Fazdarx_8's Top Mount Turbo Build
I could tell you the numbers or wait and post pictures and video's 
Pretty good runs, the motor was happy doing 10-11psi.
was really hoping to join the 300whp club but I didn't quite make it.
I am going to make some subtle changes in the cold pipes that might get me a little more.
Last edited by FazdaRX_8; Oct 28, 2012 at 03:25 PM.
I should clear that up, I did datalog all the runs, they the shop only had one 02 senser for the back exhaust so not very effective for a dual tip setup, and I have a leak right at before my second wo2
my cobb ap read 10.88
my lc-1 read about 11.2-11.6
while theres read that
they usually do diesal trucks then imports, I beleve they had 2 other stock rx-8 on the dyno, mine was the first and probably only FI rx-8. they where very suprised when I popped the hood lol
so for the exhuast leak the damn c-clamp must have warped when welding, so i need to sand the hell out of it to be flat again that will fix the leak
so 100% load at 3800 then @ 4300 124% load and 10.88 afr til redline
my cobb ap read 10.88
my lc-1 read about 11.2-11.6
while theres read that
they usually do diesal trucks then imports, I beleve they had 2 other stock rx-8 on the dyno, mine was the first and probably only FI rx-8. they where very suprised when I popped the hood lol
so for the exhuast leak the damn c-clamp must have warped when welding, so i need to sand the hell out of it to be flat again that will fix the leak
so 100% load at 3800 then @ 4300 124% load and 10.88 afr til redline
"So smooth!" lol How many times did you guys say that?
Tailpipe AFR gauges are only, at best, useful as a "back-up plan" to an aftermarket gauge in the midpipe somewhere.
Next best thing is the AP.
Even without an exhaust leak, the tailpipe will have a totally different "curve" than reality and will be .5 to 1.5 points leaner.
Even the slightest leak (and very, very few turbo setups that I have seen DON'T have a leak of some sort) will totally compromise the readings.
The best bet is to screw the shop's lambda sensor into the OE rear O2 sensor position (provided their system is good, up-to-date and properly calibrated).
That said, 12:1 or so is not a problem a few hundred RPM on either side of the torque peak, though it probably isn't optimal. "Technically", 12.3 is LBT, though I have yet to see a rotary make any more power that lean then it does at 11:1.
My guess, based on your other readings, is that it is still actually a bit rich.
Rather than AFR, I would have asked for boost pressure (or both since the Dynojet can put that on the other side of the AFR plot).
Your last log showed that you were into the 190% load range by the torque peak. It wouldn't be a good thing if you were only in the 120% range up there. What was your boost pressure at 6200 - 7200?
Getting rid of that divided housing on an undivided manifold would probably free up some exhaust flow better than most cold-side adjustments. Might help address that lag, too.
See you on the 26th.
Tailpipe AFR gauges are only, at best, useful as a "back-up plan" to an aftermarket gauge in the midpipe somewhere.
Next best thing is the AP.
Even without an exhaust leak, the tailpipe will have a totally different "curve" than reality and will be .5 to 1.5 points leaner.
Even the slightest leak (and very, very few turbo setups that I have seen DON'T have a leak of some sort) will totally compromise the readings.
The best bet is to screw the shop's lambda sensor into the OE rear O2 sensor position (provided their system is good, up-to-date and properly calibrated).
That said, 12:1 or so is not a problem a few hundred RPM on either side of the torque peak, though it probably isn't optimal. "Technically", 12.3 is LBT, though I have yet to see a rotary make any more power that lean then it does at 11:1.
My guess, based on your other readings, is that it is still actually a bit rich.
Rather than AFR, I would have asked for boost pressure (or both since the Dynojet can put that on the other side of the AFR plot).
Your last log showed that you were into the 190% load range by the torque peak. It wouldn't be a good thing if you were only in the 120% range up there. What was your boost pressure at 6200 - 7200?
See you on the 26th.
Last edited by MazdaManiac; Jul 19, 2011 at 05:27 PM.
Thanks Guys, I was really nervous, my friends where there, my welder was there, and it was my first dyno session. Next time I will ask about the boost logging
it seemed like I was getting 10-11psi most of the time, but in the higher rpms I admit-tingly was watching the tack so I knew when to let off. I am guessing the boost dropped off in the redline part of the graph though. perhaps the wastegate spring got hot? the blue one seems to keep climbing, even though the whole thing is lower.
290 @ 7200rpms
My load did climb to a peak of 192.47 @5876rpms then falls
I am looking into the deletion of the divided housing or at least filing it down.
For now I have the pipe and couples to make a quick cold side adjustment, it will be from the intercooler to the 3" throttle body pipe. I will be going from 2" to 2.5", I did some flow testing in Solidworks and doing this change will result in a consistent speed through the system and a lower peak speed, currently there is a peak of 350+mph, where 304mph is Mach speed this one changes the highest from a corner to inside the intercooler but over a lower MPH
I Updated the dyno with a Higher res scan
it seemed like I was getting 10-11psi most of the time, but in the higher rpms I admit-tingly was watching the tack so I knew when to let off. I am guessing the boost dropped off in the redline part of the graph though. perhaps the wastegate spring got hot? the blue one seems to keep climbing, even though the whole thing is lower.
290 @ 7200rpms
My load did climb to a peak of 192.47 @5876rpms then falls
I am looking into the deletion of the divided housing or at least filing it down.
For now I have the pipe and couples to make a quick cold side adjustment, it will be from the intercooler to the 3" throttle body pipe. I will be going from 2" to 2.5", I did some flow testing in Solidworks and doing this change will result in a consistent speed through the system and a lower peak speed, currently there is a peak of 350+mph, where 304mph is Mach speed this one changes the highest from a corner to inside the intercooler but over a lower MPH
I Updated the dyno with a Higher res scan
Last edited by FazdaRX_8; Oct 28, 2012 at 03:25 PM.
Original Turbo 'd Auto !!
Joined: Mar 2004
Posts: 2,136
Likes: 5
From: Surprise, Arizona
for V-band clamps you're suppose to have the tube from one side extend out past the flange and into the other one, it not only provides alignment but keeps the flow from having direct access to the mating joint. I didn't see this on any of your pics, but if they're there then ignore this.
So an upgrade is in order
I was thinking 4 uncapped yellows in sec/aux and stock yellows in Primary position
then a Divided .84 T4 turbine housing to replace the 1.00
the troublesome 3" v-band clamp is in the down-pipe, not the header....
I was thinking 4 uncapped yellows in sec/aux and stock yellows in Primary position
then a Divided .84 T4 turbine housing to replace the 1.00
the troublesome 3" v-band clamp is in the down-pipe, not the header....