Turbo Mani question.
Was looking at this picture
http://img138.echo.cx/my.php?image=hpim10216cz.jpg SOme questions 1. Whats the most popular size you guys use on the dia for those pipes. 2. Asuming it was a smaller engine say 1.3 Ltr 4 cylinder how small could I go. |
Re: Turbo Mani question.
when i built my mani i used 2" steel tubing with 1/8 inch walls. I had to smash the port side of the pipe to fit the flange but it worked.
|
Re: Turbo Mani question.
Hey I built that manifold. :) I used 1.5" Id schedule 40 weld els for that one. I decided to go that size due to the fact that when ovaled it lined up pretty close to the size of the head. I wouldn't go any smaller than 1.25"id. depends are you going to be using it on a bike?(high rpms) if so use the 1.5" or maybe bigger. I used mild steel because it was cheap. but you can get weld els in stainless as well. schedule 40 in that size is about .125" thick so it should hold up for a long time.
|
Re: Turbo Mani question.
You guys run 2Ltr cars right this is allmost half. No its still a car engine 1.3ltr 7000 RPM redline.
So Im thinking Ill get away with 1" pipe. Dont have space to run 4 seprate pipes so will run it as two pairs. Do all Inline fours have the same firing sequence. Anybody here own a Swift 13B |
Re: Turbo Mani question.
the one I built was on a 1.6L you could use two 1 1/4"id 90 degree els off of 1 and 4 and use two t's off of 2 and 3 and then just cut out where you want your flange and weld it on. your going to need a very small turbo. I think there was a suzuki turbo 3cyl or something that had a little ihi rhb32 that was pretty small. but a ihi off of a old subaru may be small enough for your application.
|
Re: Turbo Mani question.
i ran 1.25 on my d15
1.25 is pretty small as it is, 1 inch would be ubersmall |
Re: Turbo Mani question.
i used 1.5" ss 304 sch 10 from mccmaster.com, it works good, not the best to weld but it works, no cracks, just needs a little more heat to weld on than normal ss pipe, its like cast i think. but i use that on my ramhorns and logs.
|
Re: Turbo Mani question.
Originally Posted by gt350
Hey I built that manifold. :) I used 1.5" Id schedule 40 weld els for that one. I decided to go that size due to the fact that when ovaled it lined up pretty close to the size of the head. I wouldn't go any smaller than 1.25"id. depends are you going to be using it on a bike?(high rpms) if so use the 1.5" or maybe bigger. I used mild steel because it was cheap. but you can get weld els in stainless as well. schedule 40 in that size is about .125" thick so it should hold up for a long time.
|
Re: Turbo Mani question.
From my writeup on turbo manifold theory from pgmfi.org:
A blathering on exhaust theory, with an eye to turbocharged implementations, because I've never cared much for naturally asphixiated sissies. Substantially constant pressure turbocharging. Groupings of cylinders/banks of cylinders in such a manner that two or more exhaust events overlap (substantially). Characterized by constant, elevated mean exhaust manifold pressures. The up side is the turbine is fed with a constant supply of exhaust pressure/flow/energy. The down side is the high ambient exhaust pressure hinder the flow of exhaust gas and heat out of the combustion chamber/head. Turbine efficiency is high, runner efficiency is low. When set up correctly they work well-ish. Typically through the use of two things: long runners and precision merge collectors. The runners are expansive, to mute exhaust pulses, and long to prevent the exhaust pulse from bouncing off the turbine and returning to the originating exhaust valve before it closes (thereby foulling the chamber as the valve closes with a backwash of inert exhaust gas, and heat). A correctly designed merge collector reduces restriction where the runners merge; despite Full Rice Geoff's imbecilic blatherings about these being high tech and his invention, it's been common knowledge since before his birth that a shallow convergent angle of entry greatly smooths disparate flows together. It is appropriate to note at this point, that in some circles the verdict is still out on long vs short runner lengths in constant pressure turbocharging. I concur that the bulk of the gain in the refines constant pressure turbo systems is from a smoothly transitioning merge collector, but posit based on an ed-ju-muh-cated guess that tuning runner length and diameter to suit desired power band will result in some gains. Keep an eye on harmonics, and the relationships of EGTs, exhaust flow speed, speed of sound as affected by temperature, etc. Pressure wave aka shock wave turbocharging. Like, OMG! Groupings of cylinders/banks of cylinders in such a manner that no two exhaust events overlap (... substantially...). This *drastically* lowers ambient exhaust manifold pressure, which ensures excellent scavenging and flow of exhaust/heat from the combustion chamber at all loads and pressures. However, since each pressure pulse builds and is for the greater part spent before the next exhaust valve opens, the turbine is not fed a steady supply of pressure/flow/energy. Turbine efficiency is low, runner efficiency is high. When correctly done, port diameter is kept small to keep pulse strength as well as velocity high. Runner length is as short as possible, to avoid excess volume for the exhaust pressure to expand into as opposed to spending itself across the turbine. Spool time is enhanced, part throttle power and efficiency is enhanced, but WOT power suffers from inconstant pressure to feed the turbine. This is alleviated somewhat by the advent of split scroll turbines, but... no free lunches. So, yeah, I've been screaming that horseshit- er, horsepower, per psi is irrelevant for some time now. This is a good example of this. So you have to "turn the boost up" in order to hit the power levels of a properly refined constant pressure turbocharging system... mean exhaust manifold pressures have decreased dramatically, and exhaust manifold pressure for the bulk of any particular cylinder's exhaust event is decreased even further. Less heat and less stale exhaust gas is left in the chamber, and for a given setup running a particular flavor of fuel more power is made before knock sets in. This is seen a lot in diesels. Groupings of no more than three cylinders, with no more than 240 degrees of exhaust cam duration, in such a way that no two (sets) of exhaust valves are open simultaneously. This is also how the EVO 8's OEM manifold is constructed - that should give pressure wave turbocharging the riceboy stamp of validity. It's right up there with VTEC as the hot thing! Although this actually has some affect on performance instead of annoying exhaust noise. Sorry. Pulse converters. Pulse converters are, quite simply, ejectors or (DeLaval... heh...) nozzles that accelerate pressure waves before reaching the turbine. The idea is to convert an amorphous wave into a burst of focussed kinetic energy. So? Constant pressure application first: flow is accelerated, and the transmission of a particular pressure wave to an adjacent runner is prevented. Have you ever heard of an anti-reversion chamber? When used with pressure wave turbocharging, WOT turbine efficiency is greatly enhanced. At the cost of some runner efficiency under part throttle conditions - no sir, still no free lunch here. Afterword: Make your fancy-pants (insert Brand Name here) tubular manifold with cylinders 1 & 4 and 2 & 3 tied together, and feeding a split scroll turbine housing. Install ejectors as needed, if worried about hp/psi numbers, to impress magazine reading friends you will be kind enough not to introduce me to - unless they wish to race for money. Or you can use a valve (spare wastegate, hmm?) to marry the two collectors/scrolls at WOT or after a certain psi and have your quick spool and hp/psi at the same time. _________________ The Suzuki G13B is probably one of the strongest four cylinders ever produced. They have the same 75mm bore as the Civic - or the Suzuki Vitara we steal pistons from. The Vitara trick was originally used to drop compression on the G13B from 10:1 to 8.x:1 or so, and some of the crazy Puerto Rican guys have hit 300-375 whp with nothing else done. www.ssgti.com is for you, if you haven't found it yet. As for turbo size, it depends on what you are aiming for. G13B makes 100 hp at the crank, so let's place it between D15B7 and D16A6 with regard to what it will spool with good driveability. You could run a straight T3 with .48 AR turbine, dunno if you have them on your side of the ocean. I think an IHI RHB5 would be a disservice unless you only wanted (depending on the RHB5) 150-200 to the wheels. |
Re: Turbo Mani question.
What youve posted makes sence.
Im honestlly suprised at how amazinglly well the log manifold is working. We are runing a IHI RFB5 VI34. We removed the exhaust housing off it cause it wasnt starting to spool till 6000 RPM. ANd replaced it with a RHB5 IHI VI22 Exhaust housing (Half the size). Now I get boost at 1500 in Neutral with wheel spin if we launch at 3000 RPM. Redline is at 7000 RPM. And with the WG closed boost is crossing 20 PSI. THe fastest Suzuki in our country is runing in the 16s with a 70 shot of NOS. If I can run 13-14 seconds Id be king of the hill at least in this part of the world. Maybe we are refering to the wrong modell. Maybe its an earlier swift. It uses a 74mm piston with a 75.5mm stroke. THe Suzuki that runs a 75mm piston here is the Baleno. Its 1600cc and 100 BHP at the crank. WIth 16 valve. Mine is a 8 valver 65 BHP at the crank stock. So if I can get it up to 150 BHP it would be good. Honestlly I cant see how it could work any better than it is working now. But everybody keeps making fun of my log manifolds only cause they have seen better on the internet. We build multi section chambers for two strokes so shouldnt be hard to do a mani with indiviual runners. Just that keeping the a/c dosent give you a lot of space. Which is why we opted with the log to start with. |
All times are GMT -5. The time now is 10:59 PM. |
© 2024 MH Sub I, LLC dba Internet Brands