I initially wanted a 500R , everyone cant stop talking about the response, boost coming on so low and what not. Great turbo but I think I want a little more up top.I don't think its right for me, I will agree for the right person a 500R is great for what it is, but hey, why not downshift. With the stock twins running as good as I could get them setup I didnt really have any big power until the mid 4000 rpm range, and it didnt bother me because when I was having fun I was never below that. Anyway I am trying to decide what size I should go with. I only have a street ported motor and am concerned that the larger 42R's will be too much for me without a bridgeport, I am going with the 4inch exhaust kit from A-Spec, those guys do amazing work, and am wanting someone to shed some light. What size should i go with and where will my response be. Also I am going with the Tial v-band setup so I may be limited with certain sizes but share your experience anyway, thanks. AAlso what is a good power range to shoot for with my setup?

PFC
Cj motorsport fuel system dual Bosch 044's
greddy 3 row 32r hg
crane ignition
xcessive lim
pump gas 93
cooling mist water injection, no meth (yet)
ceramic coating and turbo blanket

 

what's your target power range? You may be better off with a GT40R or the slightly smaller T04Z, which are both good for 500+rwhp

 

Just a bit of warning... 4" exhausts are kinda loud.

 

The Tial housings are nice, but with the exhaust pulses of a rotary the twin scroll setups seem to work better.

 

I have run the 40r and the 4094r (= to 4294). You need to decide what you power goals are and what you are going to use this for. roadrace, drag race, street car, dyno queen.
If its a drag car, then its never enough, go big!!!

 

I guess what I am after is a highway monster, that being said I still want some power below 5000 rpm, but I don't think the lag issuse that everyone complains about will be as big of an issue for me. Some of the guys I cruise around with have Ferrari's and boosted vettes, also some crotch rockets. My power goals are completely dependent on what will be safe. I know the bigger turbos flow alot more air at a given psi, and that one can't tune solely based on boost pressure but from what I understand the bigger turbos will be more efficient and have slightly cooler charge temps. I am going to be running the coolmist water injection, so I hope that helps the saftey factor a bit, may even allow me to turn the boost up a little higher then without it. I would love to have 600 whp, I just don't know if I can pull that off without a bridge port. I also havent driven a 600 whp FD so, its kind of ignorant of me to pick that number out of a hat, but its sort of based on what power to weight ratio I am after. I obviously would love to have a crazy fat power curve but it seems with the 2 rotor engine you have to sacrifice response for peak power. Am I crazy, do these power levels seem crazy for the street, it would seem to me alot of guys on the forums have street cars with big power. What is achievable for me with what sacrifice in response??

 

What kind of gas can you get in your area? (octane)

 

more like you cant hear yourself think! plus the bridge = youll be death within the first week of driving it!

 

My only options for fuel are 91 octane from shell, or esso, and also 94 octane with 10% ethanol from Husky which i have heard is not ideal. I was also gonna contemplate Torco race fuel concentrate, its expensive but it works. A friend of mine runs 16 psi with quite advanced timing on the stock twins with no issues, he tested it with a knock sensor while tuning at a dyno a couple summers. I am also running water injection as stated before.

 

As far as the cooling system goes I will use a greddy 3 row and a koyo rad.

 

What about oil cooling

thewird

 

Oops!

 

I decided on the dual oil cooler kit from fd newbie, mocal cores. Still no infor from you guys on what to expect from the gt42r without the bridgeport.

 

I think if you arent doing a brigeport the 42R is too big. You wont be using the full potential of the turbo, and with the added lag of a single entry Tial housing, you might not enjoy driving as much. I dont know exact power figures, so I cant help there.

 

Wrong! I'm running a 42r with very conservative streetport... No complaints yet! If you run the T6 frame you'll be pretty laggy but you need to choose your battles...

 

Yeah, I suppose I wasnt thinking about a street port. What kind of power are you making?

 

do it.. You will be fine. If 600 is all you want do the smaller 4294 or even the 4094..... You will atleast have a turbo to support 600+.

 

I think you are getting confused what is a twin Scroll rear housing and a Divided housing. Twin scroll is when all the exhaust pulses get passed to one part of the turbine wheel at a certain point the flapper (be it eletronically controlled or mechanical) opens up to pass the exhaust pulses to all of the turbine wheel.
There is no option on getting a twin scroll rear housing on a GT42, only divided and V band Tial type.

Have you had experiance of the Tial Housing to comment on it?
I run a HKS T51 which is the same type of design rear housing as the Tial, its a fluted design is physically smaller when compared to a divided housing.

Due to the design it actaully spools up quicker, why do you think TIAL have recently designed this as an option to the old tranditional divided T4,T6 frames?

I have had experiance of both designs on my engine , and the V band Fluted rear housing design does spool quicker.

 

I should have been more specific, most people use the term "twin scroll" to mean divided housing, so thats just what I go with for simplicity(since twin scroll manifold is a proper term). Ive actually used a valve that makes the turbo act like a twin scroll turbo and its great.

You can get the GT42R with a T4 divided housing, Ive had quite a few of them. Both Garrett and Precision make them. Its the T6 housing that isnt divided. Yes, I have used the Tial housings. There might be negligible differences between spool on a Tial and standard open housing, but nothing big. Tial actually designed them for a gasket-less flange, less weight, and ease of use. I have also used the HKS T51 turbos, Ive had them go on a couple Supras. Before I became a dealer for Tial I spoke with one of the engineers about their turbine housing design and the effect it has on spool up. I was told there was almost no difference and thats what Ive experience.

 

Do you have the specs on your T51r? I always wanted to know the specs on the turbo, yet nobody could ever tell me any!

 

There are 2 actually, the KAI and the SPL. Same turbine, different compressor. Turbine is 82mm inducer, 71.4mm inducer.

KAI comp- 70.3mm inducer, 94mm exducer

SPL comp-76.5mm inducer, 102.2mm exducer

 

^ I know that. I guess I should have specified. Do you have any turbine specs?

 

I listed the turbine specs

 

So it is settled, a 42r with a streetport is deffinitly a good option, I am gonna go with the fluted hot side from Tial, even if it doesnt spool quicker, which i think it will, it is vband and way lighter. Anyone else want to chime in on your 42r streetport setup, and what size your turbo is, feel free, im still deciding on size.

 

Any thoughts on a Precision 6765 instead? You can make near 42R power and spool loads quicker.