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

[OneBadNA1NSX]

Great job David!!!! I'm waiting to check it out in person!

 

[cribbj]

Nice IC David, and it looks like it has the right stuff. Good luck with it!

Benji, every FMIC I've seen has been in front of the radiator and the the A/C condenser, and yes, it does affect the performance of both somewhat. But you shouldn't have to worry too much about it, unless you're still thinking about relocating to San Antonio :shock:

 

[Lextreme II]

Thanks RMS and John. I just drop off the heads earlier today and crossing my fingers to be done in about 2 weeks. It will get upgrade springs, oversize valves, stage II cams along slight mod of the head to accept 7/16 head studs. Porting of course. I am debating if i should use Cometic 2uzfe headgaskets or OEM Tundra Head Gaskets. They are both MLS.

 

[stevechumo]

Oh, man! I forgot my coffee. Next time we'll have some beer when time permits.

Your twin turbo intercooler is actually more efficient comparing to my single turbo intercooler.

 

[Lextreme II]

Side to Side looks better, but top to bottom works better.

 

[XR8tt]

The Cross flow one would cool much better ....
Much bigger area too....

 

[JustenGT8]

Longer core means more chance to shed heat but also means more pressure drop.... so you neeed to run more boost at the turbo to get the same boost at the plenum, which means more heat......can be self defeating but comes down to eff of core

Same deal with cross flow v vertical core. The beauty of the vertical core is the huge increase in cross-sectional flow area and therefore much less pressure drop. Comes down to whether the core eff is good enough to shed enough heat along the shorter core path....internal turbulator design becomes very important and you are looking at the high end $$$ cores.

I have run both and not much to pick between them for a street car. I would say it's a difference only a race team would be chasing. For a street car, it mostly comes down to packaging.

What you have to keep in mind is that for a street car the IC is mostly working as a heat sink so the MOST important aspect, after flow, isn't the eff of the core, it's the MASS of the IC...big heavy suckers are better. Why? because you aren't in a steady state heat exchange...all the initial heat exchange is from the core and end tanks heating up thus pulling heat out of the intake charge. The more initial heat sink capacity you have the better. The on/off nature of street boosting means the core can soak the heat and then shed once you are off boost.

On the track where you are always on boost you need good steady state heat exchange where the core can shed heat to atm efficiently continously.

This is why bar and plate is generally best for street and tube and fin is best for track work (tube and fin also much lighter with weight being a major consideration for a track car).

As with most things it's a trade off and you need to find the balance. For mine the best compromise for a street car that sees some track work is as large a bar and plate FMIC as you can fit. For me that was a 600x300x100mm core.

Hope that helps explain the pros and cons a bit

 

[XR8tt]

Exactly The vertical is nice if it can be fitted with end tanks etc and have enough room for correct sized i/c... With twins the vertical is better as the tanks combine the two entry points from turbo's...
I couldn't fit a vertical or didn't due to loosing too much i/c core, the lock mechanism for bonnet / hood needed modifying which I didn't want to do... I found it easier to make up a crossover pipe from left turbo to other side then down to i/c ....This way the i/c could be fitted within space available...

I find MOST U.S kits have small i/c compared to down under..
The Mustangs etc on www.turbomustangs.com most have small intercoolers...But then it depends power level, ambient temps, turbo efficiancy etc...

 

[stevechumo]

You guys are pretty much right on. My IC core is actually 4" and I believe it'll be good enough for up to 600 - 700 hp or a little more.

 

[JustenGT8]

pretty much ?

 

[curry]

Those manifolds are SEXY!

 

[stevechumo]

pretty much ?

How about much pretty? :silly:

 

[Lextreme II]

Got some update on my headers. Now I am waiting for some pipes for the WG and DP. Here is what I have over the weekend.

 

[XR8tt]

Sheesh I can't wait till I get my Shotblock back home...
About six weeks behind you...
Waiting for Kelford turbo billet cams from N.Z...

 

[Lextreme II]

Finally spent another $700 bucks on a Garrett T04S and arrived today. Bolt it right on and start working on the right wastegate. Now the only thing left are the down pipes and more tig welding and coating. Here are some updated pictures:

 

[cribbj]

Looking good David; that 2nd turbo really goes a long way toward making it look "nearly" finished!

 

[stevechumo]

Hot! Hot! I hope it'll be done very soon because I'd really want to feel how a 800 hp car is like.

 

[Fasteddie]

Lex,

you are relocating the alternator and airco, right ?

 

[XR8tt]

You'll just have enough fall for oil return ??

 

[Lextreme II]

You'll just have enough fall for oil return ??

Yes.....just enough height for the oil return drainage.

Lex,

you are relocating the alternator and airco, right ?

Alternator yes.... Airco.... deleted...