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-   -   GT4202 29psi freeway test (https://www.rx7club.com/single-turbo-rx-7s-23/gt4202-29psi-freeway-test-1037645/)

kevinbtz 06-09-13 11:46 AM

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.


rx72c 06-09-13 12:04 PM

Sounds beautiful Congrats on the Pump fuel WI tune.

kevinbtz 06-09-13 12:19 PM

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.

rx72c 06-09-13 03:47 PM

once you get it right you unlock the world of potential for reliable High HP rotaries.

kevinbtz 06-09-13 04:50 PM

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.

Jobro 06-10-13 03:28 AM

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 :(

rx72c 06-10-13 03:52 AM

your a bloody chicken. get over your crap turbos and get something serious for once.

smg944 06-10-13 07:07 AM

You guys need to pick up some vboxes so we can all compare highway speeds. 60-130 etc..

boosted414 06-10-13 02:43 PM

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.

dabigesii 06-10-13 06:45 PM

Very badass

jetlude 06-10-13 06:51 PM


Originally Posted by kevinbtz (Post 11490622)
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.

864angel112 06-10-13 08:17 PM

Nice going man love them pulls

sk8world 06-10-13 10:24 PM


Originally Posted by jetlude (Post 11491914)
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.

kevinbtz 06-10-13 10:36 PM


Originally Posted by jetlude (Post 11491914)
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.

kevinbtz 06-10-13 10:39 PM

Also, thank you for the complements guys.

RogueFab 06-11-13 10:31 AM

Wow. Wouldn't mind seeing an in-car either. Great sound. Congrats on the tune. Any pics of the car? Love them in white.

ArmenMAxx 06-11-13 03:31 PM

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!

rx72c 06-11-13 09:40 PM


Originally Posted by ArmenMAxx (Post 11492700)
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

TheAsset 06-12-13 12:30 PM

How much water are you guys putting in at those boost levels?

ArmenMAxx 06-12-13 01:37 PM


Originally Posted by rx72c (Post 11493004)
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?

Narfle 06-12-13 03:19 PM


Originally Posted by ArmenMAxx (Post 11492700)
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.

jacobcartmill 06-12-13 07:18 PM

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?

JZG 06-12-13 10:21 PM


Originally Posted by Barban (Post 11493652)
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!

dabigesii 06-13-13 02:08 PM


Originally Posted by JZG (Post 11494038)
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.

kevinbtz 06-13-13 03:51 PM


Originally Posted by jacobcartmill (Post 11493884)
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.

drftinmx6 06-13-13 08:28 PM

He'll I've heard of people running 25-30 psi on just straight pump gas (93 ) on a carbed setup which I thought was absolute bonkers, apparently it's all in the tuning , ESP the timing map

AaronJ 06-13-13 09:24 PM


Originally Posted by kevinbtz (Post 11494744)

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

Out of curiosity what cc are these injectors?

djseven 06-14-13 08:31 PM

156 traps on 93 and water...... Vids please.

Originally Posted by JZG (Post 11494038)
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!


JZG 06-15-13 06:03 PM

No vid of 156mph pass that I know of but here's a slower one. Best ET to date 8.86@155mph.


estevan62274 06-15-13 06:17 PM

^thats awesome man! Sweet 323

rotormind 06-16-13 06:26 AM


Originally Posted by JZG (Post 11496578)
No vid of 156mph pass that I know of but here's a slower one. Best ET to date 8.86@155mph.

Green Brothers Racing 323 wagon 9.1@ 153 Dragmasters 2013 - YouTube

Lol this is probably my favorite rotary car of all times.

Howard Coleman 06-16-13 06:47 AM

do keep in mind the car is approx 2300 pounds... this is not to take anything away from the Green Brothers performance. i, too, think they have not only have they gone really fast and but they have shared a lot of the details on our board.

i was especially interested to learn about their tuning process.

if you are not familiar w them look for their threads/posts. good stuff.

howard

darkphantom 06-17-13 07:30 AM


Originally Posted by smg944 (Post 11491351)
You guys need to pick up some vboxes so we can all compare highway speeds. 60-130 etc..

agreed.. i would like to have a video from you from like a 40-130 while i post the same video to see the results..... I have one of a Zr1 from 40-130 that i was going to post up between his car and mine..

darkphantom 06-17-13 08:16 AM


Originally Posted by drftinmx6 (Post 11494976)
He'll I've heard of people running 25-30 psi on just straight pump gas (93 ) on a carbed setup which I thought was absolute bonkers, apparently it's all in the tuning , ESP the timing map

.


your asking for trouble right there

Narfle 06-17-13 11:29 AM

You and Rice are outliers, in terms of what you are willing to push on WI.
While impressive, your example is not representative of the general case for water injection.


Originally Posted by JZG (Post 11494038)
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!


KNONFS 06-17-13 01:44 PM


Originally Posted by Barban (Post 11497792)
You and Rice are outliers, in terms of what you are willing to push on WI.
While impressive, your example is not representative of the general case for water injection.

What do you mean? Are there others that have attempted to run pre turbo WI at "extreme" pressures on pump gas, without any success?

Not arguing what you are saying, but I am intrigued if others have attempted to follow the lead and have failed.

m4drx 06-17-13 03:31 PM

goes very well :)

TheAsset 06-17-13 03:39 PM

Has anyone answered how much water is being injected?

JZG 06-19-13 04:09 PM

About 1300 or 1400cc at 20psi from memory.
Yep, car is 2400lbs in street/race trim

TougeSpirit 06-20-13 12:59 AM


Originally Posted by JZG (Post 11499787)
About 1300 or 1400cc at 20psi from memory.
Yep, car is 2400lbs in street/race trim

more videos please, in car etc!

rofuz 06-20-13 02:46 AM

Takes off like a mf...

Bwarrrrrp 06-20-13 07:31 AM


Originally Posted by kevinbtz (Post 11494744)
Also to the other question, I am running distilled water only in the pre turbo and pre TB locations.

does a couple ppm of additives make much difference? How pure is the distilled water?

kevinbtz 06-20-13 10:51 AM


Originally Posted by Bwarrrrrp (Post 11500302)
does a couple ppm of additives make much difference? How pure is the distilled water?

Its only $1 a gallon and will not clog the nozzles as easy as drinking water.

Narfle 06-20-13 11:36 AM


Originally Posted by KNONFS (Post 11497918)
What do you mean? Are there others that have attempted to run pre turbo WI at "extreme" pressures on pump gas, without any success?

Not arguing what you are saying, but I am intrigued if others have attempted to follow the lead and have failed.

Plenty of people have tried to do what Rice and JBZ(and this particular car) are doing and failed, not because the theory is flawed but because the execution is difficult and the consequences are grave.
The general population tends to trend behind the bleeding edge. Moreover, most of the cars here are pure street cars. Most members don't have the time/money/expertise/tuning-ability that rice and others have.
Most people pushing anything higher than low to mid 20psi are going to be running meth and/or race fuel.

30-40psi on pump w/ straight water injection possible? Sure.
Suggested for your average consumer? Absolutely not.

Most people can't push that much boost on anything reliably. Period.
It takes a lot more than some water injection to run that much boost. That's the point I'm trying to convey.

silverfdturbo6port 06-20-13 12:21 PM

I agree. Peter and I have talked lots over the years and set up my car the way he recommended. I Ran 35psi last fall with about 1200cc's between pre turbo injection and a nozzle at the Tb elbow. Its very tedious when tuning and no room for error especially with the fd's weak spots in the rotors.
But spinning 5th gear easing into boost at 40mph is nothing to brag about ITS SCARY! But I just had to do it once.


Originally Posted by Barban (Post 11500480)
Plenty of people have tried to do what Rice and JBZ(and this particular car) are doing and failed, not because the theory is flawed but because the execution is difficult and the consequences are grave.
The general population tends to trend behind the bleeding edge. Moreover, most of the cars here are pure street cars. Most members don't have the time/money/expertise/tuning-ability that rice and others have.
Most people pushing anything higher than low to mid 20psi are going to be running meth and/or race fuel.

30-40psi on pump w/ straight water injection possible? Sure.
Suggested for your average consumer? Absolutely not.

Most people can't push that much boost on anything reliably. Period.
It takes a lot more than some water injection to run that much boost. That's the point I'm trying to convey.


drftinmx6 06-22-13 08:27 AM

^^ you did that on your precision turbo?

schaft 06-22-13 08:38 AM

Holy rocket ship

rx72c 07-08-13 04:59 PM

I do not run distilled water.

rx72c 07-08-13 05:01 PM


Originally Posted by Barban (Post 11500480)
Plenty of people have tried to do what Rice and JBZ(and this particular car) are doing and failed, not because the theory is flawed but because the execution is difficult and the consequences are grave.
The general population tends to trend behind the bleeding edge. Moreover, most of the cars here are pure street cars. Most members don't have the time/money/expertise/tuning-ability that rice and others have.
Most people pushing anything higher than low to mid 20psi are going to be running meth and/or race fuel.

30-40psi on pump w/ straight water injection possible? Sure.
Suggested for your average consumer? Absolutely not.

Most people can't push that much boost on anything reliably. Period.
It takes a lot more than some water injection to run that much boost. That's the point I'm trying to convey.

Like I said before. I did this many years ago now and have done it for many of customer's who enjoy HIGH HP rotaries that are more reliable than most. It isn't rocket science. Good ignition, lots of water and you are half way there.

unwritten-dinasty 07-10-13 11:43 AM


Originally Posted by rx72c (Post 11515105)
I do not run distilled water.

Tap water?


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