Best turbo on a 1/2 bridge
 

Hi guys
i need your help i need to know what turbo you all would run on your cars if it hed a 1/2 bridge and you wanted about 500RWHP or more out of it.

Cheers
Erdin

I am selling my T70 turbo kit that I used on a half/full bridge car. Let me know if you are interested.

Do you have pics stevnoz? If so, send to dvsmode@hotmail.com along with a quote.

Check out this thread: https://www.rx7club.com/forum/showth...readid=209200. If you need anymore info just pm me or e-mail me at 94rx7@charter.net.

steve you have dyno charts for bp with T70? I just got a T66 Qtrim to put on half bp

I think the best advice I can give is shoot for any turbo that you think would work nicely on a side ported motor, and then go up atleast one size on the exhaust housing. I had a Garrett 67-1 (in between T66 and T70) w/P trim A/R 1.15 on my half bridge and it worked very nicely. Good for about 500rwhp at 15psi.

that t70 was nasty. i had a t78 on my streetport and it was nothing compared to steven's setup.

Iv been told that the GT42/45 is a good turbo to go for on a half bridge but i just wanted to know what every body els is using on there cars.

87GTR, what ar did you use? I have a .81 qtrim ready to go, a little small, but it's for road race, and autocross. LMK how it works, BP motor is next:D, Carl Byck

using a .96 q trim undev

http://bdc.cyberosity.com/pictures/TonyFarkas/T66/

The onther turbo is a S300 with 1.15 exh dev housing.
didnt spool much until 3rd gear then you better hang on!!!!

im sure the s300 would spool faster if I can get .83 or .91 housing

So my .81 undivided may be good for the street port in your and Brians opinion? I am putting the T66 on my supra for now(~800rwhp+795TQ), when I get a little cash, I will put a little smaller turbo on the Supra, and put the T66 on my FC. Are you using the modified OBX mani still? If you are, can you LMK final what you did to fit the T66. Thank you, Carl

I'm glad you guys are finally putting good size turbos on those 1/2 bridged motors ;)

Thats what I'm planning on doing

Carl, My turbo would be a good choice for a half bridge :)

What turbo are u using mate.

The Gt 42/45 is expensive at hell. Stick with a Garrett or something that is easily servicable, and cheaper.

I think the gt 42/45 is too large for half bp you going to need nos to spool it in 1st and 2nd

Jim, I am "just" street port. Next motor will be a full bridge, I am building it now for the future:D
Carl Byck

I don't know about that. The 42/45 is supposed to be pretty fucking mean. I think with the increased flow of a 1/2 bridge it would be good. A street port *may* have problems though.

Im using a GT42 for my motor...

It will have no problems spooling.
1.15 A/R Divided.

Here's a pic of the monster

https://www.rx7club.com/forum/attach...postid=1808392

NICE

Sorry, not true!:)

I had the same turbo as T51 Spl on my car and it would not spool really good in 1st gear until 6500 2nd gear was better and 3 was a lot better.

im just compairing the 42' wheel sizes the turbo I ran. and I just dont see you making lot of boost in 1st gear or 2nd.

42/45 can make 5 psi in neutral on a small half bridge.

So Tony, You never said if you are using the OBX or not?

so guys i dont know if iam asking this in the right way or not but exactly how much air will a 1/2 bridge motor flow so how would u know what the best size of turbo to use is, iam asking cus iv got a 1/2 bridge on my engine with a XS TO4S and was able to produce about 450 at the wheels but it is runing out of puff which i dident know it was going to do or i wouldent have purchased it in the ferst place and my mechanic never warned me that this could happen so this is why iv posted this thread up now.

T66 or bigger IMO

What there is no load on the engine I dont see you making 5 psi in neutral

some one has got to show me that.:eek: :eek:

I don't buy it, either, and I build this stuff for a living.

B

He probably forgot to add "while bouncing off the rev limiter" ;)

Sure there's a load.:D Gotta accelerate the flywheel, rotors and alternator, don't ya?:D I don't know what RPM, I wasn't there at the time.

It seems to perform very well on a stock port motor, but other car trouble has interfered with real testing:(

What psi is that at? My next goal is 450rwhp for my TII, and I was hoping to make it with the T04S. So I'm going to need at least a half bridge or what? I don't really want to lose the spool up by going with a T66 or T78 or the extra $$ for buying the turbo and manifold, not to mention to rebuild it when necessary.

I wouldent recomend a 1/2 bridge with the TO4S it will run out of Puff so you couldent relly get the best out of the bridge with this turbo you need somthing bigger to get the best out of the bridge.

I got a T51SPL and it rocks....just not on a stock motor. I wouldn't even try it on anything smaller than a Bridge.

So you guys think a T04S would be good on a large street port? What a/r?(.70, .84, or .96) I really want to get to 450 to the wheels in my TII without N20 and without a BP if possible.

I have a .60 front cover, and a .81 p trim. It hits like a V8, but runs out of steam up top (350ish). I'd go with the .96, and a .70 compressor. That's good for 400rwhp. To get to 450-500 I think you will need a bigger turbo. I am going to use a .81 Q trim T66, and I may go to 1.00 if the .81 dies up top, but I think it will be perfect. Carl

Well if I can get to 400+ at least to the wheels with a SP, then I will use a small shot of N20 if necessary.

Anyone have an idea of the difference in spool time b/t different a/r's on a T04S?

So let me see if iv got this right for a bridged car you need a large turbo, somthing like T88, T66, T51spl or the 42/45 but what would the car be like on the road with one of these turbos.

Out of control ;) but in a good way

Tuned an Fd with a large side port and a TO4S and made 467rwhp at 15psi of boost. The turbo is an AR .70 compressor with a P trim AR 1.00 exhaust side.


With the 67-1 w/ P trim AR 1.15 I made full boost 800rpms earlier with the bridge than with a big side(5500 to 6300).

That is a tremendous # from what I have seen for the TO4S. the best I've ever seen was around 430, and that was one guy(excellent tuner),all others are around 400 rwhp here. Any dynos available, or when was 15 psi reached?

So with 20psi on a TII with a good SP, you think 450rwhp is a fairly easy goal?

Thats alot of power, what was your set up and what ecu ware you using.

I'm trying to get the dyno sheet from the guy. This was actually 467 corrected rwps, since I'm in Japan. If you convert to HP it's still over 450 rwhp. All I know is what it pulled. Don't believe me, ask Dragon or Jspecracer7. We're talking a big side port, close to what Dragon runs. If I told you I made 450rwhp on a TO4R would you believe me? In my experience a TO4R and a TO4S make about the same power at 14-15psi on the same setups.

I put the engine, well the car together that did that run. He's running a power FC, 550 primarys, 1680 secondarys, dual trust fuel pumps, huge side and ex ports, HKS 55mm internal diamiter Manifold, HKS Racing wastgate, 80mm front pipe, 90mm mid pipe and muffler, 2 core greddy intercooler with 70mm pipe's, port matched lower intake manifold, OS twin plate clutch, cusco diff.. and it was tuned by Igy with the power fc datalogit and wide band o2...

You guys are good:D Not doubting you guys, I just like to learn as much as I can. I am looking for a reasonably priced Tubular manifold that will allow me to fit a T66 on my S4. Alternately I'd like to buy the HKS extension(for the cast manifold) that allows the T66 to clear the frame rail, and the LIM. Nobody stateside seems to be able to get even a part #. I have pics if needed, but it is a cast ~12* bend with a T4 flange on either end.
Carl Byck

I know exactly the manifold and adapter flange you are talking about, and I may know where one is.. Problem is I won't be able to get down in that area to check if it's still there until next week somtime. Send me a PM to remind me somtime this weekend and I'll try to check.

Isent a TO4R alot bigger then a TO4s iv been told it almost as big as a T78

It's bigger yes, but at lower boost levels like 1kgcm it flows about the same air as a to4s, It doesn't really offer any performance gain till you turn the wick up to about 1.3-4 or so and that is where you'll see it start to out perform the S...

sounds like the TO4R would be a good compromise to go for out of the T78, T88 and the Gt42/45, what sort of power can i expect at 23lbs of boost with a 1/2 bridge.

It all depends on tuning, I'd guess 550+ rwhp is attainable