Shortened wastegate rod mod - 14.4% more acceleration.

[DEJON-Dave]

DEJON GXP Test with shortened wastegate rod mod - 14.4% more acceleration.

Saturday I performed this mod and tested it on my 07GXP with all our hardware mods. The results were GREAT. I ran the WG actuator lock nuts up to about 1 full thread left and hooked up the HP Scanner. I’ve done extensive testing before on a flat straight road near me. I always get in 3rd gear at about 2000-2300 rpm and floor it to redline. Then I turn and make a return pass and usually repeat for 4 passes and average the results. Then I note the frame and time at about 3500rpm (47mph) and 6000rpm (82mph). I divide the rpm(mph) by elapsed time to get a MPH/sec average acceleration.

Since I never tested my car with in pure stock condition, I need a baseline. So on 11/16 I met Alex Jones at Findlay, Ohio and scanned his stock GXP for 4 - 3rd gear runs. They averaged to 6.41mph/sec from 46-82mph.http://www.solsticeforum.com/forum/i...ies/smile2.gif


On 11/29 I tested my car with all my DEJON hardware mods, stock boost control and stock wastegate rod adjustment.
4 runs averaged to 6.69mph/sec (4.4% improvement)http://www.solsticeforum.com/forum/i...lies/wink2.gif


On 12/1 I modded the rod with no other changes and 4 runs averaged 7.05mph/sec (10.0% improvement)
I noted that the AFR on my AEM Wideband 02 was reading 16 at the 20.6psi boost spike at 3387rpm.http://www.solsticeforum.com/forum/i...ies/yesnod.gif


So I started increasing the fuel via HP scanner’s editor on the “Power Enrich” table and after several iterations I was able to get a 4 run average of 7.33mph/sec (14.4% improvement). This is the only ECU mod, no timing or cam angle changes etc. The ECU reduces TPS slightly from 3000 to 3900 rpm and 5000 to 6000 so I think I may be maxed out on torque control. But power is 14% above stock! http://www.twowheelforum.com/images/smilies/woohoo.gif


Following is the Power Enrich table (note 1.00 is 14.7AFR, multiply by the % below to get commanded AFR)
............. Stock....... DEJON#28
RPM ...80 90 100 ..... 80 90 100 (load)
1200... 1.00 1.00 .95 ...1.00 1.00 .95
1520... 1.00 1.00 .95 ...1.00 .98 .95
1760... 1.00 1.00 .95 ...1.00 .98 .95
2000... 1.00 1.00 .95 ...1.00 .97 .94
2520... 1.00 1.00 .95 ...1.00 .94 .86
3000... 1.00 1.00 .95 ....97 .91 .83
3520... 1.00 1.00 .95 ....97 .92 .85
4000... 1.00 1.00 .95 ....98 .94 .89
4520... 1.00 1.00 .93 ....98 .94 .89
5000... 1.00 1.00 .88 ....96 .93 .88
5320... 1.00 1.00 .87 ....96 .93 .87
6000... 1.00 1.00 .87 ...97 .93 .87
This enrichment should improve all cars currently running the stock tune with this WG rod mod regardless of other mods such as other Pipes, IC’s or exhausts. It’s a freebe from DEJON for anyone with access to HP tuners or other customer programmable software. Use it at your own risk but it will be safer than stock. http://www.solsticeforum.com/forum/i...ies/hurray.gif


Anyone with DEJON Intake or IC on their 07 can drive to my shop for a free software download. I don’t have the HP 08 license yet, but pm me. If you have HP software and want to see the scans, email me at sales@DEJONTOOL.com

[lil goat]

Wow thanks Dave that is some cool stuff. A 14% improvement in acceleration for free is a really big deal. In case anyone doesn't know this mod idea came from Wester's Garage. He saw 11 rwhp on a stock 2008 GXP. I have been running it for over a month.

[spiky3480]

Dave...I have an auto. with your IC...can this adjustment be made? I live in NY.

[JustMike]

Yep I can tell you that I see the same thing with this mod on my daily driver. Used to have a shift pattern that would leave me in 3rd doing 60 ... (10 above the posted limit on most of the roads that I drive). After the mod the same shift pattern leaves me sitting at 70 ...

[lil goat]

It will work on an auto, at least in theory, but not on a car with a BSR tune. This is the same mod I posted, a couple of weeks ago. Dave has been kind enough to validate it. Hahn says if you have the BSR don't do it.

[DEJON-Dave]

Originally Posted by spiky3480 Dave...I have an auto. with your IC...can this adjustment be made? I live in NY.

I don't know why not. It is easily reverse able if problems occur
Dave

[Drivetime]

Originally Posted by lil goat It will work on an auto, at least in theory, but not on a car with a BSR tune. This is the same mod I posted, a couple of weeks ago. Dave has been kind enough to validate it. Hahn says if you have the BSR don't do it.

A quote from Bill Hahn on an earlier thread about the mod.:

"For those of you who are already Hahn/BSR PPC Tuner-equipped, this mod may be risky, in that it could elevate boost levels to an unsafe level. The BSR tune already increases boost pressure via the stock boost control solenoid, and optimizes engine parameters for safety accordingly. As such, this wastegate-adjustment method of boost increase is essentially redundant, and potentially damaging, for PPC-equipped cars."

The BSR tune already hits 23 lbs. If I did not have the BSR tune, I would do this one in a second.

[kwtoxman]

Originally Posted by Drivetime The BSR tune already hits 23 lbs. If I did not have the BSR tune, I would do this one in a second.

Why? The other thread on this topic showed the ECM was backing off the gains after a little while.

kw.........

[Drivetime]

Originally Posted by kwtoxman Why? The other thread on this topic showed the ECM was backing off the gains after a little while. kw.........

Which gains? From the BSR tune or the wastegate rod mod? I have not seen any backing down from the tune. I don't know about the wastegate mod. But I have not read about any backing down from it either.

[DEJON-Dave]

Originally Posted by kwtoxman Why? The other thread on this topic showed the ECM was backing off the gains after a little while. kw.........

I put at least 30 runs on my car with this combo of tune, parts and mod and the power does not back off.

[DEJON-Dave]

Originally Posted by Drivetime A quote from Bill Hahn on an earlier thread about the mod.: "For those of you who are already Hahn/BSR PPC Tuner-equipped, this mod may be risky, in that it could elevate boost levels to an unsafe level. The BSR tune already increases boost pressure via the stock boost control solenoid, and optimizes engine parameters for safety accordingly. As such, this wastegate-adjustment method of boost increase is essentially redundant, and potentially damaging, for PPC-equipped cars." The BSR tune already hits 23 lbs. If I did not have the BSR tune, I would do this one in a second.

I'm very curious, can you do a 3rd gear pull from 2000 to redline? what rpm do you get 23 psi at, and does it hold or drop down to 16 or so then build back up to what max around 5500
Dave

[lil goat]

I have not had the mod back off, boost comes on a lot sooner and is higher. It smooths out a liitle after it learns. I have the Dejon Intercooler same as Dave and my levels have not dropped off, we saw on the dyno almost 17 hp from the Dejon intercooler, on cars with the same tune and exhaust, both had the mod. I think the ECM may back off boost levels a little due to heat if you have a stock intercooler. It is still worth doing as boost is still coming on much sooner.

[shabby]

This is definetly a great free mod, best one so far thats for sure.
I noticed im my 3rd gear log that i shaved off a full second from 2000-6000rpm... full second. If only the track wasnt covered in snow

[HotScott]

The computer does back off the boost after a few hundred miles, but the quick boost up still stays. I reset my computer and the 2psi gain comes back. I have no other computer mods, and just IC pipes upgrade. So far its still staying up since I reset, but I think boost spike will go away again. Still worth it tho, as stated above, the boost comes in much quicker.

[mena661]

Anyone have the ED mod with this? Thanks.