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Discussion Starter #1 (Edited)
Hello all. Normally I don't bother with reviews, because I was dealing with established and well reputed businesses or products, so there wasn't much point. I suppose the same can be said of Garrett, they make good stuff, so why the review?

Background on my car, I built it for road racing. Car has a built, dry sumped 1jz, old turbo setup was a Comp CT4-6265 0.70 dbb, on a tubular manifold. It made good power, and had a decent power band, but it was lazy on the street, and when it did hit, you sort of just got used to which direction it was gonna go sideways in, because that is what it would usually do. This was on a car with a great alignment, sorted suspension, and an OS Giken diff. The car was a lot of fun at highway speeds, but down low it was missing the "fun" factor that the stock twins had. In short, the throttle response was pretty awful.

Along the way, I got into autocross. Throttle response is a pretty high priority. I had a friend drive my car once, gave him some tips on how to keep it happy and going forward. He tends to be our fastest driver of the day in a middle ground Mustang, so the guy can wheel. His review of my car was both amused and bewildered, asking me how I manage to drive the thing as fast as I do, as its power is either EVERYTHING or nothing, there wasn't much in-between for him, he called it a "light switch" car. It wasn't until I took the car to a big-track autocross event that I realized I needed that "fun" factor back. In second gear, the car just had a dead spot between about 45 mph and 55mph, somewhere that you spend a lot of time in. There's only so much to be done with driver technique to overcome the deficiencies of a turbo engine... it was slow, no other way to say it.

So, after a lot of homework, comparisons, learning how to read and understand compressor charts better than ever, I had a choice to make. Go with a more established EFR setup, or take a chance on Garrett's newest offerings. My next choice came down to the housing. The 0.72 versus the 0.92 housing. It came down to a matter of 4 lbs/min of flow in the favor of the larger housing, so I went with the 0.92 housing. Spool versus top end... So, how did it turn out?

In a word, excellent. As a street turbo, this thing is absolutely awesome. Think stock twins spool and response, but with medium sized single power. In competition, I found that I was able to control the rear end much easier than with the old setup. I was able to spin the tires to the degree that I wanted. Definitely need to calibrate my foot again... If I were to floor it like I was driving my old setup, it would just fry the tires. Magic is, I was able to modulate the throttle to produces wheel spin as necessary. Loved it.

Size wise, it's about the size of a CT26, nice and compact. Unfortunately, it seems that v-band is about the only viable housing option currently. Garrett used to have a T4 option listed on their info page on this turbo, that it no longer on there as of today. Hopefully someone like ATP will fill in the gap.

Price, it's not cheap, but I have no regret in purchasing it. It gives me the throttle response I need for competition, and plenty of power. Dyno visit next month in Vegas should show us what the power band looks like. I suspect it will be pretty wide and flat, relative to a lot of comparable output turbos.

I have found my new default recommendation for 1jz owners. This turbo will be ideal for nearly anybody with a 1j, unless you're into drag racing and are chasing sub 10 second times. 2jz or 7m guys, this would likely make a nice option as well. I'm sure Garrett will be putting out something along the lines of a G30 in the future, that may be a solid option as well, if they indeed make such a turbo.

Edit: Apparently the G30 is now available. So there's more options in that small frame single market now. :)
 

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Discussion Starter #2
Update after a weekend of autocross on a medium sized track. This thing still rocks. If you're at low altitude, I suspect you'll be very happy with this same setup on a 1j or 7m. Might be perfect for a 2j if absolute response is what you're after.

What I was hoping to learn this weekend, is how this turbo responds to second gear autocrossing. Throttle response is everything in autocross (after handling and driver mods first), and you don't have the mechanical advantage that first gear provides, so you're relying on spool characteristics when in second. Is it a magical bag of unicorns? No, no it's not. However, my situation is probably a bit different than most, as I'm at 6500' elevation, so power and response are a bit down, we have to work for our air up here a bit harder.

That said? If you can learn to downshift to first, as appropriate (heel and toe is a valuable skill here), you'll manage. If you have vvti, you might be able to get by without a downshift. What's forcing me to downshift is what are essentially hairpin turns. You are not likely to see those on a road course or on the street. A nicely flowing autocross course is going to be a good time with this setup. I was seeing speeds of 60-70 mph with plenty of braking zone left. That's cooking on a cone course in a parking lot, folks.

What's that? You've never autocrossed your Supra before? I won't even ask what you're waiting on... if the thing is even somewhat reliable, you owe it to yourself to give it a try. It'll teach you skills and car control that you've never needed before, and will wonder why you haven't been doing this for years. :)

Future plans for me involve a vvti head swap, because I'm a sucker for wide powerbands relative to engine size, and a dyno session here in a couple weeks. Gonna guess now that it will put me around 460whp / 430wtq at around 18psi on pump gas. Will update you when I have more info.
 
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