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reliability of NA vs turbo?

2974 Views 11 Replies 3 Participants Last post by  Yonaga
don't flame me if it sounds dumb but i am just wondering......i have heard how cars with turbos don't last....and that the turbos wear down... and sometimes need to be does that mean that the NA is overall more reliable than the turbo supras? how exactly does it all work?
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Don't take it as gospel, but you should expect 100K for a turbo and 200K for an NA before rebuild. My NA made 210 before the #6 cylinder got down to 100PSI, and although the others were still "within specs" at 150 (156 is Toyota's figure) I decided to rebuild the car I have owned since I bought it new 15 years ago. I could have done the valves alone and gone at least another 50K.

FYI, the turbo puts out lots more HP and torque, by using the exhaust gas to drive a compressor to push more air into the cylinders, and raise compression. It's pretty simple: Engine_Life = Running_Time/HP. Most turbo owners bump up the HP from stock, hence my 100K estimate. If you left it stock, you should be able to get 130K.
hmmm.....yeah that's what i figured. okay thanks a lot for info, that really helped...i guess i am just gonna try and find an NA supra then.

How about an N/A converted to turbo..........
Not counting the turbocharger itself, I would simply extrapolate. If the NA went 100K before conversion, it used one-half its life. If you turbo it, it has one-half a life left, but it’s now a turbo life. One-half a turbo life is 50K. So you should plan to rebuild the engine at 150K, and you still have another 50K to go on the turbocharger itself.

But, you would need to put on a new thicker gasket in order to drop the compression to 8.4:1, and while you had the head off you might as well do a complete top-end job. So, if your bearings hold up, you might push the car well past the theoretical 50K.

How heavy is your right foot?;)

We would all like our cars to run forever, but it ain't gonna happen. My mom actually put 350K miles on one engine in a Toyota Station Wagon. Lots of highway cruising at 55.:)
i also had another question. i was told that paying the high price tag on a supra isn't worth it if i don't get the turbos. i don't know a huge amount of turbos since i have never had one. and although i care about speed, with the money i am spending i don't want to have to do any major repairs on the car so early. so basically, what kind of power are you guys getting out of your BPU NAs? i only plan on doing i am wondering what i should expect then decide if it is worth it or if i should just go get another integra and fix it up. i had one before and loved but, but wnated to try "a better car." any thoughts?
I'm not sure about the mkiii, but there is a guy on the mkiv mailing list that has 150k on his stock twins. It really has to do with driving style and how much you abuse the engine. If you treat it good, it will most likely treat you good. I've seen a second gen. rx-7 turboII with 205k! Not bad for a rotary.:) The car looked like it was really taken care of, so he probably maintained the engine well too. Just goes to show.

As Kurt said, it really is all about your driving style. I would think you could expect an NA to do 0-60 in 7 seconds and a 15 second quarter. If you want lots more speed, (and these numbers are not "dog meat") you should think about NOS or Turbo. I don't know how old you are, but Turbos hit really heavy when insurance comes due.
thanks for the info guys. i am really leaning for the NA now. i'd say that my driving style isn't my main problem, as long as the car has ample power, i wouldn't drive it hard. i don't plan on racing it or even taking it to the tracks, but i don't want punks driving supercharged civics pulling up at lights and trying to smoke me, and succeeding :( . i would be able to beat them too, as i have done the whole driving fast thing and as long as the car is capable of beating these other cars, so would i. former punk integra racer here :)

but anyway, so the NAs shouldn't need rebuilding i am assuming irght? i am looking to get one with around 100k miles or less, and woudl like to take it to atleast 150 with regular driving. i would be using it for mainly freeway driving as somewhat of a daily driver. what do you guys think? will i be able to get atleast 150k (before any MAJOR servicing or repair) out of one of these assuming it hasn't been abused?

If you do highway driving, you should have no trouble. Change the oil and filter every 2-3000 miles. Get a good filter. I like Wix, but there are others listed on the forms, including Purolator One, and of course Mobil 1 filters. Stay away from "cheap" filters, including Fram. Follow the oil weight recommended in the manual for your area's temperature. If the owner has not been using synthetic, I would not switch after 100K. It will run through the engine seals like water through a sieve.

My 86.5 got to about 170-180K when everything needed replacing/rebuilding in 18 months. Alternator, Starter, Radiator, AC compressor, Water Pump, R&P, Brake cylinder, and Clutch Master and Slave. I did all these because I like the car, and having owned it since September 1986, decided I wanted to get to 25 years and qualify for Antique plates.:)
thanks for the info yonaga. that's pretty much the exact answer i was hoping for. i guess i am gonna try and find one in my range then. thanks for the help and wish me luck!
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