dusty

I'm a redneck. I have a 1996 lexus lx450 (a landcruiser with a $10k badge on front). I play with said machine in dirt. it has lockers at both full floating axles. I have a millermatic 175 mig welder and have welded heavy parts for my lexus like bumpers and sliders. (you guys dont know what sliders are) My truck is already slow with the 400lbs of steel i've added but will get slower with the 35 inch tires im planning. A year ago I began reading "maximum boost" by Corky Bell in preparation for a custom turbo build. Although this is a great book it does little to explain the specific little details of building the custom turbo like manifold construction and tube choices/materials. It offers little to the budget minded builder. I need help. I am humble. I have been searching this wonderful site for a couple days--pure pleasure.

1. what turbo to use: my landcruiser has the only usa motor offered. it is a 4.5L strait 6 cyl. dual overhead cam, 4 valves per cylinder, integral water jacketed oil cooler, with oil squirters below all cylider skirts. the motor makes a conservative 212hp and 175ft tq. redlines at 5000k. Has 135,000 well maintained miles and runs perfect. My landcruiser has the only usa transmission-a 4 speed auto. I rarely take engine above 3,500 rpm and at 80mph on higway the motor turnes about 3000 rpm (with 32 inch tires). I only want 6lbs of boost. I would love to boost down low but where I realy need the power is between 2500 and 3500 rpms as this when I am on the highway and need to pass people and climb mountains. A company in australia called safari used to make a turbo system for my truck but discontinued it. ($7000) This sytem used a t4 (not t3/t4). from what I have learned the turbo had a 46 trim and .84 a/r ratio (i dont know if this was turbine or compressor). I don't have much money and will buy ebay turbo. I have been lookinh at a t4 IhIRHBS with a comp a/r of .60 and a turbine a/r of .70. what a/r should I use for my needs? would these t3/t4 hybrids work or should I stay with a pure t4? If so What a/r ratios? Having had no experience, will oil cooling only (no water) work just fine from a reliability standpoint if I change with synthetic often. I have already installed a nice 2nd oil cooler. Are these $200 t3/t4 "buy it now" ebay turbos ok?. I am planning on using a integrated wastegate for simplicity sake-is that ok?

Tubing
I see you guys constructing your intercooler piping from aluminized mufler tube instead of that expensive silicone tube I almost purchased. Does this stuff rust on the inside at the welds over time?

Manifold
The landcruser manifold is a 2 piece cast header (3 cyliders each) with the collection from each of the 2 headers bolting via a 2 bolt flange to a "y pipe" that combines the gasses from the 2 headers to a single collection going to the exhaust. I am planning to unbolt the "y pipe" from the pair of headers and construct my own "y pipe" going from the 2 piece header to my turbo. By doing this I wont need to unbolt the factory 2 piece header from the engine. I see 2 problems in this constructiuon. First the 2 piece headers bring each bring 3 exaust ports to a single port. This single port flange bolts to the "y pipe" flange via only 2 bolts. Remember each half of the 2 piece header has its own flange with 2 bolts. I will fabricate (from weld els) a "y" header to bring the gasses from the 2 piece header into a single pipe going to the turbo. Are 2 bolts enough to hold these turbo flanges together in a turbo aplication? Should I just cut off the flanges and weld my "y" directly to the manifold (If I do this I have to remove the 2 piece exhaust manifold and all 12 bolts securing them-any of which may sheer?)

I will use no engine management for now as it has been found this engine can support low boost without a problem. in fact TRD makes a supercharger for the motor and includes no engine management

dusty

thanks jagojon3. I will do some reading on turbo selection. what of water cooling? I understand that water cooling will help the turbo live a longer life-other than that is there any reason to have water cooling? Are the cheaper name brand turbo's for $200 ok?

MAJORAHOLE

ever thought about twin-turbo?? two separate manifolds w/14b?

dusty

There are a lot of arabs in Saudi that run twin turbos on this motor with forged innards. these landcruisers develop over 700hp and do over 150mph. The 1fzfe 4.5L six has crazy potential.

so i have been reading my "maximum Boost" book (while at work) over the last couple of hours about turbo selection. at 5000 rpm's (redline) my motor moves 447cfm at a pressure ratio of 1.34 (5 lb boost). At 4000 rpm (hard as ill push it) and PR of 1.34 im moving 359 CFM. so I go to garrets web page to look at maps and they all use this lbs/time value instaead of CFM....what the hell!!!!! how do I convert?!!! arn't there any free turbo calculators out there that do all this work for you? I cant find any. If I'm going to pay for a calculator to show me all the maps, what one to buy?

Dusty

dusty

ok go figure-i search this site and i have converted cfm to lbs/min. so now I know that at 4000rpm (fast i will rev her) i am moving 25lb/min and at 2500rpm I am moving 15lb/min. when i look at the t04e compresessor maps using 5lbs boost (pressure ratio of 1.35) and connect the line between 2500 rpm (15lb/min) and 4000rpm (25lb/min) i see see that running such a low boost at these flow rates makes for an inneficient set up with most of the t4s. the 40trim is below 50%, the 46 trim is at 60%, but the 60 trim is better than 70 % at this speed-maybe ill look for 60 trim t4 compressors. 4000 rpm is important because this is where I would like to run on long mountain passes in lower gears. the t3 wont work as it doesn't seem to flow efficiently at the lb/min my motor moves and if i decide to get engine management and run higher boosts i will hit the surge line on most of the t3 maps. t04b s-3 looks like it would work. T04b v-1/v-2 looks real good at a low 5psi boost but if my boost goes much higher at all I will aproach the surge line with this compressor.

Ok so now I thinkI understand these compressors maps. but these different t04e maps im looking out are designated from one another by their "trim" (40,46,50,54,57,60) yet the turbos on sale also describe a/r ratios. Corky bell says in his book that A/R ratios are a way of "fine tuning" the basic turbo size. (I assume each trim a diferent turbo size?) He also says the right a/r ratio is something that is aften discovered with trial and error. I hate trial and error!!! I always error!! I understand smaller a/r ratios spool quicker due to fater gas flow yet can putter out at higher rpms (is 4000rpm high?) does the a/r ratio make all that much diff if i am going to use a say 60 trim t04e? Is there another turbo I should consider. I can read good and plug numbers but have no real world experience. please school me momma

dusty

ok I am talking again
in addition to answering the a/r ratio question above i gots more questions.

in my "maximum boost" book A/R ratios are referenced only in terms of turbines and not in terms of compressors. this confuses me even more.

please help me moma and make it hurt real bad