Project Thread SC470TT (VVTi) Twin Turbo Lexus SC400 with 4.7L Toyota Tundra Engine

[4000GT]

Interesting on coating the inside of the pipes too... many of these coatings can flake slightly, obviously you are confident this one wont?

 

[Lextreme II]

It might, but these are the best and affordable option right now.

 

[stevechumo]

I agree with Justen. The high temp spring lock washers will get heated up and will eventually get flattened out after several hot runs. It happened to me. I used both heat treated steel and stainless steel and they're the same result. I used them on the downpipe. But they didn't loose because I torqued them untill they're flat out.

 

[Lextreme II]

Got some updates for you Lextreme folks. I got the Intercooler pipes done except the intake pipe. I tag weld the mild steel 3" pipes and will add two HKS SSQV BOV to it when they arrive. After that complete touch up and powder coating will make it look quite nice. The first few pictures tell the story. I drilled 2 4" holes turbo compressor inlets for fresh air behind the bumper.






I played around with the turbo inlet oil. After few trys, I decided to put little extra effort and few more bucks. I T off the oil pressure sensor and run the oil lines to the side of the fender and come up to the fire wall via a bulkhead fitting. I have seen some SC with dual oil lines and it was a mess. So I ran the lines outside of the engine bay and come up with a bulkhead. Here are some pictures.

 

[chanh55]

Simply amazing... kiss

 

[JustenGT8]

getting close

 

[cribbj]

Looking good David, don't forget if those are new style GT turbo's, you probably need some restrictor orifices in the oil supply lines, else you'll be burning oil.

 

[SC400TT]

David, nice oil feed solution...:headbang:

Ryan

 

[Lextreme II]

Thanks Ryan,

To spice things up a little. I picked up my TH400 transmission mount adaptor plate. It is made of 5/8" mild steel. This plate mount to the stock tranny support and Chevy tranny mount.

 

[XR8tt]

How strong are the third members ?? Toyota usually have strong diff's BUT sheesh she's going to have atleast 900 + Nm torque...

We had to fit 1mm restrictor in each oil feed line...

 

[Lextreme II]

I dont have GT turbos. I have the standard Garrett T turbos. I think single turbo might see some problems but twin will get half of the oil and should be ok.

 

[XR8tt]

If they are ball bearing you could ?? Its no big deal either way... Just be aware if it smokes out exhaust ? Just fit some oil restrictors..
I have twin Precisions on V8 Ford, had to run restrictors as well...
Seems oil pressure over 60Lb is there limit...
The oil feed was the same, taking oil supply off this location is the highest oil pressure point..
She'll be fine...

 

[stevechumo]

I never run a twin turbo system in my life so I'm not sure if the oil restrictors are needed. And I haven't researched about the oil restrictors and the benefit of them. I've been runing single turbo with no oil restrictor with no problem for years. I think the oil pressure and flow are always greater than how much the turbo can drain them out. So if you restrict the oil, then the turbo might be lack of oil. I may be wrong. :13:

 

[JustenGT8]

Yeah Steve you are wrong With plain bearings oil feed is rarely an issue and really you want as much oil pressure as you can get as the shaft is actually spinning on the oil 'cushion' not the bearing at all.

BB are a different kettle of fish altogether. They require much less oil pressure and have the seals to suit so if the oil presure is too high it pops past the seals and you have a smoke show.

BTW, the above will give you an idea of how overstated the spool up improvements of BB turbos are....it's mostly marketing hype as the differences are minimal. The real benefits come from the more modern comp wheel design and the much greater thrust loads the BB centers can takes. Both allow the turbos to run much higher rpm so a smaller frame turbo can produce higher hp.

 

[stevechumo]

Thanks clarifying this. I guess I'm an old school turbo guy...:wink1: It's time for ball bearing turbo, yah? I also read so much about actual new turbo setups and I haven't seen things like the ball bearing turbo spooling faster, thus reducing turbo lag. All they mentioned about spooling faster were always about the sizing and tuning. When they mentioned about the ball bearing turbos spooling faster, they were come from the turbo manufacturers.

 

[BigEv]

Octapus or not.. Here is the TH400 installed. Due the Rod Plate is 5/8" thick, my initial TC was made for 3/8". So the TC hub is little short. Time to go back the shop and extend the hub a little. Here are some pictures. Once I again, I have to mod the plate a little.

hay mate loving the build !!
i have a few questions for you, who did your adapter plate so the TH400 will mount to the 1UZ?? and you mentioned you had to mod the plate a little, what needed modding??
its just that i am currently looking for a new Gearbox option for my 1uz as i blew the 41LE that was behind it (crown).

also what made you choose a TH400 over say a TH700 or a C4??

Cheers
Evan

 

[Lextreme II]

hay mate loving the build !!
i have a few questions for you, who did your adapter plate so the TH400 will mount to the 1UZ?? and you mentioned you had to mod the plate a little, what needed modding??
its just that i am currently looking for a new Gearbox option for my 1uz as i blew the 41LE that was behind it (crown).

also what made you choose a TH400 over say a TH700 or a C4??

Cheers
Evan

Please contact CRS and ask for Glenn. He work with us closely. Anyway, I have some updates. Got my 4" elbow long legs. They are very hard to find and expensive too. Got them and cut them down to fit the turbo inlet. Getting fresh air from outside. The goal is to get cold air and keep them cold. Notice the pipe routings are kept away from heat source. Here are some pictures

 

[Lextreme II]

Guys,

I had a chance to install the transmission adaptor plate with stock SC400 cross member. Its a perfect fit. Here are some pictures.

 

[RedPhoenix]

damn this is going to be schweet.

 

[Lextreme II]

I will be ceramic coating my own headers when I get back from vacation.