kurinto

I am researching a turbo kit I'll be piecing together for my daily driver LS'd CRX. I wanted to go with a gt-series because of the fast spool and the gt28r was most tempting because it is $775 vs $1150 for the gt28rs.

My goal is 220 whp, what psi do you estimate I will need to run to achieve this? I will be using turboedit and a log manifold, the engine is stock.

I was plotting some numbers on the compressor map using my own calcuations and bluesi2k's turbo sizing program (thanks btw). I predict I will most likely be running around 10 or 12 psi (I did not factor in the pressure drop from the intercooler so I will probably seeing 8-10 psi at the manifold respectively).

My concern is the efficiency at 3500 rpms (farthest left dots for each color) seems to fall into around 65%. Is this reason enough to look for another turbo? Am I interpreting and using this graph correctly?

Since it is a daily driver I will most likely spend a lot of time under 4k rpms. But I will also have an intercooler, which would give me a few % efficiency. The gt28rs would put me at better efficiency but it is also $400 more...Anyways here's the graph:



Any input is appreciated.

used2baracer

throw that graph in the trashcan... you can make 220hp with a small t3 non-intercooled @ 6-8psi... why would you spend $800 on a ball bearing turbo and use a log manifold AND why would you spend $800 on a turbo and only want to make 220hp? Re-evaluate your setup/goals

kurinto

I want a ball bearing turbo because I want something that will spool very fast, I don't want to have to rev my engine out to make power. I don't want to make more than 220 whp in a daily driven crx. And I want to use a log manifold because I can weld one up myself for under $150. My goals don't seem to warrant a $600 manifold.

Tony the Tiger

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by used2baracer &raquo;</TD></TR><TR><TD CLASS="quote">throw that graph in the trashcan... you can make 220hp with a small t3 non-intercooled @ 6-8psi... why would you spend $800 on a ball bearing turbo and use a log manifold AND why would you spend $800 on a turbo and only want to make 220hp? Re-evaluate your setup/goals</TD></TR></TABLE>

Why do people keep saying that? A regular T3 will not spool anywhere close to a GT28R. Go drive a GT28R or GT28RS turbocharged Honda then talk.

poid

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">Why do people keep saying that? A regular T3 will not spool anywhere close to a GT28R. Go drive a GT28R or GT28RS turbocharged Honda then talk.</TD></TR></TABLE>

damn right, the GT28R spools extremely quickly and for the goals here will be an excellent street turbo.

used2baracer

if you're so interested in spool time, why use a log manifold? This idea always interest me - So what if you have a ball-bearing turbo and u spool up 500-700 rpm before me, your power band is still going to be between 4500 and 7000 just like my relatively large 50/63 t3/t04e with standard/journal bearings on my ls. All i'm saying is, save your money so you can put it where it will better benefit you, because you're gonna get similar performance. If I were you, I'd stick that money in a tubular/equal length manifold and a t3/t04b w/.48 turbine and 3" exhaust. You'll get full spool by 3500rpm for half the price of ball-bearing and put down 230 on probably 6psi...

Not for my benefit , but just to further prove my point, I have sitting at the shop a Freshly Rebuilt Garrett T3/T04b with .48 turbine housing for $350... that's $450 less than a ball bearing that will make similar power... pretty easy decision in my opinion


Modified by used2baracer at 12:41 PM 4/30/2005

.nate

I recently tuned a b18b with a gt28r on it and I was very amazed at how fast it builds boost. This turbo will make 15psi so fast it will make your head spin.

Def worth the money

y49crxsi

I must say, runs a lot better now too. For 220 you should be good at 10-12 psi. Only problem i see witht his turbo, is on the setup nate was talking about, we have a turboxs dual stage, and the turbo builds boost so fast, that the boost controller cannot bleed off the extra boost fast enough, and there is always an intitial spike to about 12psi, then it will drop down to 10. At least thats my theory, makes sense.

kurinto

gt28r and log manifold- $775 + $150 (thats a high estimate too) = $925

equal length manifold and t3 - $525 (cheapest dealer price i've seen on a t3) + $600 + $250 wastegate and dumptube = $1375

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Full-Race Geoff &raquo;</TD></TR><TR><TD CLASS="quote">
The results were quite astonishing, but do make a lot of sense. The log manifold spooled the turbo about 250-300 rpm SOONER than the equal length. </TD></TR></TABLE>

Looks like the log fits my budget and my needs...Granted the tubular would make more power up in higher rpm's but I only want 220 whp which seems VERY attainable with a log manifold. Why spend so much more money on a manifold for more all out performance when that is not my concern?

nonvtecD

The log manifold will spool just fine. Equal lengths only help make power in upper RPM's.

used2baracer

good luck with your kit

Tony the Tiger

Spool time...c'mon, stop comapring dyno graphs. Let off that throttle between gear shifts and we'll see how long it takes you to build back that boost.

The GT-series was mainly engineered to achieve instaneous boost response so anti-lag systems will not be too much of a necessity anymore. It keeps on spinning with minimal parasitic drag. Comparing a regular BB turbo to a dual BB turbo is a joke already, and you are comparing a regular non-BB turbo to a dual BB. I guess to each his own...

integrx

OT: but i have a HKS b-series manifold. I still haven't sold that sucker yet, kinda gave up after awhile. But anyways that turbo should be good to run with the LS

kurinto

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by used2baracer &raquo;</TD></TR><TR><TD CLASS="quote">good luck with your kit </TD></TR></TABLE>

Thanks

D-tuned

how about the log manifold your going to build with a regular t3 w/ internal gate. thats option is within your budget. you can use the extra money to pay for tuning. whatever you decide good luck and I hope everything works out for you

kurinto

I am pretty set on getting a gt-series turbo. I am also going to tune it myself with turboedit, just because I want to learn how to. Thanks for the suggestion though.

LeGeND4LiFe

How is your project coming along?

300whpOrBust

What manifold are you going to use with it?

I'm planning on using the same turbo for my civic, are you going to stay internally wastegated or go external? But i'll be using a B16, and my goals are around 270whp tops.

EJ1 wilcox

If you want to get the gt28r then get it!

If I had enough money to buy one I sure as hell would! But, if you are looking for a budget setup then go with a much cheaper turbo.

I kinda don't understand though why you want to invest in a ball bearing turbo with a goal of only 220whp. Like previously stated, you can make those numbers with a much cheaper turbo...

Why don't you just shoot for higher numbers? LoL... a b18b should be able to handle enough boost to make quite a bit more than 220 put that ball bearing turbo to work!

Sketch_hs

I can get you gt28rs for $1000, gt28r for $649

!

blundar

FYI: I had
-97 B18B in a 91 CRX HF.
-SSAutoshit manifold (with extra bracing)
-Tial 35mm gate
-T3 50trim .48 A/R hotside, .63 A/R coldside
-Starion IC
-3" DP, no cat, 3" Kteller piping kit, 3"in/4"out Apexi N1 muffler
-450cc/my boost code/turboedit tuned

With the 7psi spring, I had full boost by 3200 RPM.
With the 10psi spring, I had full boost by 3500 RPM.

The turbo spooled almost too fast to maintain traction in first, second, third. If you like spending money, have fun. My super-budget no-frills no-bling setup worked surprisingly well. Never dynoed (wrecked car), but on 10psi it hung/beat 1G DSMs on 19spi w/ small 16G, SRT4 on stock turbo/22psi so I'm inclined to believe it was at least 220whp.