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  • #61
    I get your argument now...

    I never said it was a good street car. He was limited to 5psi because of the compression and pumpgas. At 5psi he is making ~270whp, and at 20psi he is making 490 whp. The car is a streetable drag car. Doesnt mean it is the best car for the street. The boy cant drive it on high boost and that is the only reason the car has not dipped into the 10's...

    BTW it is a rare (AFIK) Hybrid T-Series with a T3 Turbine side. I have yet to see another car with that on it. IMHO it is not the right size turbo for the car. He could run a smaller turbo and make more power everywhere. I was just pointing an example of BIG turbo and Big compression.

    Danny

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    • #62
      Originally posted by Turbomiata
      I get your argument now...

      I never said it was a good street car. He was limited to 5psi because of the compression and pumpgas. At 5psi he is making ~270whp, and at 20psi he is making 490 whp. The car is a streetable drag car. Doesnt mean it is the best car for the street.

      IMHO it is not the right size turbo for the car. He could run a smaller turbo and make more power everywhere. I was just pointing an example of BIG turbo and Big compression.

      Danny
      That is exactly what i was thinkin.... saying it is "sterrable" sounds more like it... 5 PSI on a T66 aint much and i agree that a smaller compressor would make it a much more "drivebal" car thru the RPM's!


      Ben
      MazdaSPEED6

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      • #63
        I am new to this probe thing, but I have been building cars since I was three(well, ok wrench fetching for my dad), and racing them since I was 15 or so. THIS IS JUST MY OPINION: You need to build your car right from the start. I'd get the heads machined for O-Rings, then build the bottom end, like a forged crank, connecting rods, and pistons. If you stay with 6-12 psi of boost you should be able to run 9.5:1 easily with premium fuel and a good tune up. Also boost does not always equal more power. If you have the same engine, same CR, same combustion chamber size, but engine A flows better than engine B, the the measured boost on engine A will be lower than that of engine B, but A will make more power than B, because it is more efficient.

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        • #64
          Hmmm Forged Cranks and connecting rods are easy to find for any of the popular ford/Chevy V8...
          But you must remember the KL engines aren't supported by any major tuners. So we are stuck with either $$$$ in custom parts or factory offerings.
          I do agree about engine air flows being important,
          but almost more important is turbocharger flow @ whatever PSI you plan to run. A Higher CR will make it more efficent, as will running more timing. But its a dangerous cocktail...use only with great caution.

          Running a Giant turbo (T66 What happened to the 60-1 or 62-1 ) and lots of CR (12.5:1?? I doubt it runs very well, if at all on pumpgas)... Has some merit, but has its limits of how far you can take it (on gas). Now switching over to methonol will let you take it much further.

          OT . JMO- Instead of slaping on big diesel turbos, I preffer to go with more technological advanced turbos like the Garret GT series.
          One specific model (T04BB I think) flows 72lb per min (vs 68lb/min for the T66) and will end up with a lower boost threshold on any engine (vs. the old T66). Believe me there was been SERIOUS advancements in turbos since the design of the T66.
          The probe is gone But its soul lives on....
          In a 71 240Z

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          • #65
            as i recall

            as i recall, a high compression engine will fight againt the boost produced by a sc or turbo. If using one one these two you want a low compressioned engine.

            nitrious is the only way you can go with a high compressioned engine. or have a high compressioned engine with no sc or turbo, use you basic bolt-ons.
            95 white probe atx 2.0
            MODS
            STUFF TO SELL!

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            • #66
              Re: as i recall

              Originally posted by white-probe
              as i recall, a high compression engine will fight againt the boost produced by a sc or turbo. If using one one these two you want a low compressioned engine.

              nitrious is the only way you can go with a high compressioned engine. or have a high compressioned engine with no sc or turbo, use you basic bolt-ons.
              SCC put 7PSI thru a Celica and it runs 11:1
              You need ot read this whole post and some other info before you go stating that NOS is the ONLY way you can go wiht a high CR motor, cause that is a myth, and a common one at that


              Ben
              MazdaSPEED6

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              • #67
                Re: as i recall

                Originally posted by white-probe
                as i recall, a high compression engine will fight againt the boost produced by a sc or turbo. If using one one these two you want a low compressioned engine.

                nitrious is the only way you can go with a high compressioned engine. or have a high compressioned engine with no sc or turbo, use you basic bolt-ons.
                i bet you didnt even read all of the posts yet
                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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                • #68
                  Once again this boils down to whoever's driving the car and/or the person putting money into the car. Higher static CR forces you to more finely tune the motor and limits the amount of total boost, but you get quicker spool and better off-boost throttle response. A lower static CR means you can boost higher, hence more fuel being burnt, and the tuning/ignition timing isn't as much of an issue, but you're not going to be seeing your potential in, say, city driving. Oh yeah, not to mention changing the intercooler size and piping, throttle body size, doing a P&P, etc. are some other variables that can be used to optimize the performance of your motor to personal needs, but you still won't make "the best" motor cuz the first motorhead that drives your car already knows what he'd change about it within the first 2 minutes of driving it.

                  Happy Tuning
                  .. thinkin' the $200+ in Dynomat would better go on a nicer car sometime in the future. I still want a damn turbo and good tires though...

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                  • #69
                    Just my .02 cents


                    When Ford released the 2.3L carb turbo from 1979 to 1981 they ran 6 lbs of boost with a 9:1 CR.

                    When Ford rereleased the turbo motors in 1983 the turbo motors ran 14lbs boost with a 8:1CR

                    Ford reduced the compression ratio to facilitate more effecient cylinder filling. The 8:1CR can hold more air in the same volume because cooler air is denser. If you are running a normally aspirated engine then yes higher compression is desirable but on a turbo motor the lower compression will make more power due to the better cylinder filling.
                    1980 Mustang 200 I6
                    1993 Capri XR2 1.6L turbo
                    1993 Probe SE 2.0L

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                    • #70
                      solution: Run the highest boost possible with the highest compression possible. -Darin
                      Lee Hubanks

                      As a political discussion grows longer, the probability of a comparison involving Hitler or the Nazis approaches 1.

                      http://members.cardomain.com/ntruder95

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                      • #71
                        Boost and ZE

                        I'm amazed at how many people you'll hear say, "Can't boost a ZE" I guess my philosophy behind everything is different. You either know cars or you don't. You know what will be a cause and effect. Not enough fuel = Boom. No Oil = Boom. Too much boost and not enough of either = Boom. Simple common sense thinking would help 90% of everyone not have any questions about the obvious. In any instance where raw materials are at stake, if you want more of something, you have to put more of the ingredients in. Air, Fuel, Spark = HP. I want more, ok.. Need more Air, Fuel and Spark. I want more HP again. Ok, Need more AIR, FUEL, SPARK. And guys, don't get smart about what I'm saying. I'm keeping this simple for the guys that don't understand. If you're baking a cake, and want it to supply more cake, you have to add more ingredients.

                        I want a 300whp Probe. So I bought 440cc Supra Fuel Injectors and a GReddy E-manage to control them. Plus a FPR, Vortech 12:1 FMU Walbro 255HP fuel pump. I wanted more HP, added more fuel.

                        Common sense will tell anyone that there are limits to everything. I know that my KLZE might beable to withstand 300whp. For how long? Who Cares! You have to expect set backs, blow engines, bad rings, blown head gaskets. It's called Racing! There are moving parts in the car. We have a luxury however. Back in the day, you would build and car and see what broke. Then pass that knowledge along. Well, its been passed along. So now we know that, "Hmm.. Ford built this car for a daily driver. Wonder if I can add 150+hp and still drive it daily and have it last 100,000+ miles?" And umm, the answer to that is "NO!" Not without re-engineering some things. Obviously no one builds and sells a new car with 200hp knowing that it can't take 201hp. Engineers take an enginer too its limits and back it way down. This is how you get cars that last 100,000+ miles. You make the engine and other components over powered for the weight to being with so they don't stress as much. Think about what we do to our cars! We basicaly screw up what millions of dollars in research and development went into. Do you think the work and engineering we do will be as successful in terms of making a car for every day driving? No! Again. This is my Racing Personality. Too many can't on the ProbeTalk forum. Here. I'll finish with my favorite saying. No need to talk anymore. I could type 500 page son this topic and never get through to some people and just waste my time and others so.. MY FAVORITE LINE TO SAY!

                        ANYTHING IS POSSIBLE WITH MONEY!!!

                        SPEND THE MONEY! BOOST YOUR CAR! ADD NITROUS!

                        It's all doable with money!

                        I will boost atleast 8psi to my ZE with a 35shot of nitrous. But I have some hellacious fuel mods and a GReddy E-Manage to Tune Everything. Will I blow this engine? Most likely if we don't get the tuning down right away. This is why alot of people stick with the same engine ratios and mods sometimes. They find they can get more hp/tq by tuning what they have and fixing the weak points then changing the whole setup around. I watched a $40,000 motor melt to pieces on a Dyno. It only had 1000 miles on it. What went wrong? Electrical problem caused detonation and fuel problems. BOOM! It happens. Just be ready for it. Expect the worse, and Live out the Best!

                        93' Probe GT KLZE ATX... Nitrous Express Wet Kit (50 shot), Eaton M90 Supercharger, TurboXS BOV, 3" Mandrel Exhaust with Magndflow Cat and Muffler. AEM FPR, Walbro 255HP Fuel Pump, Auto-Lite Gauges, 3 Gauge Pod, Custom Nitrous switch bracket, Dynotune Dual Purge Kit, Pacesetter Headers, 64mm TB, Sensei Hood, Shogun Bumper, Shogun Side Skirts, GReddy E-Manage, Supra 440cc Injectors, Custom Fuel Rail, Vortech 12:1 FMU.

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                        • #72
                          I think it's possible...
                          High compression engines are workable.
                          But since the higher compression generates MORE heat,
                          You need to do as much as possible to keep heat OUT of the intake charge.

                          BIG oversized intercooler with plenty of tube lenght to increase cooling effects (or an oversized air/water if you like dumping ice into it).
                          Efficent compressor, say 60-1 would be a great choice.
                          Efficent turbine wheel and turbine housing (IE not undersized),
                          A Stg 3 T3 turbine with an .81 A/R would be a good choice.

                          Now before the LAG police attack me, let me say that the high compression will help spool our efficent turbo.

                          Small turbos and small intercoolers are the reason why high compression engines explode (low octane too). People go out and purchase parts off factory turbo car that had low compression (with the ability to take a higher temp intake charge than a high compression engine) and expect 250-300WHP out of them. Psssss BOOM.
                          People defend these parts as well with comments like "DSM guys run 12s with them", but people don't relize that engine can flow big number and hold up to 400+HP...BONE STOCK. Not to mention people run 1800deg EGTs daily with NO problem. Not to mention handling higher intake temps than the KL03 or KLZE, not just because of compression but because it was designed to do so.

                          Also run the highest octane available (or that you can afford) and invest in a good knock sensing device as silent knock is the biggest killer of high compression turbo engines.
                          The probe is gone But its soul lives on....
                          In a 71 240Z

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                          • #73
                            Sorry for the lack of info in this post.

                            I just read this entire post from beginning to end, and all I have to say is that my brain hurts and I may or may not have learned anything.

                            Regardless, I think a lot of people appreciate the time and effort put forth into these replies and the information is priceless.



                            Mike

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                            • #74
                              i think GTRacer93 made the most sense out of anyone and their fancy formulas. you just do what you have to do. if you want more you have to give more of something. but it still doesn't help me choose the exact comp ratio to use. i wanted to go 8.5:1 but now reading all of this i think i want to go higher, but inbetween. maybe 9.2 and get benefits of both high and low comp. still not too high, and also low enough to take some good boost. the short lived FE3T, was 8.8:1. i'm sure they knew what they were doing, but i want some more comp for low rpms without boost for normal stop and go driving, and also high output at high rpms like 8K+. this will be a street car, with the potential to race. i'm over building, and not sparing much. just trying to make up my mind. after reading this most informative post, now i'm not sure at all what to use.
                              the good ol' F2T is only 7.8:1 and it does fairly well, and that's way lower numbers than anyone has mentioned in here and i see some ppl pushing a lot of boost through them, with the right mods ofcourse.
                              it seems to come down to everyone has their own preferences, and either engine tuned right will yeild great potential. but as far as lasting, is what i want to know. i want one that will last, yield great potential, and not the need to always having to tweak your settings to make sure you're at optimum so you don't blow something.


                              this is the 2nd best post i've read on a board, other one being gavin's all out suspension mods on mx6.com. this was way more informative though, but both just as interresting.
                              "Gone" but still around...

                              90 PGT, RIP
                              01 Dakota V8 4.7L 4x4 5spd
                              85 Supra mkII 5spd, new project

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                              • #75
                                You are on the right track

                                Originally posted by ProbeGT90R
                                i think GTRacer93 made the most sense out of anyone and their fancy formulas. you just do what you have to do. if you want more you have to give more of something. but it still doesn't help me choose the exact comp ratio to use. i wanted to go 8.5:1 but now reading all of this i think i want to go higher, but inbetween. maybe 9.2 and get benefits of both high and low comp. still not too high, and also low enough to take some good boost. the short lived FE3T, was 8.8:1. i'm sure they knew what they were doing, but i want some more comp for low rpms without boost for normal stop and go driving, and also high output at high rpms like 8K+. this will be a street car, with the potential to race. i'm over building, and not sparing much. just trying to make up my mind. after reading this most informative post, now i'm not sure at all what to use.
                                the good ol' F2T is only 7.8:1 and it does fairly well, and that's way lower numbers than anyone has mentioned in here and i see some ppl pushing a lot of boost through them, with the right mods ofcourse.
                                it seems to come down to everyone has their own preferences, and either engine tuned right will yeild great potential. but as far as lasting, is what i want to know. i want one that will last, yield great potential, and not the need to always having to tweak your settings to make sure you're at optimum so you don't blow something.


                                this is the 2nd best post i've read on a board, other one being gavin's all out suspension mods on mx6.com. this was way more informative though, but both just as interresting.
                                I think you will find that the answer lies within what you want. When you tell your engine shop what you want the car to do, they will say, less here and more there. I don't know if you're doing the work yourself but if you want a car that will last, consider that taking the highest compression route results in proper tuning of fuel mods. Lower compression is more forgiving. But if you have to boost all the time to get moving, then you will not lilke your car! Trust me. I know of a Turbo Supra that is fast fast fast and the guy hates the car. I beat him from light to light. Turbo lags too much. Once we hit open stretch though, I saw his tail lights from about 3 secs on till I couldn't see him anymore. If this your daily driver car I suggest you think about what Ford had the stock compression set to and up it a little from that. Then you'll know that a stock fuel system should be efficient enough if you stayed stock. But you're right, the only real way you have to go is to choose a middle level of compression 9.3:1 or something. KLZE 10:1, cams make it slow off the start. Compression makes it a beast there on though. I'm seen several boosted cars with 8.5:1 and the boost turned way up. If you can make the power with the engine and still be able to boost when you want it, why not take the extra power from the engine.

                                I just know that everyone makes things too complicated sometimes when someone just wants a simple answer as "Yes. if you want to maintain a daily driver and still beable to have the ability to boost a good amount, then go with a mid range compression".

                                So there you have it my friend. The answer usually lies within, you just want someone to back you up so you feel like you're right because you're unsure of yourself. You know the KL03 is a good motor and people have put 100k+miles on it with no problems other then leaking valve covers. You know the same block can go up to 10:1 and be run more then safe as it was in Japan. That tells you right there that you could go between those 2 compression and be just fine and probably better off then anyone running lower or higher compression then the 2 as tested by the car dealerships. Hope I aided you once more.

                                93' Probe GT KLZE ATX... Nitrous Express Wet Kit (50 shot), Eaton M90 Supercharger, TurboXS BOV, 3" Mandrel Exhaust with Magndflow Cat and Muffler. AEM FPR, Walbro 255HP Fuel Pump, Auto-Lite Gauges, 3 Gauge Pod, Custom Nitrous switch bracket, Dynotune Dual Purge Kit, Pacesetter Headers, 64mm TB, Sensei Hood, Shogun Bumper, Shogun Side Skirts, GReddy E-Manage, Supra 440cc Injectors, Custom Fuel Rail, Vortech 12:1 FMU.

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