I am trying to decide which single to go with. I keep reading about application, drag, street auto cross, etc. The thing I dont understand about the application regarding weather or not a turbo is streetable is basically the spool up time and turbo lag. The bigger turbos have more lag I understand, more exhaust gases required to spin it. What I dont understand is the rpms people are driving at to get turbo lag. With all of my mods and the stock twins, I am probably running around 340 whp. To be in my power band though, like everyone else with the stock twins, I have to be above 5000 rpms to have any sort of power. Nobody is shifting at 5000 and hoping for power in the next gear, you have to shift higher, that being said everyone when driving aggressive is always above 5000 rpms. All the big turbos have surely spooled up by 5000 so whats the big deal. Even if you were tracking the car you would never come out of a corner at 2500 rpms, if you did your wasting power, as you are in the wrong gear. Please help me here. There are ads out there from A - Spec for hp ranges in the high 300's for their smaller kits. I have also read ads from Sr Motorsports that have a streetable
600+ whp kit, so what gives. I understand a ported motor, stand alone, and fuel needs change with hp but why is the "streetable" discussion so important. What am I missing. Here is my mod list. My goal is to have a pile of hp, not neccesarily the most but alot. I would like to runs 10's, maybe hit 200 mph some day, which turbos are reccomended. A friend has suggested a GT35R would a GT40 or a GT42 be better, if so, why? Also has anyone tried this streetable 600 hp kit from SR. Any input would help, thanks.

I run about 13psi on 94 octane
pettit ecu upgrade
large m2 i/c
electric i/c fan
crane ignition with new wires
street port
Cosmo fuel pump
tial blow offs
twin k&n filters
hks sequential boost controller
blitz turbo timer
greddy down pipe and full exhaust (no cat)
lightweight battery
lightweight pulley kit
stainless ic piping, greddy elbow to throttle body
silicon vacuum hose upgrade
kaaz 4.33 lsd
b&m shift kit
eibach springs
nitto 555R 255's in the rear

 

Like anything " street-able " is matter of opinion. Street- able to me means a broad torque curve, not a peaky powerband.

 

Cmon guys give me some feedback, ther must be a few guys out there that have experienced these laggy turbos vs the quick spoolers, what do you prefer and why.

 

Part of it is the efficiency range, if you have a great big turbo, you really aren't utilizing it's performance gains unless you're gonna run 25+psi. To do this you need injection or race gas. Some people do run gt42's at 12psi etc though.
I like how my turbo is fully spooled by 3800 rpm, and I don't have to rev the **** out of it to get full boost, it makes it more fun tooling around town. If I was just going to be doing highway pulls, then I would want a bigger turbo. You need to read more and find out what will be best for what YOU want.

 

I gues what i am ultimately after is a setup with alot of power that wont make the car hard to control. I dont want to down shift into 3rd punch it and spin like an 800hp supra. I want more power than your average guy, I wanna smoke done up srt 4's, i wanna smoke vettes, not so much off the line but on a rolling start. It is also very hard to be specific with what kind of power i'm after because I dont know the difference in feel between 300 whp and 500 whp. If there are any guys out there that have made the big jump to the high 400's, tell me about your experience, thx.

 

Since you are running sequential, you should have decent power below 5000rpm.

My stock intake port, mild exhaust port non-seq at 15psi had:
200 at 4100
250 at 4600
300 at 5000
347 at 6500 on a PFC!

Now consider that the stock engine had about 225 at 6500 and I have that at about 4300, what are complaining about.

The Pettit ecu is killing your power. Go to http://www.catenet.net/dyno.php and look at some dyno curves for similar mods as yours.

Go GT35R T4 or GT500R for good street power.

 

The catenet.net site is the original site (hosted by my buddy Frank). The link in my signature is much more updated, but it's currently down since I'm moving

Is your goal to whoop some people in street encounters? Sounds like it
Or maybe your goal is organized drag racing or track racing?

For dishing out street whoopings....

My car has 400 rwhp with a T04S at 1 bar. I've never come across a car on the street that had much of a chance against me (although I know faster cars are out there heh). Keep in mind that 99.99% of the cars on the street are stock. There are really no stock cars that I can think of under a few hundred grand that will beat a 400 rwhp FD.

Maybe you'll run into a 1,000 rwhp Supra someday... maybe. For random street encounters, even a 300 rwhp FD is pretty darn hard to beat. The average guy in a C5 vette just isn't -that- fast.

Now... maybe you have a lot of buddies with fast cars and you wanna beat them. Ok fair enough. Find out the HP they have, calculate their lbs/hp and make yours better.

Perhaps you want to run a 9.9 quarter mile. That takes some serious HP. Get the HP and run your 9.9.

I guess the point I'm trying to make is that if you want a very driveable nearly unbeatable FD for street cruising, shoot for 400-450 rwhp on pump gas. I promise you that you will have almost 0 chance of losing a race.

If you have a specific target in mind (like a 9.9 quarter, or your buddy with the XXX HP vette), build to that target and beat it.

 

my GT42R is laggy compared to my old twin turbo 3000GT (which spooled instantly) but is by no means unbearable. I make 16psi by 4300~rpm, hell i have 5psi the instant i hit the gas, even as low as 2200rpm~

 

sage advice here man.... remember this, most "encounters" on the street are stoplight to stoplight, or perhaps the quick blast on a freeway. In these area's 400 RWHP with a good solid HP/TQ curve under max boost is going to be the killer every time.

at 60-1/to4s/GT35r is quick off the line, with a decent topend and will totally whoop a$$ on 95% of the cars you will ever encounter.

yeah joe with the 600 hp stump pulling big block/minitubs and DOT slicks will spank you, but he will never enter a corner with you.

yeah old boy with the lotus Elise is going to give you hell in the corners, but come the first straight away and stand the F**K by....

you get the idea

dollar for dollar a 13b with one of the above is a good solid all around car, that with decent rubber will embarrass 100% of the cars on the road in one fashion or another, be it straight line, corners or cost.

Kenn

 

Stay away from SR motorsports.

 

gr63 from gotham. it always "makes the numbers" on the dyno, unlike most other turbo kits out there.

JOhn

 

Some great info on SR Motorsports here:

https://www.rx7club.com/questions-about-members-102/thinking-about-ordering-sr-motorsports-shane-racing-ray-lochhead-read-1st-628636/

 

If you want the 411 on turbos and what they are going to make then call me. I have dynoed and installed every kit on the market. Most of these guys are just going to recommend whats on their car because thats all they know.

 

Let us know what you recommend...I'm curious.
John

 

Like others have said it all depends on your goals. Streetability, HP and cost are the main factors when choosing a turbo.

Good streetable turbos that will produce between 400-500HP are T04R, T04Z, GT35R, 60-1, GR63, 500R etc.. All of those turbos will give you similar numbers give or take a few HP. Main difference between them is the cost.

 

Why the cost difference, everything in this world you get what you pay for, are some of these kits just charging for the name.

 

I suppose ultimately I would be willing to sacrifice some low end boost to have more efficiency up top, i am more of a highway blaster.

 

I once bought an FD with a 62-1 which maxed out made 440 whp (dyno jet numbers). I wanted a little bit more power, but not too much. I got a great deal on a bigger turbo (t-61) and I put that on and re-tuned it and turned up the boost. The new power level was around 500 whp (dyno jet) and was just enough to put a smack down on vipers and zo6's. The t-61 I had was more comparabe to a gt 40 than a gt35. A gt-40 should spool a little bit faster than my t-61, and will flow better.

Ithink I know exactly what kind of response/peformance you are looking for. You should consider something in the middle between the gt35 and the gt42, which would be the gt40.

Jason took the time to chime in on this thread and you should consider calling him. He can discuss this with you or sell you everything you need. I've been on this forum for 4 years now and I've gathered that he is very competent and honest.

 

I would say go with the right tuner first. You can have an inexperienced tuner and make dog crap for power and lazy spool with turbo that is capable of much better results. In the end, I would say along with everyone else, something like a GT35R or along those lines with decent sized turbine housing will net you what you are looking for. I enjoy a nice broad powerband under the curve. At 20 lbs, I was making around 500 whp full boost at around 4400 rpms and pulled like that till 8500, so about a 4100 rpms of full power and tq and this was on a 61.5 mm compressor wheel.

 

Well said Blitz.