clint78z Posted August 16, 2002 Share Posted August 16, 2002 That's a pretty good price 240z turbo, I can't believe the price some places quoted me when I was looking into stuff like that. Hey James what amount of boost creep were you getting on your old 57mm hybrid. I doubt that I will get as much since you had a better intercooler. Getting a good wastegate is a must, I hear some of the lesser quality ones can fail due to the intense heat. Just conquered igntion gremlin last night, improper ground on GM HEI igntion module. The two plastic dowels had to be shaved off to make the case ground properly. Quote Link to comment Share on other sites More sharing options...
D83ZXT Posted August 17, 2002 Share Posted August 17, 2002 So Jeff... Which configurations are you going to use? It sounded like you had already made up your mind on your turbo. (62-1 w/.82A/R) I do hope you take James advice on the T66 v's the 62-1. While enjoying good conversation and a yummie BBQ, plus, of course talking "TurboZ's" with TimO. I told him how my question to "you" wasn't answered. (my builder tells me exactly what the CFM's,PSI Sweet spot,and efficiency level of%) So, he broke out the compressor maps, and showed me in black & white. If you want your turbo to make enough cfm to support 600 hp the 62-1 will not work!!!!! Its not even close. Look at the numbers on the compressor map. 70 lbs per hr flow, or approx 1,000 cfm can not be made by the 62-1. Well actually they can but at something less than 55%(or even less) efficiency. Those numbers are out of reach for the 62-1. They are not even within any of the efficiency ranges shown on the map, including the lowest. Looks like the T66 will get the air flow you are looking for at a decent efficiency of at least 70 lb/hr at 74% efficiency..... TimZ & James along with TimO. They are 100% right. CFM & Efficiency % Also, when determining your target cfm don't forget to consider the low ve of these engines. If you don't, I'm afraid you will be disappointed. Your head work I can understand, What are you going to do about your rings running @ 35PSI of boost??? Good luck and keep us posted Jeff PS...Thank-you all for sharing your knowledge so that we can better understand this go fast stuff Zoom Zoom Donna Quote Link to comment Share on other sites More sharing options...
D83ZXT Posted August 17, 2002 Share Posted August 17, 2002 Ooopps.. excuse me 30 PSI of boost I meant, sorry. Donna Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted August 17, 2002 Share Posted August 17, 2002 According to the formula, the 62 flows 70 pounds, so it should provide about 1000 cfm, which is enough for Jeff's target. The other distinction is I believe Jeff is after 600 flywheel hp, and he is not that far from it with his current set-up. The extra 20 pounds of air provided by the 62 should be sufficient, IMO. While I am not trying to fan the flames and create another Jerry Springer Episode, speculation was his EFI set-up and turbo could not support JWT's claim of 450 flywheel hp, yet he dyno'd 415 rear wheel hp. It may take some tweeking, but I am betting he gets the number he is looking for with the 62. Just one guy's opinion. Go for it Jeff, and lets see some big numbers. Quote Link to comment Share on other sites More sharing options...
TimZ Posted August 17, 2002 Share Posted August 17, 2002 Originally posted by Lockjaw:According to the formula, the 62 flows 70 pounds, so it should provide about 1000 cfm, which is enough for Jeff's target. The other distinction is I believe Jeff is after 600 flywheel hp, and he is not that far from it with his current set-up. The extra 20 pounds of air provided by the 62 should be sufficient, IMO. Donna brings up a very good point. After reading her post, I went and looked at the compressor maps. She's right - the 62-1's map doesn't even go to a 3.3 pressure ratio - the hightest point on the map is more like 2.9. Also, it's compressor map just barely touches 70lb/min (actually, it looks like it maxes out at 65lb/min to me), at it's lowest efficiency levels - just like Donna said. 62-1 Compressor Map The T66 does look like it has a much better chance of making 70lb/min at a reasonable efficiency, at a 3.3 PR. At least it's map goes there: T66 Compressor Map A couple of additional points about the maps: First, the cfm rating is referenced to flywheel horsepower, so we were not talking apples and oranges there. Second, the compressor maps tell you generically what the compressor will do. You then need to take into consideration the characteristics of the engine that you are attaching it to. The max flow rating for any compressor occurs at a specific, fairly narrow range of pressure ratios. At any give PR and intake temp, your engine will flow what it will flow - no magic here. If your engine will not flow that many cfm at that PR, then you simply never get to that place on the map, and the compressor flows less. In the case of the 62-1, for instance, it looks to me like the closest point to 70lb/min occurs at a PR of ~2.4. This is nowhere near the 3.3 that Jeff was looking for. At at PR of 2.4 (~21psi), Jeff's engine flows enough to make - ummm - I think it was ~415rwhp - remember? End of story. Please keep in mind that the efficiency ratings are not academic. Low efficiency = high heat, by definition. Planning for a high heat solution, when alternatives exist just doesn't seem very prudent, especially considering the compressor has not yet been purchased, and no cash has yet been comitted. Quote Link to comment Share on other sites More sharing options...
D83ZXT Posted August 17, 2002 Share Posted August 17, 2002 Thank-you TimZ. Now maybe some people will realize why I don't post much and have been a silent reader. When they do see my ZXT in person and come to realize that I have done 99% of my own work. I do enjoy it then.) Donna Opps aka: Turbo Guy that does housework first then goes plays on Z's http://zdriver.com/rides/detailride.php?cat=2&relIdx=6&vehId=843 Quote Link to comment Share on other sites More sharing options...
jeffp Posted August 17, 2002 Author Share Posted August 17, 2002 Guys, and Gals BTY Donna, VERY nice. I know you are looking at the data available to you on compressor maps and from what you have to work with you are correct, the T66 wheel will be much better. However, there is more there then meets the eye when selecting a compressor/and wheel. You also need to look at the slide ratios between compressor and turbine. You need to look at the speeds of the wheel @ it's desired PR and flow rates and match that up to the exhaust turbine wheel or you will have a doggy turbo. All of us see the information on the compressor maps, we dont get the diameter of the compressor wheels, and that is a factor also. We dont get the information of how this thing will react with the selected exhaust turbine and wheel. You need to look at the compressor housing and it's efficiency, and compair that whth the selected wheel also. All of these factors come into play when you put together a turbo application and hope to get it to do what you want it to do. Allot of the information out there is very sketchy at best, so we need to get better data on all of this stuff. I have been fortunate enough to get some inside information from the engineering departmants like Garret, data that is real life, turbo's that have been put together and tested. I am not going to say I am right and you are wrong, but I have had the opportunity to talk to a few people regarding what I have selected and this setup appears to be a winner. I have also been able to find a guy that is running very close to what I have put together and again this setup appears to be a winner. I guess where the rubber meets the road is how will it operate on my engine and that will tell all at the end of the day. additionally, if this does not turn out the way I think it is going to, I have the option to get the unit changed until I do get exactly what I want. I think 1000-7000 power band will do LOL This will be the third turbo on my car in a progression to the final build. When I reach that point that will be done, and the performance of the car completed. I realize there will be other cars that put out more power, have easier fuel management in the way of tuning, but when my car is to where I want it then hey someone wants more, then more power to them LOL I want 600hp at the crank and that is as far as I want to go. I could also do the work on the body of the car to improve it's strength and go farther, but I dont want a total drag car that I have to trailer and go to the track every time I want to drive the thing. anyway, thanks for all of your input on the matter, it's discussions likethese that make the difference with any build of these cars, you guys are the greatest. Jeff Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted August 18, 2002 Share Posted August 18, 2002 Good luck with the qwest to get your numbers. I have faith. Besides, you are charting new territory so I won't have to break in Clark on it. Quote Link to comment Share on other sites More sharing options...
clint78z Posted August 19, 2002 Share Posted August 19, 2002 Very true JeffP that those factors do affect how the turbo will respond on your car. 1)Diameter of wheel, moment of inertia. 2)A/R ratio, affects pressure drop and speed of gases, smaller is quicker response but there is a point where the pressure drop is too much affecting high volume flow. 3)Wheel design, number of blades, pitch, spacing Some of these variable can be hard to pin down what affect they will have on your engine package. The really good turbo guys know and won't tell, even then they can't always predict without testing. The simple fact is you need to pick a turbo that will flow enough air effieciently enough to produce 600hp. Why even worry about the other factors on a turbo that can't flow enough to make the power you want. I do think it is cool to see how far you can push something you already have. My jaw dropped to see Scottie push his stock T3 into the 12's. The T3 is not meant to do this, and died. Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted August 22, 2002 Share Posted August 22, 2002 i have no doubt jeff will get his 600 hp.the big question is what kind of torque curve it will have for street driving.a while back i was on a supra site and they had a hp/torque curve posted for a 700 hp supra.it was flat untill 4000 rpm.between 4000 and 5000 it came on like a light switch.bmw and renault made over 1000 hp with a 1.5 liter engine in f1.i am getting a bigger turbo worked on for my car but i hope it has good low end torque when it is done. Quote Link to comment Share on other sites More sharing options...
Guest Zcarsmakemyheadhurt Posted August 28, 2002 Share Posted August 28, 2002 Hey Jeff, I've seen your car on line a few times but I didnt know you didn't have such a big turbo. I kinda see that our goals are close but you already got thier. I just took off a E in favor of a 62-1 .60 housing and I must say I wasn't impressed. In all fairness I had a injector problem that left me far behind. I should have new set of 55lb in tomorrow and I will be testing my 60-1 Hi-Fi on a stage V wheel if you want to wait to see the results before comiting yourself to a set up...give me a call. Alex Costa Precision Machined Engines 1-800-665-0405 Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted August 28, 2002 Share Posted August 28, 2002 What exactly did not impress you about the turbo? 550's are probably not big enough for JeffP to hit his goal either, he was looking into 720's. What are the details on the test motor you ran the turbo on? Quote Link to comment Share on other sites More sharing options...
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