! fred.