Wondering what you guys think. I've had a .96 on my t70 for a while now and up until reasantly I've wanted to keep the .96 for what probably will be some great spool up on a hbp however I was thinking that a) it may be a tad small for over all hp as well as cause higher egt's. I've just reasantly come across a 1.32 that I could by for pretty cheap and was wondering what you guys think of the 1.32 and how well do you guys think it would spool. The more I continue to build my car and the more I go to the 1/4 mile track the more I'm wanting this for a drag type setup. I would like the streetabilty of the .96 but I have a feeling I'm right on the cusp(sp) of making that transition from really stupid fast street car to full on drag car. If ya'll have any input on this it would be greatly appreciated. Thanks.

 

Im happy with my 96 mm makes 450+ and drives good on the street. First run this year was 10.84 et. The engine runs cool 184 highest reading so far. But i dont try to top end the car so dont know the effect at speeds above 127 mph!

 

10.84 is not bad at all. What size turbo do you have? Do you have a half bridge with that .96 or is it street ported? I'm just looking for the best 1/4 mile track combo.

 

Hi hondahater, How’s things?
In my opinion you should stick with the .96. I don’t think there will be any real power gain going to the larger 1.32.
I’m still running my .84 on full bridge @ 1.6bar.
The small housing seems to do the business when used with large wastegates.
The biggest advantage i see with larger housings is that it puts a lot less work load on the wastegate.

I think if you want to make more power by reducing back pressure and heat build up its best to go for larger turbine wheel rather than a laggy housing.
I’m being convinced more every day that a larger frame turbo ie gt42 gt45 can have similar response properties to t4 running large housing option.

To put things into perspective though as far as how much hp small housing can flow… I have a drift customer running MP GT37 which is similar to 60-1 compressor using a tiny .7ar turbine housing @ 415whp with turbine smaller than p trim,

Cheers

 

Hey man, doing good just getting more into this drag thing and have started taking a differant direction with my car thus wondering how to get the best/most power from my t70. Thanks for the explination on why to stay with the .96. I've always thought it was the turbine size that makes more power but after listening to you it sounds like the bigger the wheel is the more power you will get. Thats some incredible power for a gt37 with a .7ar hotside. It really does put things into perspective. Thanks again.

 

587rwhp on 18psi on pump fuel on housing bigger than 1.32a/r

Power band perfectly suited to stock gearbox ratio's, instant power to light tires in any gear at any speed... I rest my case

Small housings KILL these engines.

Cosmo half bridge rev range from 5k to 8.5k (full boost)

 

You know my vote. There is still lag time between w/g opening/closing and pre-turbine back pressure going through the roof with the small housing. Not the case with a bigger turbine housing. If that was the way to go then diesels wouldn't be running such large housings...

Sure you're going to see an increase in " lag " if you puffing through puny 3" restricted exhaust system..

 

oh crap! there's never a definative answer is there? So lets say I decide to experiment on the dyno with them. Haveing the big housing and a smaller 3" exhaust would be bad? If I did go with the 1.32 would I have to up my exhaust to 4"?

edit: note, my exhaust system is a 3" straight through single, nothing but a borla midpipe.

 

In my experience exhaust size has the biggest impact on boost threshold. Turbine a/r is minimal when you have a free flowing exhaust system 3.5" straight through muffleres.. Obviously its going to be different for each engine, porting/ sealing compression etc. Best thing to do is just instrument the car and play around, turbine housings are not that expensive...

 

no I found one for cheap so I don't mind trying it at all. I just have to take the car to get tuned so I guess I'll take the turbine with me at that time. As far as compression goes I should make perfect compression being that the housings and everying internally is new mazda parts.

 

Mate

We do 578rwhp on a dynodynamics machine thats 720bhp @ engine on 18 psi on a 3.5" exhaust one SMB rear muffler and one SMB resonator, the car is very tollerable on noise (dare I say quiet compared to some of any power comaparable to us). It runs over 600rwhp on road at boost we cant maintain on dyno.

Look up SMB exhausts (Australian company) on the net and speak to Grant, tell him I sent you proven mufflers in the hardest environments.

 

thanks for the info man! I'll look those up. Only reason I'm saying crap on an exhaust system is because I just bought my 3", lol. It's got 0 miles on it, oh well I guess thats the name of the game. Was talking to a Puerto Rican guy that has a 7 second rotary dragster and he was saying how he is building his wife a car just out of all the parts he had taken off his car to replace with upgrades. He basically said do it once do it right. He said he wishes he would have done that from the beginning because it would have saved him lots of money!

 

i have a 1.10 Q-trim on my 70mm... 3.5" exhaust, large street port w/ bridge on the secondaries, blow-thru carb setup, etc....

i pretty much cruise in boost, give it the slightest bit of throttle and it's instantly at 5psi... leaving stop lights i'm atleast around 5 or 6psi 1/4 throttle. the car gets up and goes on the street like it's nothing. when it's time to go wide open there's really no wait. YES there is lag, but with the bridge it makes it feel like my buddies ****** bnr hybrid!!!! haahahahha
the .96 will be fun, but the 1.32 will OWN but please step up on the exhaust.. it really does help

i'm actually switching to a borg warner S475 T6 turbo in a couple months.. this T70 feels too small hahahaha

 

lol thanks for the responce. What do you think will be the differance in having the .96 and the 1.32. I'm going to make a few passes with this t70 and if I feel my car needs more I'll go ahead and get the masterpower gt45 or I can find a garrett gt45 for 750. Anyways if people can tell me the differances I'll see between the two turbines it would be great! Thanks.

 

they're all gunna laugh at you...





ps. you'll never finish your car at this rate.

 

who is all going to laugh at me? lol, I knew you where going to show up in this thread I just want to make sure my car is capable of what I want instead of building, dismantling, and upgrading like I have been doing. I might as well do it right for a change, you know?

 

yeah you right.

I keep making changes as well...seems to be more cf showing up at my house all the time


change one thing and I have to change three other things to accomodate...it all started with the GT3574 that I'm very excited to see what it can do. Our first race will be to see who can get the car started

 

hahahaha, no joke man. I know what you mean by having to change 3 things if you change one and that has bit me on my *** so many times with this project. My mind is in like 10 differant places and I can't seem to get my head straight with it. I actually have a tad bit of money as a budget so I don't mind doing the right things to it but on this forum you get like 10 differant "this is the right way" answers that sometimes I act before I am completely sure of what to get. Of course there is that and then there is the real reason. I'm caught inbetween wether or not I want to build this car for straight drag or if I want to road race as well. The ford 9" and the 5gallon fuel cell is constantly on standby for this reason right here. Anyways before I go way off it's nice to see you're blingin' your car out Man I still can't wait to see a nice fd. It's been a while since I've seen an fd in your kind of condition. See you at the track...... baybe

 

Im not going to say the 96 hot side makes big hp, but with the turbonetics 62-1 and 96 housing i went 10.84 at 126. I have ac power steering and cruse. The car weighs in at 2800 lbs. I was running 19 lbs with 98 octane at 10.5 afr. The car also cut a 153 60 ft time. Its also a touring with leather. The car runs 180 degrees idleing and runnes cooler racing. Im proud of the way the car runs and idles and still dependable. There are people that know alot more about rotarys than i do but these are the facts on my car. Good luck what ever you do!

 

I am running a 75mm turbo with a T6 1.32 a/r on a stock ported motor. We stopped tuning at 445 HP but i plan on pushing it much further. For what it is the boost response time is not bad at all! There are a few vids of it in my sig. I think the designs of turbos have come a long way lately (Borg Warner, Garrett GT). What use to be considered too big seems to work fine now.

 

Hey your setup is proven, if your making 10.84 in the 1/4 then you are obviously doing something right. You have the stock rear end? You must be a damn good driver. This is what I don't understand about drag racing rx7's. I was just looking at this post https://www.rx7club.com/racing-kills-lounge-10/fd-vs-fd-zinx-vs-radkins-%2Avids%2A-%2Apics%2A-more-648037/ and thought it was strange that these guys have to4r's 1/2 bridge at 20 psi and are only making 11's. One is on street tires so maybe thats what it is but it's not the only time I've seen people with big turbos and a good size port make 11's and 12's witch is just slow for the amount of money that I'm sure is tied up in thier project. You have a smaller turbo and your making faster times. Thats interesting. Anyways I've always thought that the hotsides determine a few things.

1. more flow witch means it doesn't choke your exhuast up witch means that you can get boost past what the .96 can.

2. Since there is more flow it alows for cooler egt's

3. alows for higher hp due to free flowing exhaust witch means more in, more out so your hp will ultimatley be higher.

Now of course one thing I didn't think of until just now is maybe the .96 is better for lower boost and once you start getting over say 20-25psi then a larger hotside is ideal? I'm going to be shooting for pretty high boost as a) I will have alky injection and b) I just found out that the track I'm going to has 112 race gas so I'll be most likely using this when I race. Any one else have opinions?

edit: just won the 1.32 for 49 bucks shipped. I guess we'll see how it goes.

 

power is based on trap speed not times. i have seen a few go down the track, get a 12.5 at 126 mph. thats just because they didnt get any traction off the start.

as for the 1.32 i am thinking about running it also. cant wait to see your results...

 

I'll probably use both the .96 and the 1.32 when dyno tuning to see the differance. I do think probably the .96 will do great on the track because since it's small the boost will be there quicly and also because it's ceramic coated as well as I have a blanket to put on it so that should just help spool up that much more.