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  • #46
    Originally posted by hyc GTS
    It's a tricky game, there are many ways to play it.

    Anyway, intercooling is *extremely* effective. Remember that every one degree of temperature in the intake charge is reflected by one degree in the exhaust. Removing heat from the intake charge gives you obvious, directly measurable benefits.

    Like Corck said- Intercooling shouldn't be considered icing, its really part of the cake.

    Also another secret to the vortech kit...AIR to WATER IC!
    Very nice- but more $$$, complex, and space (2-3 gal. tank) than a decent air to air. And now with such devices as the N-tracooler, Air to Airs can be just as efficeint (just like loading an A to W with ice, will have to say C02 cost money, ice is cheap).
    The probe is gone But its soul lives on....
    In a 71 240Z

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    • #47
      I know this started out as a motor generic talk but i have wonder, IIRC the KLD has no cam overlap at all and the KLZE has some miniscule amount of overlap.... how does cam overlap effect boost levels you can run with otu accounting for CR issues.... like if someo ne were top place a ZE cam in a KLD w/ a turbo.... good/bad/indifferent?

      Ben
      P.S if i should post this as a new thread I will just let me know
      MazdaSPEED6

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      • #48
        The "Turbo" cam was mainly designed to take your money (when sport factory cams do the best job).
        Using a turbo with mild sport cams (like the KLZE) should work pretty well. It may let you run more boost, letting some turbos work more in their optimum efficeincy range...
        All and all turbo cams are at best a "black art".
        Truly depending on engine flow, turbo type/size, and luck (there are alot of factors that can make or break the concept).
        The probe is gone But its soul lives on....
        In a 71 240Z

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        • #49
          Unfortunately I've been gone for a week and a half and this is one of my fav. topics. I'm also at work so this will be a short response.

          I personally would prefer slightly higher compression with a reduced amount of boost to increase rev speed and retain a higher mid/low rpm torque while the upper end power/work will remain the same as the low comp. high boost engine. Correspondingly with the extremely efficient design of our chambers and accurate timing of dohc's it is more than reasonable to run 9.2 or 10:1 compression with an excess of 20psi and timing correction. I have stated in past posts that there are now hundreds of people running 4v modular fords with 10-20-30+psi that have very similar comb. chambers and 10.5:1 compression ratio while the 2v mod motors have bad detonation problems with this same setup. Now I'm not saying anyone should do this without extreme precautionary measures, just stating that it has been done many times over.
          1994 PGT MS2 LC-1 370cc 190lph KLZE intake ported heads Turbonetics T4 2.5" Magnaflow STS MX3 flywheel ceramic clutch, 355fwhp ** sold
          1980 Fairmont 4-door, S472, Megasquirt, 351C, 678rwhp.
          2003 Mach 1, FR500 engine, 372rwhp w/out spray.
          2003 Escape, slow.

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          • #50
            nice reading.....this will be sticky
            Life isn't like a bowl of cherries or peaches, it's more like a jar of Jalapenos ....
            What you do today, might burn your ass tomorrow.

            Pearl '92 Audi //S4 GT3071R, running 27 psi
            Lava gray '14 Audi //SQ5, Chipwerke, 034 Intake Pipe
            For PSP Awareness click here

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            • #51
              Originally posted by rurockn
              Unfortunately I've been gone for a week and a half and this is one of my fav. topics. I'm also at work so this will be a short response.

              I personally would prefer slightly higher compression with a reduced amount of boost to increase rev speed and retain a higher mid/low rpm torque while the upper end power/work will remain the same as the low comp. high boost engine. Correspondingly with the extremely efficient design of our chambers and accurate timing of dohc's it is more than reasonable to run 9.2 or 10:1 compression with an excess of 20psi and timing correction. I have stated in past posts that there are now hundreds of people running 4v modular fords with 10-20-30+psi that have very similar comb. chambers and 10.5:1 compression ratio while the 2v mod motors have bad detonation problems with this same setup. Now I'm not saying anyone should do this without extreme precautionary measures, just stating that it has been done many times over.
              4v Heads by their nature are more detonation resistant. More quench area, as well as less combustion chamber surface area [in general].

              Thanks for making it sticky Raf. Again, this is one of my favorite topics.
              David Coleman #1891 - Fastest of any Gen @ MMIV:
              1993 Mazda MX-3 GSR Special Edition - PINK POWA! - KLZE powered!

              The Idiot Post Patrol :
              Fighting ignorance one post at a time [this public service brought to you by Nikki and David]

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              • #52
                Well, I havn't had time to read this entire post (I will later), so I'm not sure if anyone had mentioned this or not...

                One reason why lower comression and higher boosted engines can make more power is because on the intake stroke, the manifold pressure is pushing on the piston, creating work. more psi = more work. look at a P-V (pressure vs. volume) diagram of two different boosted engines. you'll see that the intake stoke will create more + work with the higher boosted engine.

                I think Andrew already mentioned about compressing air and it's affect on temps, right... with higher boost, the intercooler can cool more of the compressed air. and with less compression in the cylinder, it will not heat up as much in the cylinder as lower boost + higher compression...
                Daniele DeFranceschi
                95 PGT Turbo - RIP
                01 JRSC'd Lude

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                • #53
                  OEM Turbo engines use low compression because they are afraid of some idiot running PEE water though it.
                  OEMs have to be almost bullet proof. So that is why you can pump up the boost some on most factory turbo cars without changing anything else like the turbo and IC.

                  I'm using this as an example...
                  In Japan, the late model MR2 turbo has 9:1 CR STOCK.
                  They where able to do this because they have decent fuel available.
                  The New Toyotas are great example of a detionation resistant 4V design. The 2ZZ-GE (cel. GTS) has 11:1 CR but will run on pee water without beating its self to death. I think the other secret is the VVT-i, running lots of overlap and lift seems to take the edge off of the CR. The 8 psi boost numbers are SCARY on the 2ZZ-GE

                  An 11:1 engine with boost and pump gas...who would have guessed?
                  CRs are starting to climb back up to where they were in the 60s...WHY? Can't be the gas (it still sucks)...I think you know why. I think the 2Ver has gone the way of the dinosaur, with the 3Ver looking like the 60s.

                  The future seems to be direct injection, high compression, and VNT turbochargers (sources from Honeywell/Garret say the BB turbo is yesterdays news, the VNT is tomorrom). Just think...no more discussions over the correct A/R ratio and the term lag will be long forgotten (thank god )
                  The probe is gone But its soul lives on....
                  In a 71 240Z

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                  • #54
                    ANOTHER FACTOR is you may be able to make an engine with High compression and a reasonable amount of boost aka 10psi or so, with some work and knowledge but you also have to realize how much stress that puts on the engine, ex head gasket, rings, etc. and longevity of the life of the engine

                    Thats why I had wiseco make me 2619 forged alloy pistons with compression of 8.7 to 1 with a 11mm dish. They are 20 over bore to give me a larger engine cc's. I figured so many people see these magazines of super imports and high boost but don't realize that almost all of us on this board (some exceptions) do not have the money nor the sponorship to support goals of high comp and boost to boot! Not to mention the fact that they don't mention in the articals that the engine gets rebuilt on a regular basis or that the car is a trailer queen and has only seen dyno's or less then 1000 miles in 2 years. Why do you think so many people have problems with aftermarket turbo's civics, probes, you name it. Realize that lower compression with 10psi is less taxing on your engine and will give it a much more reliable life. Since most of us don't have $$$ coming out of our butts, pick and reasonable boost level (mine will be 10psi street and 15psi track changed later after tuning) and lower compression. Don't think that you can make your car last long on high compression and high boost. Some trades must be givin to the boost gods if you plan to not have to rebuild often or spend lots of mulla to prevent rebuilds. to boost it's a bizz-atch


                    p.s. to help with low rpm increase in the begining of launch I plan on having a somewhat lightened flywheel and I'm debating on twin for smooth overall curve, not to mention top end rpm redline will be much higher do to the forged internals and millennia S rods and lower compresion so i'm hoping redline to jump to above 8200 rpms
                    1982 FIAT SPIDER 2000. Rear wheel drive classic fun!

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                    • #55
                      Originally posted by geck0
                      ANOTHER FACTOR is you may be able to make an engine with High compression and a reasonable amount of boost aka 10psi or so, with some work and knowledge but you also have to realize how much stress that puts on the engine, ex head gasket, rings, etc. and longevity of the life of the engine

                      Thats why I had wiseco make me 2619 forged alloy pistons with compression of 8.7 to 1 with a 11mm dish. They are 20 over bore to give me a larger engine cc's. I figured so many people see these magazines of super imports and high boost but don't realize that almost all of us on this board (some exceptions) do not have the money nor the sponorship to support goals of high comp and boost to boot! Not to mention the fact that they don't mention in the articals that the engine gets rebuilt on a regular basis or that the car is a trailer queen and has only seen dyno's or less then 1000 miles in 2 years. Why do you think so many people have problems with aftermarket turbo's civics, probes, you name it. Realize that lower compression with 10psi is less taxing on your engine and will give it a much more reliable life. Since most of us don't have $$$ coming out of our butts, pick and reasonable boost level (mine will be 10psi street and 15psi track changed later after tuning) and lower compression. Don't think that you can make your car last long on high compression and high boost. Some trades must be givin to the boost gods if you plan to not have to rebuild often or spend lots of mulla to prevent rebuilds. to boost it's a bizz-atch


                      p.s. to help with low rpm increase in the begining of launch I plan on having a somewhat lightened flywheel and I'm debating on twin for smooth overall curve, not to mention top end rpm redline will be much higher do to the forged internals and millennia S rods and lower compresion so i'm hoping redline to jump to above 8200 rpms
                      when you get all your parts, get your rods shotpeened, (its like 7 bucks a rod) and get your assembly balanced !!! that way you can take it up to 8200 without worry
                      Life isn't like a bowl of cherries or peaches, it's more like a jar of Jalapenos ....
                      What you do today, might burn your ass tomorrow.

                      Pearl '92 Audi //S4 GT3071R, running 27 psi
                      Lava gray '14 Audi //SQ5, Chipwerke, 034 Intake Pipe
                      For PSP Awareness click here

                      Comment


                      • #56
                        Originally posted by FRCFD6


                        when you get all your parts, get your rods shotpeened, (its like 7 bucks a rod) and get your assembly balanced !!! that way you can take it up to 8200 without worry
                        btw this is geck0 posting at ty's house
                        I understand this idea and since i work at a machine shop, it would be free-The problem with shotpeening the millennia rods is the fact that the wrist pin hole has a brass bushing that is sized to fit your wrist pin and if you shotpeen the rod you have to press out the bushing then replace it with a new one after you shotpeen, leaving the original one in during the peening to keep the mating surface on the rod the right size.

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                        • #57
                          One Thing that everyoe here forgot to mention is timing.. I will cut and paste clip from another thread...

                          BTW To whomever mentioned that a supra on 6.9:1 compression and STOCK TURBOS MADE 900WHP you were fooled. The stock exhaust housing on the twins cant even flow enough air out without even on a 300 shot of N20 to make that much power. THe compressor sides of the stock twins cant flow enough air for 900hp even at 30psi each (if they can spin that high)

                          Here is the clip..


                          :quote:
                          Here is the deal with compression.. Low boost and high compression will make more power than low boost and low compression. High boost and High compression will not allways make more power than High Boost Low compression. The reason is many of things. You have to find a happy medium with a car. It depends on the flow of the head, intake manifold, exhaust manfiold, and the turbo at hand. Many of times with the lower compression you can run enough timing to more than make up the power, without detonation, and guess what your egt's go down. Many people do not know but retarded timing is just as bad for raising egt's as running lean is. 2* of timing on my car can drop egt's almost 75*C. This is where it comes to play.. When race gas (104 octane or higher) things stay the same except with more compression, timing, and boost. Methonal is a whole other ball game with stratospheric boost and compression levels.

                          I know of a low 11 sec street honda that runs 12.5:1 Compression and a T66 Turbo. Only about 5psi on the street but that is enough for high 12's. For race day he runs 20psi with C16 race gas. Has gone through is share of headgaskets though.. (bad tuning IMHO) Turbo spools great with that compression though.

                          Enjoy

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                          • #58
                            Originally posted by Turbomiata


                            I know of a low 11 sec street honda that runs 12.5:1 Compression and a T66 Turbo. Only about 5psi on the street but that is enough for high 12's. For race day he runs 20psi with C16 race gas. Has gone through is share of headgaskets though.. (bad tuning IMHO) Turbo spools great with that compression though.

                            Enjoy
                            I have a hard time believeing that a <2L motor can effetively spool a T6 and even if he does he is an idiot casue a T66 is way more compressor than he needs for 5 PSI!!!!! ALOT of turbo supras/RX7's run the T66 as a single turbo upgrade and never have i heard of one doing it w/o a 50 shot ot help spool... mind you a supra runs 3.0L over a hondas 2L...


                            Ben
                            MazdaSPEED6

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                            • #59
                              Keep in mind Ric Stephens (aka purple minimonster 400hp miata) runs a T66 on his car. He doesnt get full boost tilll close to 6000 rpm.. Honda's dont get boost till about then also (as for drag cars) but it doesnt matter because they rev to over 8,000 and stay above there after each shift. Once Ric's new head is done he will be able to take the car to over 9000 and the T66 will be the best turbo for him. Trust me There are many of small displacment motors running big turbos. I know of a 2.0L DSM that is running a T72.. Its all on the flow of the motor, design of exhaust manifold and A/R ratios.

                              Keep in mind almost ALL of the Quick Class cars are running a T series turbo.

                              Danny

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                              • #60
                                But he claimed it was a street car!!!! Your talking drag only


                                Ben
                                MazdaSPEED6

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