Single Turbo RX-7's Questions about all aspects of single turbo setups.

GT4202 29psi freeway test

Thread Tools
 
Search this Thread
 
Old Jun 9, 2013 | 11:46 AM
  #1  
kevinbtz's Avatar
Thread Starter
Shell 93
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jun 2004
Posts: 1,019
Likes: 20
From: Little Rock, Arkansas
AR GT4202 29psi freeway test

Just finished taking a customers car from a previous tune of 21psi and taking it up to 29psi on pump gas (Shell 93). The car is a blast, in the 70-135mph vid it breaks traction from 83 to 100mph then shifts in to 4th at 106. The car is running a AEM and gets in between 25-28 mpg when not totally raging on it. The current tune on the car has about 20hrs in to making very driver friendly and smooth. It also has a multi stage water injection controlled by the AEM. The Vid is in HD so play it on a fast connection/computer or it will glitch.


Last edited by kevinbtz; Jun 9, 2013 at 12:04 PM.
Reply
Old Jun 9, 2013 | 12:04 PM
  #2  
rx72c's Avatar
Rotary Freak
Tenured Member: 20 Years
Top Answer: 1
iTrader: (8)
 
Joined: Jun 2003
Posts: 2,878
Likes: 195
From: Australia
Sounds beautiful Congrats on the Pump fuel WI tune.
Reply
Old Jun 9, 2013 | 12:19 PM
  #3  
kevinbtz's Avatar
Thread Starter
Shell 93
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jun 2004
Posts: 1,019
Likes: 20
From: Little Rock, Arkansas
Thanks, especially from you. Ever since I did my T88 at 28psi a few years back and raced it every weekend with out a hiccup, its the only way I will tune on high boost pump gas.
Reply
Old Jun 9, 2013 | 03:47 PM
  #4  
rx72c's Avatar
Rotary Freak
Tenured Member: 20 Years
Top Answer: 1
iTrader: (8)
 
Joined: Jun 2003
Posts: 2,878
Likes: 195
From: Australia
once you get it right you unlock the world of potential for reliable High HP rotaries.
Reply
Old Jun 9, 2013 | 04:50 PM
  #5  
kevinbtz's Avatar
Thread Starter
Shell 93
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jun 2004
Posts: 1,019
Likes: 20
From: Little Rock, Arkansas
No doubt, with the proper recipe these motors can make ridiculous power on pump gas. My favorite thing to do is pick on crotch rockets who are then in disbelief when you pull away from there liter bikes.
Reply
Old Jun 10, 2013 | 03:28 AM
  #6  
Jobro's Avatar
SAE Junkie
Tenured Member: 20 Years
iTrader: (2)
 
Joined: Mar 2005
Posts: 1,287
Likes: 12
From: OZ/AU
Wow thats awesome! I would love to see some in cars footage. I would also love to use one of those turbos on either of my rotaries but I'm not prepared to put up with the downsides
Reply
Old Jun 10, 2013 | 03:52 AM
  #7  
rx72c's Avatar
Rotary Freak
Tenured Member: 20 Years
Top Answer: 1
iTrader: (8)
 
Joined: Jun 2003
Posts: 2,878
Likes: 195
From: Australia
your a bloody chicken. get over your crap turbos and get something serious for once.
Reply
Old Jun 10, 2013 | 07:07 AM
  #8  
Rotor Nut.
Tenured Member 20 Years
iTrader: (34)
 
Joined: Feb 2002
Posts: 2,163
Likes: 2
From: RI
You guys need to pick up some vboxes so we can all compare highway speeds. 60-130 etc..
Reply
Old Jun 10, 2013 | 02:43 PM
  #9  
boosted414's Avatar
547hp at the flywheel
Tenured Member 10 Years
iTrader: (30)
 
Joined: Oct 2008
Posts: 1,223
Likes: 0
From: Chicago
Ya I agree. No turning back once you add some water injection. I'm still down at 22 psi and pull in bikes. They have no idea how to respond.
Reply
Old Jun 10, 2013 | 06:45 PM
  #10  
dabigesii's Avatar
Back to basics
Tenured Member: 20 Years
Liked
iTrader: (4)
 
Joined: Mar 2004
Posts: 855
Likes: 12
From: Crescent City
Very badass
Reply
Old Jun 10, 2013 | 06:51 PM
  #11  
jetlude's Avatar
BadAss DoItYourselfer
Tenured Member: 15 Years
iTrader: (9)
 
Joined: Jun 2008
Posts: 870
Likes: 4
From: Paradise
Originally Posted by kevinbtz
Just finished taking a customers car from a previous tune of 21psi and taking it up to 29psi on pump gas (Shell 93). The car is a blast, in the 70-135mph vid it breaks traction from 83 to 100mph then shifts in to 4th at 106. The car is running a AEM and gets in between 25-28 mpg when not totally raging on it. The current tune on the car has about 20hrs in to making very driver friendly and smooth. It also has a multi stage water injection controlled by the AEM. The Vid is in HD so play it on a fast connection/computer or it will glitch.

1994 RX7 Highway Rolls Stupid Fast! ! ! - YouTube
Great video, however, I am very curious to know how the FD feels as it looses traction at the rear at 80 - 100mph. Does it tend to fishtail like it does in second, or is it more stable . I know there are several variables that can influence this such as tire with and suspension setup. I am assuming that you guys are running stock suspension.

I am presently at a little over 500hp but cant say that I have fully experienced these conditions since I have far surpassed the ratings of my clutch.
Reply
Old Jun 10, 2013 | 08:17 PM
  #12  
864angel112's Avatar
Senior Member
Tenured Member 10 Years
iTrader: (7)
 
Joined: Jul 2008
Posts: 540
Likes: 0
From: Greer,Sc
Nice going man love them pulls
Reply
Old Jun 10, 2013 | 10:24 PM
  #13  
sk8world's Avatar
Chasing numbers
Tenured Member 20 Years
iTrader: (5)
 
Joined: Apr 2001
Posts: 5,097
Likes: 4
From: Alabama
Originally Posted by jetlude
Great video, however, I am very curious to know how the FD feels as it looses traction at the rear at 80 - 100mph. Does it tend to fishtail like it does in second, or is it more stable . I know there are several variables that can influence this such as tire with and suspension setup. I am assuming that you guys are running stock suspension.

I am presently at a little over 500hp but cant say that I have fully experienced these conditions since I have far surpassed the ratings of my clutch.

I would guess it would more depend on how much power and what tires like you mentioned above. Mine is unstable when it hits at 36psi on street tires in 4th gear. Will only try it again on drag tires.

It's crazy to see cars pushing 93 octane so far.. Congrats on the results.
Reply
Old Jun 10, 2013 | 10:36 PM
  #14  
kevinbtz's Avatar
Thread Starter
Shell 93
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jun 2004
Posts: 1,019
Likes: 20
From: Little Rock, Arkansas
Originally Posted by jetlude
Great video, however, I am very curious to know how the FD feels as it looses traction at the rear at 80 - 100mph. Does it tend to fishtail like it does in second, or is it more stable . I know there are several variables that can influence this such as tire with and suspension setup. I am assuming that you guys are running stock suspension.

I am presently at a little over 500hp but cant say that I have fully experienced these conditions since I have far surpassed the ratings of my clutch.
The car has the usual suspension mods with a locking diff, I have also tweaked the alignment (no alignment machine just with some simple tools I have made) to make the car very controllable while spinning the tires. It does take some steering correction while it looses traction but very predictable, nothing like the REW T66 1stgen that I built almost 10 years ago which would snap over steer and would not stop spinning till 4th gear. Learning how to control that 1st gen was the best "driving school" for high hp street driving. One thing you have to be prepared for is when the road surface has a joint or changes from concrete to asphalt and vice versa, I have spun tires going over 120 from those conditions.
Reply
Old Jun 10, 2013 | 10:39 PM
  #15  
kevinbtz's Avatar
Thread Starter
Shell 93
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jun 2004
Posts: 1,019
Likes: 20
From: Little Rock, Arkansas
Also, thank you for the complements guys.
Reply
Old Jun 11, 2013 | 10:31 AM
  #16  
RogueFab's Avatar
Full Member
iTrader: (2)
 
Joined: Feb 2013
Posts: 158
Likes: 0
From: Pacific Northwest
Wow. Wouldn't mind seeing an in-car either. Great sound. Congrats on the tune. Any pics of the car? Love them in white.
Reply
Old Jun 11, 2013 | 03:31 PM
  #17  
ArmenMAxx's Avatar
Rotary Freak
Tenured Member: 20 Years
Liked
iTrader: (21)
 
Joined: Jul 2005
Posts: 1,629
Likes: 55
From: Los Angeles
I never would of thought that running just aux injection would be enough to boost 25+psi. People always told me aux injection is only good till 21-23psi and from there you would need race gas.

You obviously have success with 29psi. Car is running solid!
Reply
Old Jun 11, 2013 | 09:40 PM
  #18  
rx72c's Avatar
Rotary Freak
Tenured Member: 20 Years
Top Answer: 1
iTrader: (8)
 
Joined: Jun 2003
Posts: 2,878
Likes: 195
From: Australia
Originally Posted by ArmenMAxx
I never would of thought that running just aux injection would be enough to boost 25+psi. People always told me aux injection is only good till 21-23psi and from there you would need race gas.

You obviously have success with 29psi. Car is running solid!
I did this years ago now.
Pump fuel Water injection 34psi
703rwhp
Reply
Old Jun 12, 2013 | 12:30 PM
  #19  
TheAsset's Avatar
Mr.Epic
Tenured Member 10 Years
iTrader: (11)
 
Joined: Jul 2009
Posts: 683
Likes: 2
From: Missouri
How much water are you guys putting in at those boost levels?
Reply
Old Jun 12, 2013 | 01:37 PM
  #20  
ArmenMAxx's Avatar
Rotary Freak
Tenured Member: 20 Years
Liked
iTrader: (21)
 
Joined: Jul 2005
Posts: 1,629
Likes: 55
From: Los Angeles
Originally Posted by rx72c
I did this years ago now.
Pump fuel Water injection 34psi
703rwhp
Thats crazy

was it pre-turbo injection? and as ^ mentioned, how much water were you using?
Reply
Old Jun 12, 2013 | 03:19 PM
  #21  
Narfle's Avatar
Rx7 Wagon
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (16)
 
Joined: Nov 2002
Posts: 6,978
Likes: 888
From: California
Originally Posted by ArmenMAxx
I never would of thought that running just aux injection would be enough to boost 25+psi. People always told me aux injection is only good till 21-23psi and from there you would need race gas.

You obviously have success with 29psi. Car is running solid!
It's not generally considered safe. 23ish psi is the supposed limit for WI. After than you're on to meth and/or race fuel.
Reply
Old Jun 12, 2013 | 07:18 PM
  #22  
jacobcartmill's Avatar
just dont care.
Tenured Member 20 Years
iTrader: (6)
 
Joined: Jul 2002
Posts: 9,387
Likes: 4
From: Nashville, TN
i have a hard time believing that thing gets anywhere near 28mpg cruising. what kind of advance and afr are you running at cruise? and what MPH?
Reply
Old Jun 12, 2013 | 10:21 PM
  #23  
JZG's Avatar
JZG
Full Member
 
Joined: Jun 2009
Posts: 152
Likes: 14
From: 3116
Originally Posted by Barban
It's not generally considered safe. 23ish psi is the supposed limit for WI. After than you're on to meth and/or race fuel.
Not true.

Like rx72c I have a high boost pre turbo WI setup

93 pump petrol
38psi
740rwhp
BW475
TII engine/intake

On 40psi the car has trapped 156mph on the 1/4 mile.

I don't think there would be much more hp to be made on E85 with this setup. I know which is easier to run!


Great vid by the OP!
Reply
Old Jun 13, 2013 | 02:08 PM
  #24  
dabigesii's Avatar
Back to basics
Tenured Member: 20 Years
Liked
iTrader: (4)
 
Joined: Mar 2004
Posts: 855
Likes: 12
From: Crescent City
Originally Posted by JZG
Not true.

Like rx72c I have a high boost pre turbo WI setup

93 pump petrol
38psi
740rwhp
BW475
TII engine/intake

On 40psi the car has trapped 156mph on the 1/4 mile.

I don't think there would be much more hp to be made on E85 with this setup. I know which is easier to run!


Great vid by the OP!
Absolutely bonkers!!! O_O I'm stuck at 25psi with my preturbo water/method injection due to my twin plate slipping pretty bad (had it on for about 5+ years of hard abuse) whenever I feel like forking over the cash for replacement parts, I'm shooting to max out my gm map sensor on just 93+ water/meth (32ish psi I'm assuming). I will say that with my current setup and before the clutch really started dying I was spinning my 295 r888s at over 70mph before they would hook...now they only spin until about 60mph.
Reply
Old Jun 13, 2013 | 03:51 PM
  #25  
kevinbtz's Avatar
Thread Starter
Shell 93
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jun 2004
Posts: 1,019
Likes: 20
From: Little Rock, Arkansas
Originally Posted by jacobcartmill
i have a hard time believing that thing gets anywhere near 28mpg cruising. what kind of advance and afr are you running at cruise? and what MPH?
Yep, a lot of people do. The advance and afr all depends on port size, turbo size, compression ratio, and so on. On this car I run a solid 14.9-15.2 during the constant cruse, leaner under the cruse load to 15.7, and richer 13.7 during vacuum acceleration. One thing people also forget about is the TPS Accel modifier tables and how drastically they can change your fuel mileage even when you think you have a steady throttle but your voltage filter is not right. As for my timing, each engine/set up is different. I just tuned a rx8 motor in a 79 1st gen rx7 with a Electromotive TEC GT that got 35 mpg on a round trip. I have been tuning pump gas rotarys for almost ten years, and one thing I have always concentrated on is the reliability, driveability, and the fuel economy of the tune.


Also to the other question, I am running distilled water only in the pre turbo and pre TB locations.
Reply



All times are GMT -5. The time now is 12:18 PM.