How big is too big?
 

I am looking into turbos pretty seriously now. I am looking for about as much power as I can get and be streetable. Meaning be able to run 10-15lbs of boost and get the by about 4000rpms, and maybe run up to 20lbs for the track on race gas. As far as I can tell a 60-1 will get me about 400rwhp @ 15lbs guaranteed, right? Now how about a guaranteed 450rwhp @ 15lbs? Will this turbo do it or is it too large?


http://store.yahoo.com/cheapturbo/garrettto4r.html

that looks almost identical to a t-66 no?
its so hard to tell how much hp youll make
it depends on your porting compression tuning ignition fuel pressure its really hard to tell

with a big turbo youll be lucky to have 10psi by 4000rpms

list more info

Well its a fresh engine(13BT) with a large streetport; had compression all in the 90s with under 10 miles on it. Haven't gotten another test yet since I only have 300 miles on it. Will be running a microtech ltx-8, 720 primaries, 1600 secondaries, greddy fmic, anything else needed? I'm just looking for the potential of this specific turbo really. Especially compared to a 60-1. I just want a little more than a stadard 60-1 but pretty much the same spool up. Should I be looking into the 62-1?

do what i did. call sean or niko at aspec. i'm going with the gt40 turbo...bang for the buck with lots of topend

Get the GT35R (same thing as the 35/40) instead. You'll never be unhappy on a large street port to race port.

You can't escape doing a little math. You have figure out how much air you have to flow to hit your target and lay that over a compressor map.

I can tell you right now you wont see 450 at 15 psi on many turbos and that will spin up before 4k rpms. I loved my GT3540 but it wont make that power on pump gas and 15 psi. As far as turbos to make those #'s your talking just a few. While any Huge turbo can eventually do it you want it spooled by 4k RPMS. My Choice was the R85 kit from Reactive Racing and KG parts. Here is a dyno sheet. http://kgparts.com/R85.htm
Also the HKS TO4R kit. NOT just the Garret To4R but the HKS KIT EXCLUSIVLY can make close to that HP(different sizing) at that Boost pressure but its big bucks. The R85 is alot less.

I know I won't be buying a kit, but instead piecing my setup together. Now do they sell that turbo by itself? The sheet looks nice, but I dunno. Maybe I'd be happier with just a 60-1 over that. I mean at 15psi on a 60-1 I can see 400rwhp pretty much definitely right? And that boost at under 4000RPMs?



And Asleep, please explain to me exactly how I figure out how much air I need to flow and how to compare that with compressor maps if you would.


Oh and does anyone know how much this R85 turbo flows?

Ok now I've been looking into the T66 as well. How will that compare to the Garrett T04R?


http://store.yahoo.com/cheapturbo/turt66nonbal1.html

http://store.yahoo.com/cheapturbo/garrettto4r.html

When looking at the 2, the T04R flows more than the T66.


God looking for a turbo is pretty damn complicated, lol. Simply I want 425+rwhp on pump gas and by full boost by 4000RPMs. And want to be efficient up to 20psi on race gas for more power. Is that possible? Should I be looking into something like above or something like this?

http://store.yahoo.com/cheapturbo/t4b.html


Thanks for any and all help.

Hmmm if you're looking at serious power you'll have a choice of T88 / T51R / T78 i think the TO4R is quite cool too???

I had a t66 and now I switched to a 62-1
I only have 1300 on the new engine and its untuned so I havent gotten to see the spool much but I did see 5psi at 2800 in 4th thats the most ive boosted so far yesterday to see the spool. Remember this is totally untuned on a basemap and with my t66 tuned I got 5psi at 3500rpms its already 700 faster spool Im sure it will be over 1k faster once its tuned and I get rid of this huge ignition breakup

Please let me know how it goes for you. What is your exact setup and what kind of numbers are you looking for? Oh, and I am pretty local to you too. Thanks.

1994 RX-7 52k Miles
62-1 Turbo - HKS SS Manifold - HKS 50mm Racing Wastegate - HKS SSQV BOV - Modified Greddy 3 Row FMIC - Apexi PFC + Commander + Datalogit - New # GM 3 Bar Map Sensor + Connector - 50/50 Water/Alcohol Injection - Custom Spec Clutch with M2 Lightened Flywheel - 1680cc Secondary Injectors - 850cc Primary Injectors - Aeromotive Fpr - M2 Boshe Fuel Pump - Custom LIM - Crane Cams HI-6 Ignition - Magnecore 10mm Plug Wires - 4 BUR9EQs - Custom Air Intake (In Progress) - Custom Downpipe With Cutout - Midpipe With Borla XR-1 Muffler - Greddy SP Catback Exhaust - Greddy Pulley Kit - Greddy Profec B - PFS Boost Gauge - Pettit Aluminum AST - Relocated Battery - M2 Trailing Links - Gotham Racing SS Braided OMP lines - Koyo Radiator

Going for the max hp I can get out of it 475rw is probably what it will end up being if anyone will ever come to tune it

I'll tell you right now unless you get the HKS sized T04R it wont make 450 RWHP at 15 psi. The standard Garret T04R sold to the general public is not sized the same as the HKS kit. And it significantly makes less power then the HKS T04R. Steve Kan has tuned many of these and the HKS kit always kicks the shit out of the Home made T04R kits.
The sheet i showed you makes the power where you ant it and makes as much as you want all for a decent price. This is a proven solution.
There is a database of dyno sheets that list mods and turbo and boost level. If you want to compare. I believe its in a sticky in Single turbo section.
400HP is alot easier to attain then 450. So which is it your tryin to do?

400 is easy and there is a long list of turbos that can do it.

Well I think I figured out what I want exactly. At least 400rwhp @15psi BUT a turbo being efficient up to 20psi so I can run it on race gas and hopefully get as close as I can to 450rwhp. So what turbo would you suggest that will spool the quickest? What can a 60-1 make at 20psi? I was planning on this turbo a while back:


T04S 62-1 .70 A/R
Tang. divided turbine housing 1.00 A/R p trim for spool
Water cooled center
360 degree thrust bearing
dynamic seal

I think you'd be the most happy with a 62-1, its a great pump gas/street turbo.