MHP v2 ECU/TCU (Complete Driveline Tuning) GP for IS-F
01-29-09, 09:03 PM
#17
A couple of months ago we were begging for an ECU tune and now we have a group buy, thanks Andy for supporting the Lexus community.
As I said in the ECU/TCU tune thread, I can feel the power improvement on the upper RPM range (I'm the ECU/TCU tune tester for those who didn't read the other thread). When I ran against a stock IS-F we were dead even until we went up on the revs, then I started walking the stock IS-F consistently. My experience driving the tuned IS-F together with the dyno graphs show that Andy and MHP delivered what they promised.
On the TCU side I can feel the car upshifting quicker while in auto mode (at WOT), and downshifting as needed without too much effort, compared to stock when the car tries to stay on higher gears. On partial throttle the car is very smooth as it should. While in manual mode it's really hard to notice any difference, the IS-F already shifts fast, so I can't comment on it. What I can say is that shifting is firm and quick on any mode.
I haven't been able to drive to West Palm Beach again to get 1/4 mile times, but a couple of weeks ago I went to the local 1/8 mile track. I've been going to this track since I got the IS-F last year and my times are very consistent. My best stock time was 8.57@85.5MPH, not bad for this track. The last time that I went (when runing the v1 tune) all my runs were better than the stock time, being the best 8.41@87.6MPH. There is a good improvement in just 1/8 mile, so in 1/4 mile the car will have more room to take advantage of the higher rpm gains, and I can see a 0.4s improvement without a problem.
JUAN
As I said in the ECU/TCU tune thread, I can feel the power improvement on the upper RPM range (I'm the ECU/TCU tune tester for those who didn't read the other thread). When I ran against a stock IS-F we were dead even until we went up on the revs, then I started walking the stock IS-F consistently. My experience driving the tuned IS-F together with the dyno graphs show that Andy and MHP delivered what they promised.
On the TCU side I can feel the car upshifting quicker while in auto mode (at WOT), and downshifting as needed without too much effort, compared to stock when the car tries to stay on higher gears. On partial throttle the car is very smooth as it should. While in manual mode it's really hard to notice any difference, the IS-F already shifts fast, so I can't comment on it. What I can say is that shifting is firm and quick on any mode.
I haven't been able to drive to West Palm Beach again to get 1/4 mile times, but a couple of weeks ago I went to the local 1/8 mile track. I've been going to this track since I got the IS-F last year and my times are very consistent. My best stock time was 8.57@85.5MPH, not bad for this track. The last time that I went (when runing the v1 tune) all my runs were better than the stock time, being the best 8.41@87.6MPH. There is a good improvement in just 1/8 mile, so in 1/4 mile the car will have more room to take advantage of the higher rpm gains, and I can see a 0.4s improvement without a problem.
JUAN
01-29-09, 10:26 PM
#18
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Those are to the wheels 23rwhp/20rwtq SAE CF, smoothing set at 5, in 6th gear on straight 93 with charcoal filter in place.
At 17.5% DT loss (what we see with most modern automatics) that computes to 28hp/24lb/ft at the flywheel.
At 17.5% DT loss (what we see with most modern automatics) that computes to 28hp/24lb/ft at the flywheel.
01-30-09, 11:09 AM
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That would be our best guess, peak gains around 15rwhp. With gains across the curve in both HP/TQ. Unfortunatley what can't be quantitatively described is the far superior part and WOT drivability, sharpened throttle response, quicker/faster up and downshifts, and the elimination of tq management. Our tuning actually makes your car feel like a different vehicle. On certain makes the raised shift points will eliminate a shift in the 1/4 mile, which is huge for ET.
Thanks
Thanks
01-30-09, 11:10 AM
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These are things that Juan can corroborate I'm sure.
Thanks
02-04-09, 07:53 AM
#28
Speaking of... will you be able to make the TCU act like the IS-F in that it actually shifts and holds gears, or will "sport" mode still just be a top gear limiter?
Happy to volunteer if you need a mechanically stock IS350 test mule... there's a number of local dynos and an 1/8th mile track fairly close (and a 1/4 mile track a bit less close).
Last edited by Kurtz; 02-04-09 at 06:51 PM.
